SEC EDGAR filings, ownership reports, and insider transactions for NORTHWESTERN CORP.
Recent SEC filings for NORTHWESTERN CORP including SC 13G/A, 15-12G, 8-K and more.
| Form type | Document | Filing | Description | Filing date | Reporting date | File number(s) |
|---|---|---|---|---|---|---|
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SCHEDULE 13G/A | 13 Feb 2024 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 22 Jan 2024 | 005-36015 | ||
| 15-12G | Open 15-12G document | View SEC filing for 15-12G | 15-12G | 07 Dec 2023 | 001-10499 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 06 Dec 2023 | 06 Dec 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 05 Dec 2023 | 29 Nov 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 13 Nov 2023 | 12 Nov 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 27 Oct 2023 | 26 Oct 2023 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 27 Oct 2023 | 30 Sep 2023 | 001-10499 |
| POSASR | Open POSASR document | View SEC filing for POSASR | POSASR | 02 Oct 2023 | 333-253047 | |
| POSASR | Open POSASR document | View SEC filing for POSASR | POSASR | 02 Oct 2023 | 333-257950 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-175813 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-149388 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-124624 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-122428 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 033-56401 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-11843 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-18991 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-80819 | |
| S-8 POS | Open S-8 POS document | View SEC filing for S-8 POS | S-8 POS | 02 Oct 2023 | 333-80817 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 02 Oct 2023 | 02 Oct 2023 | 001-10499 |
| 25-NSE | Open 25-NSE document | View SEC filing for 25-NSE | 29 Sep 2023 | 001-10499 | ||
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 13 Sep 2023 | 13 Sep 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 25 Jul 2023 | 24 Jul 2023 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 25 Jul 2023 | 30 Jun 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 06 Jul 2023 | 29 Jun 2023 | 001-10499 |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 16 Jun 2023 | 16 Jun 2023 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 15 Jun 2023 | 15 Jun 2023 | 001-10499 |
| 424B3 | Open 424B3 document | View SEC filing for 424B3 | SUPPLEMENT TO PROSPECTUS SUPPLEMENT | 15 Jun 2023 | 333-253047 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 09 Jun 2023 | 05 Jun 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 08 Jun 2023 | 08 Jun 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 07 Jun 2023 | 01 Jun 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 19 May 2023 | 19 May 2023 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 17 May 2023 | 16 May 2023 | |
| 144 | Open 144 document | View SEC filing for 144 | 16 May 2023 | 001-10499 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 11 May 2023 | 09 May 2023 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 05 May 2023 | 01 May 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 03 May 2023 | 28 Apr 2023 | 001-10499 |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 01 May 2023 | 28 Apr 2023 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 28 Apr 2023 | 27 Apr 2023 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 28 Apr 2023 | 31 Mar 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 05 Apr 2023 | 03 Apr 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 05 Apr 2023 | 30 Mar 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 15 Mar 2023 | 15 Mar 2023 | 001-10499 |
| ARS | Open ARS document | View SEC filing for ARS | ARS | 14 Mar 2023 | 14 Mar 2023 | 001-10499 |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A | 14 Mar 2023 | 001-10499 | |
| DEF 14A | Open DEF 14A document | Open XBRL data | View SEC filing for DEF 14A | DEF 14A | 14 Mar 2023 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2023 | 07 Mar 2023 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 08 Mar 2023 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 03 Mar 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2023 | 06 Mar 2023 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 27 Feb 2023 | 27 Feb 2023 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 23 Feb 2023 | 23 Feb 2023 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 23 Feb 2023 | 17 Feb 2023 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 17 Feb 2023 | 16 Feb 2023 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | 10-K | 17 Feb 2023 | 31 Dec 2022 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 14 Feb 2023 | 005-36015 | ||
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SCHEDULE 13G/A | 09 Feb 2023 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SC 13G/A | 08 Feb 2023 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2023 | 02 Feb 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2023 | 02 Feb 2023 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 23 Jan 2023 | 005-36015 | ||
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 17 Jan 2023 | 16 Jan 2023 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2023 | 06 Jan 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2023 | 06 Jan 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2023 | 06 Jan 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2023 | 06 Jan 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2023 | 06 Jan 2023 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2023 | 06 Jan 2023 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 05 Jan 2023 | 21 Dec 2022 | 001-10499 |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 03 Jan 2023 | 03 Jan 2023 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 03 Jan 2023 | 03 Jan 2023 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 19 Dec 2022 | 13 Dec 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Dec 2022 | 13 Dec 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 07 Dec 2022 | 07 Dec 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 01 Dec 2022 | 28 Nov 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 14 Nov 2022 | 14 Nov 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 14 Nov 2022 | 14 Nov 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2022 | 03 Nov 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 03 Nov 2022 | 28 Oct 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Oct 2022 | 28 Oct 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 25 Oct 2022 | 24 Oct 2022 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 25 Oct 2022 | 30 Sep 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 22 Sep 2022 | 21 Sep 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 22 Sep 2022 | 22 Sep 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Sep 2022 | 15 Sep 2022 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 07 Sep 2022 | 31 Aug 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 31 Aug 2022 | 31 Aug 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Aug 2022 | 09 Aug 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 09 Aug 2022 | 08 Aug 2022 | 001-10499 |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 04 Aug 2022 | 28 Jul 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 01 Aug 2022 | 28 Jul 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 28 Jul 2022 | 27 Jul 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 28 Jul 2022 | 27 Jul 2022 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 28 Jul 2022 | 30 Jun 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K PARTIAL FORWARD SETTLEMENT JUNE 2022 | 28 Jun 2022 | 24 Jun 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Jun 2022 | 15 Jun 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 23 May 2022 | 18 May 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 17 May 2022 | 17 May 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 05 May 2022 | 29 Apr 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 29 Apr 2022 | 28 Apr 2022 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 29 Apr 2022 | 31 Mar 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 17 Mar 2022 | 17 Mar 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2022 | 07 Mar 2022 | |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A 2022 ANNUAL MTG NOTICE | 07 Mar 2022 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A | 07 Mar 2022 | 29 Apr 2022 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 03 Mar 2022 | 03 Mar 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2022 | 28 Feb 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 02 Mar 2022 | 02 Mar 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2022 | 25 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2022 | 24 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 23 Feb 2022 | 23 Feb 2022 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 16 Feb 2022 | 10 Feb 2022 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 Feb 2022 | 15 Feb 2022 | |
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | 14 Feb 2022 | 005-36015 | ||
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 14 Feb 2022 | 10 Feb 2022 | 001-10499 |
| S-8 | Open S-8 document | View SEC filing for S-8 | S-8 | 14 Feb 2022 | 333-262705 | |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | 10-K | 11 Feb 2022 | 31 Dec 2021 | 001-10499 |
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | 10 Feb 2022 | 005-36015 | ||
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SCHEDULE 13G/A | 09 Feb 2022 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SC 13G/A | 04 Feb 2022 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2022 | 01 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2022 | 01 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2022 | 01 Feb 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2022 | 01 Feb 2022 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 27 Jan 2022 | 005-36015 | ||
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | 25 Jan 2022 | 005-36015 | ||
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 10 Jan 2022 | |||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2022 | 03 Jan 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2022 | 03 Jan 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2022 | 03 Jan 2022 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2022 | 03 Jan 2022 | |
| CORRESP | Open CORRESP document | View SEC filing for CORRESP | 30 Dec 2021 | |||
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 20 Dec 2021 | 14 Dec 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Dec 2021 | 15 Dec 2021 | |
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 15 Dec 2021 | |||
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 08 Dec 2021 | 08 Dec 2021 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | FILING NORTHWESTERN CORP | 07 Dec 2021 | 005-36015 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 19 Nov 2021 | 15 Nov 2021 | 001-10499 |
| 424B2 | Open 424B2 document | View SEC filing for 424B2 | 424B5 | 18 Nov 2021 | 333-253047 | |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 15 Nov 2021 | 333-253047 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 08 Nov 2021 | 08 Nov 2021 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 25 Oct 2021 | 24 Oct 2021 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 25 Oct 2021 | 30 Sep 2021 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 22 Sep 2021 | 22 Sep 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Sep 2021 | 15 Sep 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 09 Sep 2021 | 09 Sep 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Aug 2021 | 23 Aug 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Aug 2021 | 05 Aug 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 28 Jul 2021 | 27 Jul 2021 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 28 Jul 2021 | 30 Jun 2021 | 001-10499 |
| S-3ASR | Open S-3ASR document | View SEC filing for S-3ASR | S-3ASR | 16 Jul 2021 | 333-257950 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 22 Jun 2021 | 22 Jun 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 16 Jun 2021 | 16 Jun 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 14 May 2021 | 14 May 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 13 May 2021 | 13 May 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 29 Apr 2021 | 29 Apr 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 28 Apr 2021 | 28 Apr 2021 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K ANNUAL MEETING VOTING RESULTS 2021 | 27 Apr 2021 | 22 Apr 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Apr 2021 | 26 Apr 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | FORM 8-K | 23 Apr 2021 | 23 Apr 2021 | 001-10499 |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 23 Apr 2021 | 333-253047 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 22 Apr 2021 | 21 Apr 2021 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 22 Apr 2021 | 31 Mar 2021 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 01 Apr 2021 | 26 Mar 2021 | 001-10499 |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 22 Mar 2021 | 333-253047 | |
| FWP | Open FWP document | View SEC filing for FWP | FWP | 19 Mar 2021 | 333-253047 | |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 19 Mar 2021 | 333-253047 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 15 Mar 2021 | 15 Mar 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Mar 2021 | 05 Mar 2021 | |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A | 05 Mar 2021 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A | 05 Mar 2021 | 22 Apr 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2021 | 01 Mar 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2021 | 01 Mar 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2021 | 01 Mar 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 01 Mar 2021 | 01 Mar 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2021 | 24 Feb 2021 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 24 Feb 2021 | 15 Feb 2021 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 24 Feb 2021 | 15 Feb 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 17 Feb 2021 | 11 Feb 2021 | 001-10499 |
| S-3ASR | Open S-3ASR document | View SEC filing for S-3ASR | S-3ASR 2021 | 12 Feb 2021 | 333-253047 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 12 Feb 2021 | 11 Feb 2021 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | 10-K | 12 Feb 2021 | 31 Dec 2020 | 001-10499 |
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | SC 13G | 11 Feb 2021 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SCHEDULE 13G/A | 10 Feb 2021 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SCHEDULE 13G/A | 10 Feb 2021 | 005-36015 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 10 Feb 2021 | 05 Feb 2021 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2021 | 01 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2021 | 01 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2021 | 01 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2021 | 01 Feb 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2021 | 01 Feb 2021 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 26 Jan 2021 | 005-36015 | ||
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | FILING NORTHWESTERN CORP | 15 Jan 2021 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2021 | 04 Jan 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2021 | 04 Jan 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2021 | 04 Jan 2021 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2021 | 04 Jan 2021 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 30 Dec 2020 | 22 Dec 2020 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Dec 2020 | 15 Dec 2020 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 07 Dec 2020 | 07 Dec 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 01 Dec 2020 | 01 Dec 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 09 Nov 2020 | 09 Nov 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K COLSTRIP TERMINATION | 30 Oct 2020 | 29 Oct 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 27 Oct 2020 | 27 Oct 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K EARNINGS RELEASE Q3 2020 | 22 Oct 2020 | 21 Oct 2020 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 22 Oct 2020 | 30 Sep 2020 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Oct 2020 | 15 Oct 2020 | |
| CERT | Open CERT document | View SEC filing for CERT | 30 Sep 2020 | 001-31229-01 | ||
| 25 | Open 25 document | View SEC filing for 25 | 25 | 30 Sep 2020 | 001-31229-01 | |
| 8-A12B | Open 8-A12B document | View SEC filing for 8-A12B | 8-A12B | 30 Sep 2020 | 001-10499 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 24 Sep 2020 | 24 Sep 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 18 Sep 2020 | 18 Sep 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 10 Sep 2020 | 10 Sep 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 04 Sep 2020 | 02 Sep 2020 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Sep 2020 | 03 Sep 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Sep 2020 | 02 Sep 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 18 Aug 2020 | 17 Aug 2020 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 12 Aug 2020 | 12 Aug 2020 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Aug 2020 | 06 Aug 2020 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 29 Jul 2020 | 28 Jul 2020 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 29 Jul 2020 | 30 Jun 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 16 Jun 2020 | 16 Jun 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 20 May 2020 | 15 May 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 14 May 2020 | 14 May 2020 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 08 May 2020 | 06 May 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 May 2020 | 06 May 2020 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 29 Apr 2020 | 23 Apr 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 23 Apr 2020 | 22 Apr 2020 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 23 Apr 2020 | 31 Mar 2020 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 07 Apr 2020 | 06 Apr 2020 | 001-10499 |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A 2020 VIRTUAL MEETING NOTICE | 31 Mar 2020 | 001-10499 | |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A 2020 ANNUAL MTG NOTICE | 06 Mar 2020 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A 2020 PROXY STATEMENT | 06 Mar 2020 | 23 Apr 2020 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Mar 2020 | 06 Mar 2020 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 03 Mar 2020 | 03 Mar 2020 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2020 | 27 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2020 | 26 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2020 | 21 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2020 | 24 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 19 Feb 2020 | 18 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 19 Feb 2020 | 18 Feb 2020 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 13 Feb 2020 | 13 Feb 2020 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | 10-K | 13 Feb 2020 | 31 Dec 2019 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SCHEDULE 13G/A | 12 Feb 2020 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | SC 13G/A | 11 Feb 2020 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2020 | 03 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2020 | 03 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2020 | 03 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2020 | 03 Feb 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2020 | 03 Feb 2020 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 04 Feb 2020 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2020 | 02 Jan 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2020 | 02 Jan 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2020 | 02 Jan 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2020 | 02 Jan 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2020 | 02 Jan 2020 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2020 | 02 Jan 2020 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 23 Dec 2019 | 23 Dec 2019 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 18 Dec 2019 | 17 Dec 2019 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 13 Dec 2019 | 13 Dec 2019 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 10 Dec 2019 | 10 Dec 2019 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Dec 2019 | 06 Dec 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Dec 2019 | 29 Nov 2019 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 03 Dec 2019 | 03 Dec 2019 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 08 Nov 2019 | 08 Nov 2019 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Nov 2019 | 06 Nov 2019 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 01 Nov 2019 | 01 Nov 2019 | 001-10499 |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 31 Oct 2019 | 31 Oct 2019 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 30 Oct 2019 | 30 Oct 2019 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 30 Oct 2019 | 30 Sep 2019 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 02 Oct 2019 | 02 Oct 2019 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 20 Sep 2019 | 20 Sep 2019 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 04 Sep 2019 | 04 Sep 2019 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 08 Aug 2019 | 06 Aug 2019 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 ROWE 2019 AUG 05 | 05 Aug 2019 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Aug 2019 | 01 Aug 2019 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 SCHROEPPEL JULY 2019 | 31 Jul 2019 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 29 Jul 2019 | 26 Jul 2019 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 GRAHAME JULY 2019 | 25 Jul 2019 | 001-10499 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K | 24 Jul 2019 | 24 Jul 2019 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 24 Jul 2019 | 30 Jun 2019 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K MT FIRST MORTGAGE BONDS 2019 | 02 Jul 2019 | 26 Jun 2019 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 13 Jun 2019 | 13 Jun 2019 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 ROWE JUNE 2019 | 13 Jun 2019 | 001-10499 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2019 AGA FINANCIAL FORUM | 21 May 2019 | 21 May 2019 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2019 ANNUAL MEETING VOTING RESULTS | 30 Apr 2019 | 24 Apr 2019 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Apr 2019 | 23 Apr 2019 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 24 Apr 2019 | 31 Mar 2019 | 001-10499 |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A ADDITIONAL MATERIALS 2019 | 05 Apr 2019 | 001-10499 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K WEST COAST UTILITIES 2019 | 20 Mar 2019 | 20 Mar 2019 | 001-10499 |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A 2019 ANNUAL MEETING NOTICE | 07 Mar 2019 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A 2019 PROXY STATEMENT | 07 Mar 2019 | 24 Apr 2019 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K NEW YORK BOSTON PRESENTATION | 05 Mar 2019 | 05 Mar 2019 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2019 | 27 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Feb 2019 | 25 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Feb 2019 | 25 Feb 2019 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 HORSFALL FEB 22 2019 | 22 Feb 2019 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 19 Feb 2019 | 19 Feb 2019 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2019 LTIP AWARDS | 15 Feb 2019 | 11 Feb 2019 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 12 Feb 2019 | 11 Feb 2019 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | FORM 10-K 2018 | 12 Feb 2019 | 31 Dec 2018 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 11 Feb 2019 | 005-36015 | ||
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | SC 13G | 11 Feb 2019 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2019 | 01 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2019 | 01 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2019 | 01 Feb 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2019 | 01 Feb 2019 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 31 Jan 2019 | 005-36015 | ||
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | NONE | 07 Jan 2019 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2019 | 02 Jan 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2019 | 02 Jan 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2019 | 02 Jan 2019 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2019 | 02 Jan 2019 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2019 ANNUAL INCENTIVE AND 2018 ERRP GRANTS | 19 Dec 2018 | 13 Dec 2018 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2018 WELLS FARGO | 04 Dec 2018 | 04 Dec 2018 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Nov 2018 | 16 Nov 2018 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 GRAHAME NOV 2018 | 15 Nov 2018 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 13 Nov 2018 | 08 Nov 2018 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 13 Nov 2018 | 005-36015 | ||
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 09 Nov 2018 | 09 Nov 2018 | 001-10499 |
| 144 | Open 144 document | View SEC filing for 144 | 144 HORSFALL NOV 6 2018 | 06 Nov 2018 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 30 Oct 2018 | 29 Oct 2018 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Oct 2018 | 24 Oct 2018 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q SEPTEMBER 30, 2018 | 24 Oct 2018 | 30 Sep 2018 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K BAML TX POWER CONFERENCE | 27 Sep 2018 | 27 Sep 2018 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K FALL INVESTOR MEETINGS 2018 | 12 Sep 2018 | 12 Sep 2018 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K BARCLAYS POWER CONF 2018 | 04 Sep 2018 | 04 Sep 2018 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Jul 2018 | 27 Jul 2018 | |
| 4/A | Open 4/A document | View SEC filing for 4/A | FORM 4/A | 25 Jul 2018 | 24 Jul 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Jul 2018 | 24 Jul 2018 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K OHIO PRESENTATION 2018 | 23 Jul 2018 | 23 Jul 2018 | 001-10499 |
| S-3ASR | Open S-3ASR document | View SEC filing for S-3ASR | S-3ASR DRIP REG STMT 2018 | 20 Jul 2018 | 333-226253 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K EARNINGS RELEASE Q2 2018 | 20 Jul 2018 | 19 Jul 2018 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q 6.30.18 | 20 Jul 2018 | 30 Jun 2018 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2018 AGA FINANCIAL CONFERENCE | 18 May 2018 | 18 May 2018 | 001-10499 |
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 15 May 2018 | |||
| CORRESP | Open CORRESP document | View SEC filing for CORRESP | 02 May 2018 | |||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2018 | 30 Apr 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2018 | 01 May 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2018 | 01 May 2018 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K ANNUAL MEETING VOTING RESULTS | 30 Apr 2018 | 25 Apr 2018 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K EARNINGS RELEASE Q1 2018 | 25 Apr 2018 | 24 Apr 2018 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q 3.31.18 | 25 Apr 2018 | 31 Mar 2018 | 001-10499 |
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 18 Apr 2018 | |||
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K WEST COAST UTILITIES 2018 | 21 Mar 2018 | 21 Mar 2018 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 Mar 2018 | 08 Mar 2018 | |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A 2018 ANNUAL MEETING NOTICE | 07 Mar 2018 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A 2018 PROXY STATEMENT | 07 Mar 2018 | 25 Apr 2018 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2018 | 02 Mar 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2018 | 28 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Feb 2018 | 27 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 26 Feb 2018 | 22 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Feb 2018 | 15 Feb 2018 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2018 LTIP AWARDS | 16 Feb 2018 | 12 Feb 2018 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 15 Feb 2018 | 15 Feb 2018 | 001-10499 |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 15 Feb 2018 | 333-223019 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K DRAPER RESIGNATION | 15 Feb 2018 | 12 Feb 2018 | 001-10499 |
| S-3ASR | Open S-3ASR document | View SEC filing for S-3ASR | S-3ASR 2018 | 13 Feb 2018 | 333-223019 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K Q4 2017 EARNINGS | 13 Feb 2018 | 12 Feb 2018 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | FORM 10-K 2017 | 13 Feb 2018 | 31 Dec 2017 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 09 Feb 2018 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Feb 2018 | 02 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Feb 2018 | 02 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Feb 2018 | 02 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Feb 2018 | 02 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Feb 2018 | 02 Feb 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Feb 2018 | 02 Feb 2018 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 19 Jan 2018 | 005-36015 | ||
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | NONE | 10 Jan 2018 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Jan 2018 | 03 Jan 2018 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Jan 2018 | 03 Jan 2018 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2017 DEC NY PRESENTATION | 04 Dec 2017 | 04 Dec 2017 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Dec 2017 | 01 Dec 2017 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K MONTANA FMB NOV 2017 | 08 Nov 2017 | 06 Nov 2017 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Nov 2017 | 06 Nov 2017 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2017 EEI FINANCIAL | 03 Nov 2017 | 03 Nov 2017 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Nov 2017 | 01 Nov 2017 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K EARNINGS RELEASE Q3 2017 | 02 Nov 2017 | 02 Nov 2017 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q SEPTEMBER 30, 2017 | 02 Nov 2017 | 30 Sep 2017 | 001-10499 |
| 144 | Open 144 document | View SEC filing for 144 | ROWE FORM 144 OCTOBER 16 2017 | 16 Oct 2017 | 001-10499 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 06 Sep 2017 | 06 Sep 2017 | 001-10499 |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 06 Sep 2017 | 333-202126 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Sep 2017 | 01 Sep 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 25 Aug 2017 | 24 Aug 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2017 | 01 Aug 2017 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K 2017 Q2 EARNINGS | 26 Jul 2017 | 25 Jul 2017 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q JUNE 30, 2017 | 26 Jul 2017 | 30 Jun 2017 | 001-10499 |
| 4/A | Open 4/A document | View SEC filing for 4/A | FORM 4/A | 08 Jun 2017 | 05 Jun 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jun 2017 | 05 Jun 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 30 May 2017 | 26 May 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 30 May 2017 | 26 May 2017 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2017 MIDWEST AND AGA FINANCIAL FORUM | 17 May 2017 | 17 May 2017 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 15 May 2017 | 15 May 2017 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 ROWE MAY 11 2017 | 11 May 2017 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 May 2017 | 03 May 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 May 2017 | 01 May 2017 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2017 ANNUAL MEETING VOTING RESULTS | 02 May 2017 | 27 Apr 2017 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2017 | 01 May 2017 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 28 Apr 2017 | 28 Apr 2017 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 28 Apr 2017 | 28 Apr 2017 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K Q1 2017 EARNINGS | 27 Apr 2017 | 27 Apr 2017 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q MARCH 31, 2017 | 27 Apr 2017 | 31 Mar 2017 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K WEST COAST UTILITIES 2017 | 22 Mar 2017 | 22 Mar 2017 | 001-10499 |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A 2017 ANNUAL MEETING NOTICE | 16 Mar 2017 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A 2017 PROXY STATEMENT | 16 Mar 2017 | 16 Mar 2017 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 10 Mar 2017 | 10 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 08 Mar 2017 | 08 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2017 | 06 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2017 | 07 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Mar 2017 | 03 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2017 | 01 Mar 2017 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 02 Mar 2017 | 005-36015 | ||
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2017 UBS UTILITIES | 28 Feb 2017 | 28 Feb 2017 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K BRADLEY RESIGNATION | 27 Feb 2017 | 22 Feb 2017 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2017 LTIP AWARDS | 23 Feb 2017 | 16 Feb 2017 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K Q4 2016 EARNINGS | 17 Feb 2017 | 16 Feb 2017 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | FORM 10-K 12.31.16 | 17 Feb 2017 | 31 Dec 2016 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 13 Feb 2017 | 005-36015 | ||
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 10 Feb 2017 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2017 | 02 Feb 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2017 | 02 Feb 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2017 | 02 Feb 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2017 | 02 Feb 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2017 | 02 Feb 2017 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 17 Jan 2017 | 005-36015 | ||
| 4/A | Open 4/A document | View SEC filing for 4/A | FORM 4/A | 10 Jan 2017 | 03 Jan 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 10 Jan 2017 | 09 Jan 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2017 | 03 Jan 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2017 | 03 Jan 2017 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Jan 2017 | 03 Jan 2017 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K THIRD AMENDED CREDIT AGREEMENT | 16 Dec 2016 | 12 Dec 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 ERRP AND 2017 ANNUAL INCENTIVE PLAN | 13 Dec 2016 | 07 Dec 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 12 12 EAST COAST INVESTOR MEETINGS | 12 Dec 2016 | 12 Dec 2016 | 001-10499 |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 09 Dec 2016 | 09 Dec 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K TONY CLARK DIRECTOR | 08 Dec 2016 | 06 Dec 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 28 Nov 2016 | 28 Nov 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 21 Nov 2016 | 21 Nov 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 EEI FINANCIAL CONFERENCE | 04 Nov 2016 | 04 Nov 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Nov 2016 | 01 Nov 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Nov 2016 | 01 Nov 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Nov 2016 | 01 Nov 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K KEY EMPLOYEE SEVERANCE PLAN 2016 | 25 Oct 2016 | 19 Oct 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 WEST COAST PRESENTATION | 24 Oct 2016 | 24 Oct 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K Q3 2016 EARNINGS | 20 Oct 2016 | 20 Oct 2016 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q SEPTEMBER 30, 2016 | 20 Oct 2016 | 30 Sep 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 09 30 SD FMB | 07 Oct 2016 | 30 Sep 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 20 Sep 2016 | 19 Sep 2016 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 ROWE SEPT 19 2016 | 19 Sep 2016 | 001-10499 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 09 08 NY INVESTORS | 08 Sep 2016 | 08 Sep 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 POLLUTION CONTROL BONDS | 16 Aug 2016 | 11 Aug 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2016 | 02 Aug 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2016 | 01 Aug 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2016 | 01 Aug 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2016 | 01 Aug 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 29 Jul 2016 | 27 Jul 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 Q2 EARNINGS RELEASE | 22 Jul 2016 | 22 Jul 2016 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q JUNE 30, 2016 | 22 Jul 2016 | 30 Jun 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K SD FMB | 22 Jun 2016 | 15 Jun 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 10 Jun 2016 | 09 Jun 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 08 Jun 2016 | 07 Jun 2016 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 ROWE JUNE 6 2016 | 06 Jun 2016 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 20 May 2016 | 19 May 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 AMENDMENT OF ARTICLES AND BYLAWS | 18 May 2016 | 12 May 2016 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K 2016 AGA FINANCIAL FORUM | 13 May 2016 | 13 May 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 May 2016 | 02 May 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 May 2016 | 02 May 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 May 2016 | 02 May 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 May 2016 | 02 May 2016 | |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K SD INVEST SOC PRESENTATION | 28 Apr 2016 | 28 Apr 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 27 Apr 2016 | 26 Apr 2016 | |
| 144 | Open 144 document | View SEC filing for 144 | 144 HORSFALL APR 26 2016 | 26 Apr 2016 | 001-10499 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 ANNUAL MEETING RESULTS | 26 Apr 2016 | 20 Apr 2016 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K 2016 04 25 NY AND MIDW MTGS | 25 Apr 2016 | 25 Apr 2016 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K EARNINGS RELEASE Q1 2016 | 20 Apr 2016 | 20 Apr 2016 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q 3.31.16 | 20 Apr 2016 | 31 Mar 2016 | 001-10499 |
| 8-K | Open 8-K document | Open XBRL data | View SEC filing for 8-K | 8-K 2016 WILLIAMS WEST COAST UTILITY | 16 Mar 2016 | 16 Mar 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 14 Mar 2016 | 14 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 14 Mar 2016 | 14 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 11 Mar 2016 | 10 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Mar 2016 | 04 Mar 2016 | |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A 2016 ANNUAL MTG NOTICE | 07 Mar 2016 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A 2016 PROXY STATEMENT | 07 Mar 2016 | 20 Apr 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Mar 2016 | 01 Mar 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 UBS UTILITIES CONFERENCE | 01 Mar 2016 | 01 Mar 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Feb 2016 | 16 Feb 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 16 Feb 2016 | 16 Feb 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2016 ANNUAL AND LONG-TERM INCENTIVE | 16 Feb 2016 | 10 Feb 2016 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 16 Feb 2016 | 005-36015 | ||
| PRE 14A | Open PRE 14A document | View SEC filing for PRE 14A | DEF 14A PRELIMINARY PROXY STATEMENT | 12 Feb 2016 | 20 Apr 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 FINANCIAL RESULTS | 11 Feb 2016 | 11 Feb 2016 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 11 Feb 2016 | 005-36015 | ||
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | 10-K | 11 Feb 2016 | 31 Dec 2015 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | NWE AS OF 12/31/2015 | 09 Feb 2016 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2016 | 02 Feb 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2016 | 02 Feb 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2016 | 02 Feb 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2016 | 02 Feb 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Feb 2016 | 02 Feb 2016 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 29 Jan 2016 | 29 Jan 2016 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K PEOPLES RETIREMENT | 20 Jan 2016 | 14 Jan 2016 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 11 Jan 2016 | 07 Jan 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 11 Jan 2016 | 07 Jan 2016 | |
| NO ACT | Open NO ACT document | View SEC filing for NO ACT | AUTO-GENERATED PAPER DOCUMENT | 08 Jan 2016 | 11 Dec 2015 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 08 Jan 2016 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2016 | 04 Jan 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2016 | 04 Jan 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 06 Jan 2016 | 04 Jan 2016 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Dec 2015 | 01 Dec 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 50TH EEI FINANCIAL CONFERENCE PRESENTATION | 09 Nov 2015 | 09 Nov 2015 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Nov 2015 | 01 Nov 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Nov 2015 | 01 Nov 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Nov 2015 | 01 Nov 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Nov 2015 | 01 Nov 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Nov 2015 | 01 Nov 2015 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 26 Oct 2015 | 26 Oct 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K LAIL APPOINTMENT | 22 Oct 2015 | 21 Oct 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 3RD Q FINANCIAL RESULTS | 22 Oct 2015 | 21 Oct 2015 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q SEPTEMBER 30, 2015 | 22 Oct 2015 | 30 Sep 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K KLIEWER DEPARTURE | 16 Oct 2015 | 13 Oct 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K SD FMBS AND UA | 05 Oct 2015 | 29 Sep 2015 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Oct 2015 | 01 Oct 2015 | |
| 424B2 | Open 424B2 document | View SEC filing for 424B2 | 424B2 | 30 Sep 2015 | 333-202126 | |
| 424B2 | Open 424B2 document | View SEC filing for 424B2 | 424B2 | 29 Sep 2015 | 333-202126 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K SD RATE CASE AND BEETHOVEN | 25 Sep 2015 | 25 Sep 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 NORTHEAST PRESENTATION | 15 Sep 2015 | 15 Sep 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K LRAM INFORMATION | 11 Sep 2015 | 08 Sep 2015 | 001-10499 |
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 08 Sep 2015 | |||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Sep 2015 | 01 Sep 2015 | |
| CORRESP | Open CORRESP document | View SEC filing for CORRESP | 28 Aug 2015 | |||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 20 Aug 2015 | 18 Aug 2015 | |
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 14 Aug 2015 | |||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 11 Aug 2015 | 07 Aug 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Aug 2015 | 04 Aug 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2015 | 03 Aug 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2015 | 03 Aug 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2015 | 03 Aug 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2015 | 03 Aug 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2015 | 03 Aug 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 UBS TORONTO PRESENTATION | 28 Jul 2015 | 28 Jul 2015 | 001-10499 |
| S-3ASR | Open S-3ASR document | View SEC filing for S-3ASR | S-3ASR | 24 Jul 2015 | 333-205834 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K BEETHOVEN ACQUISITION | 23 Jul 2015 | 22 Jul 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 2ND Q FINANCIAL RESULTS | 23 Jul 2015 | 23 Jul 2015 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q JUNE 30, 2015 | 23 Jul 2015 | 30 Jun 2015 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 10 Jul 2015 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2015 | 01 Jul 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2015 | 01 Jul 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2015 | 01 Jul 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2015 | 01 Jul 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2015 | 01 Jul 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K MT FIRST MORTGAGE BONDS 2015 | 29 Jun 2015 | 23 Jun 2015 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Jun 2015 | 01 Jun 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 AGA FINANCIAL FORUM | 18 May 2015 | 18 May 2015 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 12 May 2015 | 12 May 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 11 May 2015 | 11 May 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 May 2015 | 05 May 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 May 2015 | 01 May 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 May 2015 | 30 Apr 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 May 2015 | 30 Apr 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 May 2015 | 30 Apr 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 May 2015 | 30 Apr 2015 | |
| 3 | Open 3 document | View SEC filing for 3 | FORM 3 | 01 May 2015 | 01 May 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 ANNUAL MEETING VOTING RESULTS | 29 Apr 2015 | 23 Apr 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K NY PRESENTATION 04 2015 | 27 Apr 2015 | 27 Apr 2015 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K Q1 2015 EARNINGS | 23 Apr 2015 | 23 Apr 2015 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q 3.31.15 | 23 Apr 2015 | 31 Mar 2015 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2015 | 01 Apr 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 17 Mar 2015 | 17 Mar 2015 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2015 | 06 Mar 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 09 Mar 2015 | 06 Mar 2015 | |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | ANNUAL MEETING NOTICE | 06 Mar 2015 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A | 06 Mar 2015 | 31 Dec 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2015 | 02 Mar 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2015 | 02 Mar 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2015 | 02 Mar 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2015 | 02 Mar 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2015 | 02 Mar 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Mar 2015 | 02 Mar 2015 | |
| ARS | Open ARS document | View SEC filing for ARS | AUTO-GENERATED PAPER DOCUMENT | 27 Feb 2015 | 31 Dec 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2015 | 23 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2015 | 23 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2015 | 23 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2015 | 23 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2015 | 23 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2015 | 23 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 24 Feb 2015 | 23 Feb 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K 2015 LTIP GRANTS | 18 Feb 2015 | 11 Feb 2015 | 001-10499 |
| S-3ASR | Open S-3ASR document | View SEC filing for S-3ASR | S-3ASR | 17 Feb 2015 | 333-202126 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | NORTHWESTERN AMENDEMENT | 17 Feb 2015 | 005-36015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K Q4 2014 EARNINGS | 12 Feb 2015 | 12 Feb 2015 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | 10-K NORTHWESTERN CORPORATION | 12 Feb 2015 | 31 Dec 2014 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | NWE AS OF 12/31/2014 | 11 Feb 2015 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 10 Feb 2015 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2015 | 02 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2015 | 02 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2015 | 02 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2015 | 02 Feb 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Feb 2015 | 02 Feb 2015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 15 Jan 2015 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2015 | 02 Jan 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2015 | 02 Jan 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2015 | 02 Jan 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2015 | 02 Jan 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2015 | 02 Jan 2015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 05 Jan 2015 | 05 Jan 2015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Dec 2014 | 19 Dec 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 22 Dec 2014 | 16 Dec 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 11 Dec 2014 | 10 Dec 2014 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 10 Dec 2014 | 005-36015 | ||
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | NORTHWESTERN INITIAL | 09 Dec 2014 | 005-36015 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 09 Dec 2014 | 09 Dec 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Dec 2014 | 01 Dec 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Dec 2014 | 01 Dec 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Nov 2014 | 18 Nov 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 14 Nov 2014 | 14 Nov 2014 | 001-10499 |
| 424B2 | Open 424B2 document | View SEC filing for 424B2 | 424B2 | 13 Nov 2014 | 333-179568 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 12 Nov 2014 | 05 Nov 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 10 Nov 2014 | 10 Nov 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | FORM 8-K | 10 Nov 2014 | 04 Nov 2014 | 001-10499 |
| 424B2 | Open 424B2 document | View SEC filing for 424B2 | 424B2 | 06 Nov 2014 | 333-179568 | |
| 424B2 | Open 424B2 document | View SEC filing for 424B2 | 424B2 | 05 Nov 2014 | 333-179568 | |
| FWP | Open FWP document | View SEC filing for FWP | FWP | 05 Nov 2014 | 333-179568 | |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 05 Nov 2014 | 333-179568 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2014 | 03 Nov 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2014 | 03 Nov 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2014 | 03 Nov 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2014 | 03 Nov 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2014 | 03 Nov 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2014 | 03 Nov 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 03 Nov 2014 | 03 Nov 2014 | 001-10499 |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | 424B5 | 03 Nov 2014 | 333-179568 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 30 Oct 2014 | 30 Oct 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 27 Oct 2014 | 27 Oct 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 23 Oct 2014 | 23 Oct 2014 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 23 Oct 2014 | 30 Sep 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 06 Oct 2014 | 01 Oct 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2014 | 01 Oct 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2014 | 01 Oct 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 10 Sep 2014 | 10 Sep 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Sep 2014 | 02 Sep 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Sep 2014 | 02 Sep 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2014 | 01 Aug 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2014 | 01 Aug 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2014 | 01 Aug 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2014 | 01 Aug 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2014 | 01 Aug 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Aug 2014 | 01 Aug 2014 | |
| S-8 | Open S-8 document | View SEC filing for S-8 | S-8 | 25 Jul 2014 | 333-197627 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Jul 2014 | 24 Jul 2014 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q JUNE 30, 2014 | 24 Jul 2014 | 30 Jun 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2014 | 30 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jun 2014 | 02 Jun 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jun 2014 | 02 Jun 2014 | |
| 4/A | Open 4/A document | View SEC filing for 4/A | FORM 4/A | 03 Jun 2014 | 01 Apr 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 16 May 2014 | 16 May 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 05 May 2014 | 05 May 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2014 | 01 May 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2014 | 01 May 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2014 | 01 May 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2014 | 01 May 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2014 | 01 May 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2014 | 01 May 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 29 Apr 2014 | 24 Apr 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Apr 2014 | 24 Apr 2014 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 24 Apr 2014 | 31 Mar 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 01 Apr 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 01 Apr 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 31 Mar 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 31 Mar 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 31 Mar 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 31 Mar 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 31 Mar 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2014 | 31 Mar 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 02 Apr 2014 | 02 Apr 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 20 Mar 2014 | 20 Mar 2014 | 001-10499 |
| ARS | Open ARS document | View SEC filing for ARS | AUTO-GENERATED PAPER DOCUMENT | 10 Mar 2014 | 31 Dec 2013 | 001-10499 |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A | 07 Mar 2014 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A | 07 Mar 2014 | 24 Apr 2014 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Mar 2014 | 28 Feb 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 04 Mar 2014 | 04 Mar 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Feb 2014 | 18 Feb 2014 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 19 Feb 2014 | 19 Feb 2014 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | FORM 10-K DECEMBER 31, 2013 | 19 Feb 2014 | 31 Dec 2013 | 001-10499 |
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | NORTHWESTERN CORP 13G | 12 Feb 2014 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 12 Feb 2014 | 005-36015 | ||
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | NWE AS OF 12/31/2013 | 10 Feb 2014 | 005-36015 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2014 | 03 Feb 2014 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 17 Jan 2014 | 005-36015 | ||
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 10 Jan 2014 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 31 Dec 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 31 Dec 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 31 Dec 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 31 Dec 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 31 Dec 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 31 Dec 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 02 Jan 2014 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jan 2014 | 02 Jan 2014 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 23 Dec 2013 | 19 Dec 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 16 Dec 2013 | 10 Dec 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 09 Dec 2013 | 09 Dec 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Dec 2013 | 02 Dec 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 18 Nov 2013 | 12 Nov 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 12 Nov 2013 | 11 Nov 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 08 Nov 2013 | 05 Nov 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 07 Nov 2013 | 06 Nov 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2013 | 01 Nov 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2013 | 01 Nov 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2013 | 01 Nov 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2013 | 01 Nov 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2013 | 01 Nov 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Nov 2013 | 01 Nov 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 24 Oct 2013 | 24 Oct 2013 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 24 Oct 2013 | 30 Sep 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2013 | 30 Sep 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2013 | 30 Sep 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2013 | 30 Sep 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2013 | 30 Sep 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2013 | 30 Sep 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2013 | 30 Sep 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2013 | 01 Oct 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 27 Sep 2013 | 26 Sep 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Sep 2013 | 03 Sep 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2013 | 01 Aug 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2013 | 01 Aug 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2013 | 01 Aug 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2013 | 01 Aug 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2013 | 01 Aug 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Aug 2013 | 01 Aug 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 30 Jul 2013 | 30 Jul 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 25 Jul 2013 | 25 Jul 2013 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 25 Jul 2013 | 30 Jun 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 16 Jul 2013 | 15 Jul 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2013 | 01 Jul 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2013 | 01 Jul 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2013 | 01 Jul 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2013 | 01 Jul 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2013 | 01 Jul 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2013 | 01 Jul 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jul 2013 | 01 Jul 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 12 Jun 2013 | 12 Jun 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Jun 2013 | 03 Jun 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 29 May 2013 | 28 May 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 03 May 2013 | 03 May 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2013 | 01 May 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2013 | 01 May 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2013 | 01 May 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2013 | 01 May 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2013 | 01 May 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 May 2013 | 01 May 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 30 Apr 2013 | 25 Apr 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | Q1 2013 FORM 8-K | 25 Apr 2013 | 25 Apr 2013 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10Q MARCH 31, 2013 | 25 Apr 2013 | 31 Mar 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Apr 2013 | 01 Apr 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 21 Mar 2013 | 21 Mar 2013 | 001-10499 |
| ARS | Open ARS document | View SEC filing for ARS | AUTO-GENERATED PAPER DOCUMENT | 12 Mar 2013 | 31 Dec 2012 | 001-10499 |
| DEFA14A | Open DEFA14A document | View SEC filing for DEFA14A | DEFA14A | 08 Mar 2013 | 001-10499 | |
| DEF 14A | Open DEF 14A document | View SEC filing for DEF 14A | DEF 14A | 08 Mar 2013 | 25 Apr 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 04 Mar 2013 | 04 Mar 2013 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 28 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Mar 2013 | 01 Mar 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 22 Feb 2013 | 21 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 22 Feb 2013 | 21 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 22 Feb 2013 | 21 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 22 Feb 2013 | 21 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 22 Feb 2013 | 21 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 22 Feb 2013 | 21 Feb 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 19 Feb 2013 | 19 Feb 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 19 Feb 2013 | 13 Feb 2013 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 14 Feb 2013 | 14 Feb 2013 | 001-10499 |
| 10-K | Open 10-K document | Open XBRL data | View SEC filing for 10-K | 10-K | 14 Feb 2013 | 31 Dec 2012 | 001-10499 |
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | MUNDER 13G FILING FOR NORTHWESTERN CORPORATION | 13 Feb 2013 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | NWE AS OF 12/31/12 | 11 Feb 2013 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 11 Feb 2013 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2013 | 01 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2013 | 01 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2013 | 01 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2013 | 01 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2013 | 01 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2013 | 01 Feb 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Feb 2013 | 01 Feb 2013 | |
| SC 13G | Open SC 13G document | View SEC filing for SC 13G | NORTHWESTERN CORPORATION SC 13G | 29 Jan 2013 | 005-36015 | |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 11 Jan 2013 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 31 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 31 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 31 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 31 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 31 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 31 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 02 Jan 2013 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Jan 2013 | 02 Jan 2013 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 18 Dec 2012 | 12 Dec 2012 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 10 Dec 2012 | 10 Dec 2012 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 04 Dec 2012 | 04 Dec 2012 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Dec 2012 | 03 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Dec 2012 | 03 Dec 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Dec 2012 | 03 Dec 2012 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 09 Nov 2012 | 09 Nov 2012 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 09 Nov 2012 | 09 Nov 2012 | 001-10499 |
| SC 13G/A | Open SC 13G/A document | View SEC filing for SC 13G/A | 09 Nov 2012 | 005-36015 | ||
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Nov 2012 | 01 Nov 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Nov 2012 | 01 Nov 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Nov 2012 | 01 Nov 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Nov 2012 | 01 Nov 2012 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | FORM 8-K EARNINGS RELEASE Q3 2012 | 24 Oct 2012 | 24 Oct 2012 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | 10-Q | 24 Oct 2012 | 30 Sep 2012 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 11 Oct 2012 | 05 Oct 2012 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2012 | 01 Oct 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2012 | 01 Oct 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2012 | 01 Oct 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2012 | 01 Oct 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2012 | 01 Oct 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2012 | 01 Oct 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 02 Oct 2012 | 01 Oct 2012 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 02 Oct 2012 | 01 Oct 2012 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K DGGS INITIAL DECISION | 27 Sep 2012 | 26 Sep 2012 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 04 Sep 2012 | 04 Sep 2012 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K | 04 Sep 2012 | 04 Sep 2012 | 001-10499 |
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 30 Aug 2012 | |||
| CORRESP | Open CORRESP document | View SEC filing for CORRESP | 24 Aug 2012 | |||
| UPLOAD | Open UPLOAD document | View SEC filing for UPLOAD | 14 Aug 2012 | |||
| 8-K | Open 8-K document | View SEC filing for 8-K | 14 Aug 2012 | 10 Aug 2012 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Aug 2012 | 01 Aug 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Aug 2012 | 01 Aug 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Aug 2012 | 01 Aug 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Aug 2012 | 01 Aug 2012 | |
| S-3ASR | Open S-3ASR document | View SEC filing for S-3ASR | 27 Jul 2012 | 333-182895 | ||
| RW | Open RW document | View SEC filing for RW | 27 Jul 2012 | 333-182837 | ||
| 8-K | Open 8-K document | View SEC filing for 8-K | 26 Jul 2012 | 24 Jul 2012 | 001-10499 | |
| S-3 | Open S-3 document | View SEC filing for S-3 | REGISTRATION STATEMENT | 25 Jul 2012 | 333-182837 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | FORM 8-K PRESS RELEASE Q2 2012 | 24 Jul 2012 | 24 Jul 2012 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10Q FOR JUNE 30, 2012 | 24 Jul 2012 | 30 Jun 2012 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jul 2012 | 02 Jul 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jul 2012 | 02 Jul 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jul 2012 | 02 Jul 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jul 2012 | 02 Jul 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jul 2012 | 02 Jul 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jul 2012 | 02 Jul 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 03 Jul 2012 | 02 Jul 2012 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 12 Jun 2012 | 12 Jun 2012 | 001-10499 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 01 Jun 2012 | 01 Jun 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 | 31 May 2012 | 30 May 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 01 May 2012 | 01 May 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 01 May 2012 | 01 May 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 01 May 2012 | 01 May 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 01 May 2012 | 01 May 2012 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K_04/27/2012_VOTING RESULTS | 27 Apr 2012 | 27 Apr 2012 | 001-10499 |
| 424B5 | Open 424B5 document | View SEC filing for 424B5 | FORM 424(B)(5)_PROSPECTUS SUPPLEMENT | 25 Apr 2012 | 333-179568 | |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K _ 04/25/2012 | 25 Apr 2012 | 25 Apr 2012 | 001-10499 |
| 8-K | Open 8-K document | View SEC filing for 8-K | 8-K_04/25/2012_EARNINGS RELEASE | 25 Apr 2012 | 25 Apr 2012 | 001-10499 |
| 10-Q | Open 10-Q document | Open XBRL data | View SEC filing for 10-Q | FORM 10-Q MARCH 31, 2012 | 25 Apr 2012 | 31 Mar 2012 | 001-10499 |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 30 Mar 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 30 Mar 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 30 Mar 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 30 Mar 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 30 Mar 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 30 Mar 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 02 Apr 2012 | |
| 4 | Open 4 document | View SEC filing for 4 | FORM 4 - GENERATED BY WEBFILINGS | 03 Apr 2012 | 02 Apr 2012 |
NORTHWESTERN CORP files with the SEC under CIK 0000073088. This page aggregates EDGAR filings and related ownership activity.
Industry: Electric & Other Services Combined.