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| 0000073088-22-000094.txt | 2022-04-28 19:02:56 | |
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| ex311certificationq12022.htm | 10522 | 2022-04-28 19:02:56 |
| ex312certificationq12022.htm | 10397 | 2022-04-28 19:02:56 |
| ex321certificationq12022.htm | 4824 | 2022-04-28 19:02:56 |
| ex322certificationq12022.htm | 4827 | 2022-04-28 19:02:56 |
| FilingSummary.xml | 23696 | 2022-04-28 19:02:56 |
| Financial_Report.xlsx | 62487 | 2022-04-28 19:02:56 |
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| nwe-20220331.htm | 1788912 | 2022-04-28 19:02:56 |
| nwe-20220331.xsd | 33640 | 2022-04-28 19:02:56 |
| nwe-20220331_cal.xml | 88453 | 2022-04-28 19:02:56 |
| nwe-20220331_def.xml | 249150 | 2022-04-28 19:02:56 |
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| nwe-20220331_htm.xml | 1213755 | 2022-04-28 19:02:56 |
| nwe-20220331_lab.xml | 466271 | 2022-04-28 19:02:56 |
| nwe-20220331_pre.xml | 310627 | 2022-04-28 19:02:56 |
| R1.htm | 52335 | 2022-04-28 19:02:56 |
| R10.htm | 73665 | 2022-04-28 19:02:56 |
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| R2.htm | 73289 | 2022-04-28 19:02:56 |
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