Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001733998-23-000003-index-headers.html | 2023-01-06 14:29:15 | |
| 0001733998-23-000003-index.html | 2023-01-06 14:29:15 | |
| 0001733998-23-000003.txt | 2023-01-06 14:29:15 | |
 0001733998-23-000003-xbrl.zip | 114026 | 2023-01-06 14:29:15 |
| exhibit41nwn25thsupplement.htm | 164212 | 2023-01-06 14:29:15 |
| FilingSummary.xml | 1883 | 2023-01-06 14:29:15 |
| Financial_Report.xlsx | 6035 | 2023-01-06 14:29:15 |
| MetaLinks.json | 22658 | 2023-01-06 14:29:15 |
| nwn-20230106.htm | 61301 | 2023-01-06 14:29:15 |
| nwn-20230106.xsd | 2939 | 2023-01-06 14:29:15 |
| nwn-20230106_def.xml | 16431 | 2023-01-06 14:29:15 |
 nwn-20230106_g1.jpg | 57055 | 2023-01-06 14:29:15 |
 nwn-20230106_g2.jpg | 38736 | 2023-01-06 14:29:15 |
| nwn-20230106_htm.xml | 20629 | 2023-01-06 14:29:15 |
| nwn-20230106_lab.xml | 31891 | 2023-01-06 14:29:15 |
| nwn-20230106_pre.xml | 16703 | 2023-01-06 14:29:15 |
| R1.htm | 45116 | 2023-01-06 14:29:15 |
| report.css | 2767 | 2023-01-06 14:29:15 |
| Show.js | 1085 | 2023-01-06 14:29:15 |