Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001733998-24-000011-index-headers.html | 2024-02-23 15:05:21 | |
| 0001733998-24-000011-index.html | 2024-02-23 15:05:21 | |
| 0001733998-24-000011.txt | 2024-02-23 15:05:21 | |
 0001733998-24-000011-xbrl.zip | 935384 | 2024-02-23 15:05:21 |
| ex10bb2024rsuofficernon-of.htm | 83516 | 2024-02-23 15:05:21 |
| ex10ggamendmentofawardagre.htm | 7441 | 2024-02-23 15:05:21 |
| ex10mnorthwestnaturalgasco.htm | 34556 | 2024-02-23 15:05:21 |
| ex10snorthwestnaturalholdi.htm | 50558 | 2024-02-23 15:05:21 |
| ex10xperformancesharelongt.htm | 79101 | 2024-02-23 15:05:21 |
| ex2112312023.htm | 30586 | 2024-02-23 15:05:21 |
| ex23a2023consentofpublicac.htm | 2481 | 2024-02-23 15:05:21 |
| ex23b2023consentofpublicac.htm | 2329 | 2024-02-23 15:05:21 |
| ex311q42023_ceo.htm | 7610 | 2024-02-23 15:05:21 |
| ex312q42023_cfo.htm | 7689 | 2024-02-23 15:05:21 |
| ex313q42023_ceo.htm | 7632 | 2024-02-23 15:05:21 |
| ex314q42023_cfo.htm | 7667 | 2024-02-23 15:05:21 |
| ex321q4202_ceocfo.htm | 5389 | 2024-02-23 15:05:21 |
| ex322q42023_ceocfo.htm | 5471 | 2024-02-23 15:05:21 |
| ex4qnotepurchaseagreement.htm | 646334 | 2024-02-23 15:05:21 |
| ex4rnorthwestnaturalcibc.htm | 313909 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc001.jpg | 48658 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc002.jpg | 252993 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc003.jpg | 240733 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc004.jpg | 47637 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc005.jpg | 65873 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc006.jpg | 208920 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc007.jpg | 261494 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc008.jpg | 257007 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc009.jpg | 279838 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc010.jpg | 257865 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc011.jpg | 301756 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc012.jpg | 263472 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc013.jpg | 268205 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc014.jpg | 205341 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc015.jpg | 246122 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc016.jpg | 221353 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc017.jpg | 239830 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc018.jpg | 231264 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc019.jpg | 321651 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc020.jpg | 290595 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc021.jpg | 266713 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc022.jpg | 297707 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc023.jpg | 357359 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc024.jpg | 310565 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc025.jpg | 332976 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc026.jpg | 279087 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc027.jpg | 259403 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc028.jpg | 290476 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc029.jpg | 281885 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc030.jpg | 249762 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc031.jpg | 311369 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc032.jpg | 310706 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc033.jpg | 309980 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc034.jpg | 292006 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc035.jpg | 260207 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc036.jpg | 299038 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc037.jpg | 306848 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc038.jpg | 228834 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc039.jpg | 255995 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc040.jpg | 275744 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc041.jpg | 311414 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc042.jpg | 295461 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc043.jpg | 220809 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc044.jpg | 285637 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc045.jpg | 249325 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc046.jpg | 305862 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc047.jpg | 242108 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc048.jpg | 334203 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc049.jpg | 319060 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc050.jpg | 312902 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc051.jpg | 306112 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc052.jpg | 263468 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc053.jpg | 253958 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc054.jpg | 309430 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc055.jpg | 311126 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc056.jpg | 354255 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc057.jpg | 253124 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc058.jpg | 281330 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc059.jpg | 332149 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc060.jpg | 306449 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc061.jpg | 342579 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc062.jpg | 310598 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc063.jpg | 336866 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc064.jpg | 318236 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc065.jpg | 270578 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc066.jpg | 26533 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc067.jpg | 99668 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc068.jpg | 47892 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc069.jpg | 37516 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc070.jpg | 100210 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc071.jpg | 199678 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc072.jpg | 117680 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc073.jpg | 269048 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc074.jpg | 74152 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc075.jpg | 25460 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc076.jpg | 25509 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc077.jpg | 145058 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc078.jpg | 222560 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc079.jpg | 158054 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc080.jpg | 152865 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc081.jpg | 197575 | 2024-02-23 15:05:21 |
 ex4rnorthwestnaturalcibc082.jpg | 208709 | 2024-02-23 15:05:21 |
| ex97compensationclawbackpo.htm | 34840 | 2024-02-23 15:05:21 |
| FilingSummary.xml | 49639 | 2024-02-23 15:05:21 |
| Financial_Report.xlsx | 216347 | 2024-02-23 15:05:21 |
 incentiveformula.jpg | 43492 | 2024-02-23 15:05:21 |
| MetaLinks.json | 1421934 | 2024-02-23 15:05:21 |
| nwn-20231231.htm | 4226639 | 2024-02-23 15:05:21 |
| nwn-20231231.xsd | 108748 | 2024-02-23 15:05:21 |
| nwn-20231231_cal.xml | 124085 | 2024-02-23 15:05:21 |
| nwn-20231231_def.xml | 986505 | 2024-02-23 15:05:21 |
 nwn-20231231_g1.jpg | 57055 | 2024-02-23 15:05:21 |
 nwn-20231231_g2.jpg | 38736 | 2024-02-23 15:05:21 |
| nwn-20231231_htm.xml | 3527359 | 2024-02-23 15:05:21 |
| nwn-20231231_lab.xml | 1367720 | 2024-02-23 15:05:21 |
| nwn-20231231_pre.xml | 1086362 | 2024-02-23 15:05:21 |
| R1.htm | 76567 | 2024-02-23 15:05:21 |
| R10.htm | 80428 | 2024-02-23 15:05:21 |
| R11.htm | 103182 | 2024-02-23 15:05:21 |
| R12.htm | 162801 | 2024-02-23 15:05:21 |
| R13.htm | 61739 | 2024-02-23 15:05:21 |
| R14.htm | 128950 | 2024-02-23 15:05:21 |
| R15.htm | 107085 | 2024-02-23 15:05:21 |
| R16.htm | 33639 | 2024-02-23 15:05:21 |
| R17.htm | 23046 | 2024-02-23 15:05:21 |
| R18.htm | 44314 | 2024-02-23 15:05:21 |
| R19.htm | 26577 | 2024-02-23 15:05:21 |
| R2.htm | 9940 | 2024-02-23 15:05:21 |
| R20.htm | 69281 | 2024-02-23 15:05:21 |
| R21.htm | 7299 | 2024-02-23 15:05:21 |
| R22.htm | 57600 | 2024-02-23 15:05:21 |
| R23.htm | 447967 | 2024-02-23 15:05:21 |
| R24.htm | 22345 | 2024-02-23 15:05:21 |
| R25.htm | 71297 | 2024-02-23 15:05:21 |
| R26.htm | 17226 | 2024-02-23 15:05:21 |
| R27.htm | 89514 | 2024-02-23 15:05:21 |
| R28.htm | 160819 | 2024-02-23 15:05:21 |
| R29.htm | 68848 | 2024-02-23 15:05:21 |
| R3.htm | 108098 | 2024-02-23 15:05:21 |
| R30.htm | 74033 | 2024-02-23 15:05:21 |
| R31.htm | 262662 | 2024-02-23 15:05:21 |
| R32.htm | 104182 | 2024-02-23 15:05:21 |
| R33.htm | 31100 | 2024-02-23 15:05:21 |
| R34.htm | 18158 | 2024-02-23 15:05:21 |
| R35.htm | 27089 | 2024-02-23 15:05:21 |
| R36.htm | 22134 | 2024-02-23 15:05:21 |
| R37.htm | 38576 | 2024-02-23 15:05:21 |
| R38.htm | 130618 | 2024-02-23 15:05:21 |
| R39.htm | 59324 | 2024-02-23 15:05:21 |
| R4.htm | 177100 | 2024-02-23 15:05:21 |
| R40.htm | 144423 | 2024-02-23 15:05:21 |
| R41.htm | 51508 | 2024-02-23 15:05:21 |
| R42.htm | 42451 | 2024-02-23 15:05:21 |
| R43.htm | 32530 | 2024-02-23 15:05:21 |
| R44.htm | 58408 | 2024-02-23 15:05:21 |
| R45.htm | 47647 | 2024-02-23 15:05:21 |
| R46.htm | 61302 | 2024-02-23 15:05:21 |
| R47.htm | 38256 | 2024-02-23 15:05:21 |
| R48.htm | 53000 | 2024-02-23 15:05:21 |
| R49.htm | 23681 | 2024-02-23 15:05:21 |
| R5.htm | 55161 | 2024-02-23 15:05:21 |
| R50.htm | 96985 | 2024-02-23 15:05:21 |
| R51.htm | 33410 | 2024-02-23 15:05:21 |
| R52.htm | 102987 | 2024-02-23 15:05:21 |
| R53.htm | 42458 | 2024-02-23 15:05:21 |
| R54.htm | 93491 | 2024-02-23 15:05:21 |
| R55.htm | 92375 | 2024-02-23 15:05:21 |
| R56.htm | 13033 | 2024-02-23 15:05:21 |
| R57.htm | 15212 | 2024-02-23 15:05:21 |
| R58.htm | 21018 | 2024-02-23 15:05:21 |
| R59.htm | 299395 | 2024-02-23 15:05:21 |
| R6.htm | 134545 | 2024-02-23 15:05:21 |
| R60.htm | 63473 | 2024-02-23 15:05:21 |
| R61.htm | 37024 | 2024-02-23 15:05:21 |
| R62.htm | 29002 | 2024-02-23 15:05:21 |
| R63.htm | 21157 | 2024-02-23 15:05:21 |
| R64.htm | 26424 | 2024-02-23 15:05:21 |
| R65.htm | 22860 | 2024-02-23 15:05:21 |
| R66.htm | 41620 | 2024-02-23 15:05:21 |
| R67.htm | 39888 | 2024-02-23 15:05:21 |
| R68.htm | 53209 | 2024-02-23 15:05:21 |
| R69.htm | 111860 | 2024-02-23 15:05:21 |
| R7.htm | 58097 | 2024-02-23 15:05:21 |
| R70.htm | 43090 | 2024-02-23 15:05:21 |
| R71.htm | 79750 | 2024-02-23 15:05:21 |
| R72.htm | 95922 | 2024-02-23 15:05:21 |
| R73.htm | 35358 | 2024-02-23 15:05:21 |
| R74.htm | 14997 | 2024-02-23 15:05:21 |
| R75.htm | 26924 | 2024-02-23 15:05:21 |
| R76.htm | 6375 | 2024-02-23 15:05:21 |
| R77.htm | 17125 | 2024-02-23 15:05:21 |
| R78.htm | 32998 | 2024-02-23 15:05:21 |
| R79.htm | 96522 | 2024-02-23 15:05:21 |
| R8.htm | 8188 | 2024-02-23 15:05:21 |
| R80.htm | 20607 | 2024-02-23 15:05:21 |
| R81.htm | 203858 | 2024-02-23 15:05:21 |
| R82.htm | 15744 | 2024-02-23 15:05:21 |
| R9.htm | 24695 | 2024-02-23 15:05:21 |
| report.css | 2768 | 2024-02-23 15:05:21 |
| Show.js | 1086 | 2024-02-23 15:05:21 |