Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001733998-20-000006-index-headers.html | 2020-03-02 13:44:26 | |
| 0001733998-20-000006-index.html | 2020-03-02 13:44:26 | |
| 0001733998-20-000006.txt | 2020-03-02 13:44:26 | |
 0001733998-20-000006-xbrl.zip | 897529 | 2020-03-02 13:44:26 |
| a10ll2019nwngsnbuaippl.htm | 16776 | 2020-03-02 13:44:26 |
| ex10aarsuagreement2020.htm | 92663 | 2020-03-02 13:44:26 |
| ex10oexecutiveannualin.htm | 76510 | 2020-03-02 13:44:26 |
| ex10qcicagrmt2020.htm | 65861 | 2020-03-02 13:44:26 |
| ex10xltipagrmt2020-2022.htm | 87970 | 2020-03-02 13:44:26 |
| ex2112312019.htm | 48422 | 2020-03-02 13:44:26 |
| ex23a2019consentofpubl.htm | 2284 | 2020-03-02 13:44:26 |
| ex23b2019consentofpubl.htm | 2111 | 2020-03-02 13:44:26 |
| ex311q42019ceo.htm | 9053 | 2020-03-02 13:44:26 |
| ex312q42019cfo.htm | 9208 | 2020-03-02 13:44:26 |
| ex313q42019ceo.htm | 9125 | 2020-03-02 13:44:26 |
| ex314q42019cfo.htm | 9214 | 2020-03-02 13:44:26 |
| ex321q42019ceocfo.htm | 5900 | 2020-03-02 13:44:26 |
| ex322q42019ceocfo.htm | 6043 | 2020-03-02 13:44:26 |
| ex4jdescriptionofsecur.htm | 25481 | 2020-03-02 13:44:26 |
| FilingSummary.xml | 64246 | 2020-03-02 13:44:26 |
| Financial_Report.xlsx | 202122 | 2020-03-02 13:44:26 |
| form10-k20191.htm | 6491824 | 2020-03-02 13:44:26 |
| form10-k20191_htm.xml | 6012633 | 2020-03-02 13:44:26 |
| MetaLinks.json | 1209183 | 2020-03-02 13:44:26 |
| nwn-20191231.xsd | 116219 | 2020-03-02 13:44:26 |
| nwn-20191231_cal.xml | 161715 | 2020-03-02 13:44:26 |
| nwn-20191231_def.xml | 1001911 | 2020-03-02 13:44:26 |
| nwn-20191231_lab.xml | 1565096 | 2020-03-02 13:44:26 |
| nwn-20191231_pre.xml | 1114343 | 2020-03-02 13:44:26 |
 nwn4chza30.jpg | 38736 | 2020-03-02 13:44:26 |
 nwnholdingshza33.jpg | 57055 | 2020-03-02 13:44:26 |
| R1.htm | 72266 | 2020-03-02 13:44:26 |
| R10.htm | 47853 | 2020-03-02 13:44:26 |
| R100.htm | 101018 | 2020-03-02 13:44:26 |
| R101.htm | 144170 | 2020-03-02 13:44:26 |
| R102.htm | 12845 | 2020-03-02 13:44:26 |
| R103.htm | 61302 | 2020-03-02 13:44:26 |
| R104.htm | 261281 | 2020-03-02 13:44:26 |
| R105.htm | 15893 | 2020-03-02 13:44:26 |
| R11.htm | 112907 | 2020-03-02 13:44:26 |
| R12.htm | 23531 | 2020-03-02 13:44:26 |
| R13.htm | 104408 | 2020-03-02 13:44:26 |
| R14.htm | 128043 | 2020-03-02 13:44:26 |
| R15.htm | 109444 | 2020-03-02 13:44:26 |
| R16.htm | 117714 | 2020-03-02 13:44:26 |
| R17.htm | 409022 | 2020-03-02 13:44:26 |
| R18.htm | 165639 | 2020-03-02 13:44:26 |
| R19.htm | 48478 | 2020-03-02 13:44:26 |
| R2.htm | 101460 | 2020-03-02 13:44:26 |
| R20.htm | 23549 | 2020-03-02 13:44:26 |
| R21.htm | 29978 | 2020-03-02 13:44:26 |
| R22.htm | 23999 | 2020-03-02 13:44:26 |
| R23.htm | 64870 | 2020-03-02 13:44:26 |
| R24.htm | 33170 | 2020-03-02 13:44:26 |
| R25.htm | 84874 | 2020-03-02 13:44:26 |
| R26.htm | 104121 | 2020-03-02 13:44:26 |
| R27.htm | 7366 | 2020-03-02 13:44:26 |
| R28.htm | 146552 | 2020-03-02 13:44:26 |
| R29.htm | 134685 | 2020-03-02 13:44:26 |
| R3.htm | 8292 | 2020-03-02 13:44:26 |
| R30.htm | 89000 | 2020-03-02 13:44:26 |
| R31.htm | 177334 | 2020-03-02 13:44:26 |
| R32.htm | 75215 | 2020-03-02 13:44:26 |
| R33.htm | 46882 | 2020-03-02 13:44:26 |
| R34.htm | 104473 | 2020-03-02 13:44:26 |
| R35.htm | 17933 | 2020-03-02 13:44:26 |
| R36.htm | 47311 | 2020-03-02 13:44:26 |
| R37.htm | 124629 | 2020-03-02 13:44:26 |
| R38.htm | 76466 | 2020-03-02 13:44:26 |
| R39.htm | 113836 | 2020-03-02 13:44:26 |
| R4.htm | 153806 | 2020-03-02 13:44:26 |
| R40.htm | 395367 | 2020-03-02 13:44:26 |
| R41.htm | 153430 | 2020-03-02 13:44:26 |
| R42.htm | 41895 | 2020-03-02 13:44:26 |
| R43.htm | 17851 | 2020-03-02 13:44:26 |
| R44.htm | 22789 | 2020-03-02 13:44:26 |
| R45.htm | 12367 | 2020-03-02 13:44:26 |
| R46.htm | 50411 | 2020-03-02 13:44:26 |
| R47.htm | 28814 | 2020-03-02 13:44:26 |
| R48.htm | 52258 | 2020-03-02 13:44:26 |
| R49.htm | 107471 | 2020-03-02 13:44:26 |
| R5.htm | 10689 | 2020-03-02 13:44:26 |
| R50.htm | 148449 | 2020-03-02 13:44:26 |
| R51.htm | 133498 | 2020-03-02 13:44:26 |
| R52.htm | 60514 | 2020-03-02 13:44:26 |
| R53.htm | 25464 | 2020-03-02 13:44:26 |
| R54.htm | 53076 | 2020-03-02 13:44:26 |
| R55.htm | 90572 | 2020-03-02 13:44:26 |
| R56.htm | 28257 | 2020-03-02 13:44:26 |
| R57.htm | 23021 | 2020-03-02 13:44:26 |
| R58.htm | 86867 | 2020-03-02 13:44:26 |
| R59.htm | 14522 | 2020-03-02 13:44:26 |
| R6.htm | 49590 | 2020-03-02 13:44:26 |
| R60.htm | 20741 | 2020-03-02 13:44:26 |
| R61.htm | 6950 | 2020-03-02 13:44:26 |
| R62.htm | 65199 | 2020-03-02 13:44:26 |
| R63.htm | 38911 | 2020-03-02 13:44:26 |
| R64.htm | 84357 | 2020-03-02 13:44:26 |
| R65.htm | 22293 | 2020-03-02 13:44:26 |
| R66.htm | 41072 | 2020-03-02 13:44:26 |
| R67.htm | 19833 | 2020-03-02 13:44:26 |
| R68.htm | 133656 | 2020-03-02 13:44:26 |
| R69.htm | 25120 | 2020-03-02 13:44:26 |
| R7.htm | 125129 | 2020-03-02 13:44:26 |
| R70.htm | 78547 | 2020-03-02 13:44:26 |
| R71.htm | 21929 | 2020-03-02 13:44:26 |
| R72.htm | 104202 | 2020-03-02 13:44:26 |
| R73.htm | 165861 | 2020-03-02 13:44:26 |
| R74.htm | 85706 | 2020-03-02 13:44:26 |
| R75.htm | 39818 | 2020-03-02 13:44:26 |
| R76.htm | 7376 | 2020-03-02 13:44:26 |
| R77.htm | 13594 | 2020-03-02 13:44:26 |
| R78.htm | 43436 | 2020-03-02 13:44:26 |
| R79.htm | 67681 | 2020-03-02 13:44:26 |
| R8.htm | 25957 | 2020-03-02 13:44:26 |
| R80.htm | 28820 | 2020-03-02 13:44:26 |
| R81.htm | 21199 | 2020-03-02 13:44:26 |
| R82.htm | 26709 | 2020-03-02 13:44:26 |
| R83.htm | 23440 | 2020-03-02 13:44:26 |
| R84.htm | 44146 | 2020-03-02 13:44:26 |
| R85.htm | 30999 | 2020-03-02 13:44:26 |
| R86.htm | 13289 | 2020-03-02 13:44:26 |
| R87.htm | 32716 | 2020-03-02 13:44:26 |
| R88.htm | 64485 | 2020-03-02 13:44:26 |
| R89.htm | 141059 | 2020-03-02 13:44:26 |
| R9.htm | 138686 | 2020-03-02 13:44:26 |
| R90.htm | 57338 | 2020-03-02 13:44:26 |
| R91.htm | 25119 | 2020-03-02 13:44:26 |
| R92.htm | 23339 | 2020-03-02 13:44:26 |
| R93.htm | 39402 | 2020-03-02 13:44:26 |
| R94.htm | 32046 | 2020-03-02 13:44:26 |
| R95.htm | 14103 | 2020-03-02 13:44:26 |
| R96.htm | 18628 | 2020-03-02 13:44:26 |
| R97.htm | 16935 | 2020-03-02 13:44:26 |
| R98.htm | 13375 | 2020-03-02 13:44:26 |
| R99.htm | 32613 | 2020-03-02 13:44:26 |
| report.css | 2768 | 2020-03-02 13:44:26 |
| Show.js | 1086 | 2020-03-02 13:44:26 |