Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001733998-19-000004-index-headers.html | 2019-03-01 17:23:38 | |
| 0001733998-19-000004-index.html | 2019-03-01 17:23:38 | |
| 0001733998-19-000004.txt | 2019-03-01 17:23:38 | |
 0001733998-19-000004-xbrl.zip | 573983 | 2019-03-01 17:23:38 |
| a10cc_rsuagreement2019.htm | 84833 | 2019-03-01 17:23:38 |
| a10ii_directorrsuagreement.htm | 36366 | 2019-03-01 17:23:38 |
| a10l_nwnaturalgasindemnity.htm | 52824 | 2019-03-01 17:23:38 |
| a10m_nwholdingindemnityagr.htm | 57600 | 2019-03-01 17:23:38 |
| a10q_executiveannualincent.htm | 70099 | 2019-03-01 17:23:38 |
| a10ss_2019nwngsnbuaipplan.htm | 16582 | 2019-03-01 17:23:38 |
| a10z_pspawardagreement2019.htm | 78650 | 2019-03-01 17:23:38 |
| ex2112312018.htm | 31894 | 2019-03-01 17:23:38 |
| ex23bconsentofpublicaccoun.htm | 2222 | 2019-03-01 17:23:38 |
| ex23consentofpublicaccount.htm | 2536 | 2019-03-01 17:23:38 |
| ex31aq42018_da.htm | 8806 | 2019-03-01 17:23:38 |
| ex31bq42018_fb.htm | 8961 | 2019-03-01 17:23:38 |
| ex31cq42018_da.htm | 8937 | 2019-03-01 17:23:38 |
| ex31dq42018_fb.htm | 8967 | 2019-03-01 17:23:38 |
| ex32aq42018_dafb.htm | 5659 | 2019-03-01 17:23:38 |
| ex32bq42018_dafb.htm | 5802 | 2019-03-01 17:23:38 |
| FilingSummary.xml | 54021 | 2019-03-01 17:23:38 |
| Financial_Report.xlsx | 184496 | 2019-03-01 17:23:38 |
| form10-k2018.htm | 4724589 | 2019-03-01 17:23:38 |
| nwn-20181231.xml | 5782976 | 2019-03-01 17:23:38 |
| nwn-20181231.xsd | 108074 | 2019-03-01 17:23:38 |
| nwn-20181231_cal.xml | 156764 | 2019-03-01 17:23:38 |
| nwn-20181231_def.xml | 873247 | 2019-03-01 17:23:38 |
| nwn-20181231_lab.xml | 1424187 | 2019-03-01 17:23:38 |
| nwn-20181231_pre.xml | 981278 | 2019-03-01 17:23:38 |
 nwn4chz.jpg | 38736 | 2019-03-01 17:23:38 |
 nwnholdingshza01.jpg | 57055 | 2019-03-01 17:23:38 |
| R1.htm | 39900 | 2019-03-01 17:23:38 |
| R10.htm | 54140 | 2019-03-01 17:23:38 |
| R11.htm | 124558 | 2019-03-01 17:23:38 |
| R12.htm | 21459 | 2019-03-01 17:23:38 |
| R13.htm | 65278 | 2019-03-01 17:23:38 |
| R14.htm | 128088 | 2019-03-01 17:23:38 |
| R15.htm | 113488 | 2019-03-01 17:23:38 |
| R16.htm | 434138 | 2019-03-01 17:23:38 |
| R17.htm | 167111 | 2019-03-01 17:23:38 |
| R18.htm | 49481 | 2019-03-01 17:23:38 |
| R19.htm | 25076 | 2019-03-01 17:23:38 |
| R2.htm | 101436 | 2019-03-01 17:23:38 |
| R20.htm | 31301 | 2019-03-01 17:23:38 |
| R21.htm | 9891 | 2019-03-01 17:23:38 |
| R22.htm | 71803 | 2019-03-01 17:23:38 |
| R23.htm | 49957 | 2019-03-01 17:23:38 |
| R24.htm | 88664 | 2019-03-01 17:23:38 |
| R25.htm | 153706 | 2019-03-01 17:23:38 |
| R26.htm | 157641 | 2019-03-01 17:23:38 |
| R27.htm | 82167 | 2019-03-01 17:23:38 |
| R28.htm | 98639 | 2019-03-01 17:23:38 |
| R29.htm | 192125 | 2019-03-01 17:23:38 |
| R3.htm | 8107 | 2019-03-01 17:23:38 |
| R30.htm | 79677 | 2019-03-01 17:23:38 |
| R31.htm | 53007 | 2019-03-01 17:23:38 |
| R32.htm | 116282 | 2019-03-01 17:23:38 |
| R33.htm | 14712 | 2019-03-01 17:23:38 |
| R34.htm | 51443 | 2019-03-01 17:23:38 |
| R35.htm | 123643 | 2019-03-01 17:23:38 |
| R36.htm | 97033 | 2019-03-01 17:23:38 |
| R37.htm | 423004 | 2019-03-01 17:23:38 |
| R38.htm | 156613 | 2019-03-01 17:23:38 |
| R39.htm | 45608 | 2019-03-01 17:23:38 |
| R4.htm | 156058 | 2019-03-01 17:23:38 |
| R40.htm | 19458 | 2019-03-01 17:23:38 |
| R41.htm | 24177 | 2019-03-01 17:23:38 |
| R42.htm | 57786 | 2019-03-01 17:23:38 |
| R43.htm | 42456 | 2019-03-01 17:23:38 |
| R44.htm | 57396 | 2019-03-01 17:23:38 |
| R45.htm | 156355 | 2019-03-01 17:23:38 |
| R46.htm | 159804 | 2019-03-01 17:23:38 |
| R47.htm | 82400 | 2019-03-01 17:23:38 |
| R48.htm | 100173 | 2019-03-01 17:23:38 |
| R49.htm | 27936 | 2019-03-01 17:23:38 |
| R5.htm | 10685 | 2019-03-01 17:23:38 |
| R50.htm | 22687 | 2019-03-01 17:23:38 |
| R51.htm | 76437 | 2019-03-01 17:23:38 |
| R52.htm | 8388 | 2019-03-01 17:23:38 |
| R53.htm | 30262 | 2019-03-01 17:23:38 |
| R54.htm | 7952 | 2019-03-01 17:23:38 |
| R55.htm | 65204 | 2019-03-01 17:23:38 |
| R56.htm | 38849 | 2019-03-01 17:23:38 |
| R57.htm | 93335 | 2019-03-01 17:23:38 |
| R58.htm | 22282 | 2019-03-01 17:23:38 |
| R59.htm | 53263 | 2019-03-01 17:23:38 |
| R6.htm | 46859 | 2019-03-01 17:23:38 |
| R60.htm | 19007 | 2019-03-01 17:23:38 |
| R61.htm | 133588 | 2019-03-01 17:23:38 |
| R62.htm | 20787 | 2019-03-01 17:23:38 |
| R63.htm | 175091 | 2019-03-01 17:23:38 |
| R64.htm | 165538 | 2019-03-01 17:23:38 |
| R65.htm | 49821 | 2019-03-01 17:23:38 |
| R66.htm | 82672 | 2019-03-01 17:23:38 |
| R67.htm | 31875 | 2019-03-01 17:23:38 |
| R68.htm | 21210 | 2019-03-01 17:23:38 |
| R69.htm | 23547 | 2019-03-01 17:23:38 |
| R7.htm | 116046 | 2019-03-01 17:23:38 |
| R70.htm | 23437 | 2019-03-01 17:23:38 |
| R71.htm | 34519 | 2019-03-01 17:23:38 |
| R72.htm | 27368 | 2019-03-01 17:23:38 |
| R73.htm | 13286 | 2019-03-01 17:23:38 |
| R74.htm | 32713 | 2019-03-01 17:23:38 |
| R75.htm | 65987 | 2019-03-01 17:23:38 |
| R76.htm | 123313 | 2019-03-01 17:23:38 |
| R77.htm | 45098 | 2019-03-01 17:23:38 |
| R78.htm | 25115 | 2019-03-01 17:23:38 |
| R79.htm | 23817 | 2019-03-01 17:23:38 |
| R8.htm | 22839 | 2019-03-01 17:23:38 |
| R80.htm | 18748 | 2019-03-01 17:23:38 |
| R81.htm | 32045 | 2019-03-01 17:23:38 |
| R82.htm | 13426 | 2019-03-01 17:23:38 |
| R83.htm | 22514 | 2019-03-01 17:23:38 |
| R84.htm | 16979 | 2019-03-01 17:23:38 |
| R85.htm | 40422 | 2019-03-01 17:23:38 |
| R86.htm | 20529 | 2019-03-01 17:23:38 |
| R87.htm | 32601 | 2019-03-01 17:23:38 |
| R88.htm | 91657 | 2019-03-01 17:23:38 |
| R89.htm | 189920 | 2019-03-01 17:23:38 |
| R9.htm | 295289 | 2019-03-01 17:23:38 |
| R90.htm | 61308 | 2019-03-01 17:23:38 |
| R91.htm | 187068 | 2019-03-01 17:23:38 |
| R92.htm | 15716 | 2019-03-01 17:23:38 |
| report.css | 2768 | 2019-03-01 17:23:38 |
| Show.js | 1086 | 2019-03-01 17:23:38 |