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|---|---|---|
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| 0000110019-21-000003-index.html | 2021-02-24 16:18:12 | |
| 0000110019-21-000003.txt | 2021-02-24 16:18:12 | |
 0000110019-21-000003-xbrl.zip | 209281 | 2021-02-24 16:18:12 |
| FilingSummary.xml | 22615 | 2021-02-24 16:18:12 |
| Financial_Report.xlsx | 69274 | 2021-02-24 16:18:12 |
| MetaLinks.json | 471367 | 2021-02-24 16:18:12 |
| nwp-20201231.htm | 1028493 | 2021-02-24 16:18:12 |
| nwp-20201231.xsd | 27272 | 2021-02-24 16:18:12 |
| nwp-20201231_cal.xml | 63203 | 2021-02-24 16:18:12 |
| nwp-20201231_def.xml | 143583 | 2021-02-24 16:18:12 |
| nwp-20201231_htm.xml | 694845 | 2021-02-24 16:18:12 |
| nwp-20201231_lab.xml | 443766 | 2021-02-24 16:18:12 |
| nwp-20201231_pre.xml | 272177 | 2021-02-24 16:18:12 |
| nwp_20201231xex-311.htm | 10245 | 2021-02-24 16:18:12 |
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| nwp_20201231xex-32.htm | 6495 | 2021-02-24 16:18:12 |
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| R9.htm | 5849 | 2021-02-24 16:18:12 |
| report.css | 2767 | 2021-02-24 16:18:12 |
| Show.js | 1085 | 2021-02-24 16:18:12 |