Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000110019-18-000003-index-headers.html | 2018-02-22 09:02:52 | |
| 0000110019-18-000003-index.html | 2018-02-22 09:02:52 | |
| 0000110019-18-000003.txt | 2018-02-22 09:02:52 | |
 0000110019-18-000003-xbrl.zip | 130733 | 2018-02-22 09:02:52 |
| FilingSummary.xml | 19022 | 2018-02-22 09:02:52 |
| Financial_Report.xlsx | 53098 | 2018-02-22 09:02:52 |
| nwp-20171231.xml | 483633 | 2018-02-22 09:02:52 |
| nwp-20171231.xsd | 28140 | 2018-02-22 09:02:52 |
| nwp-20171231_cal.xml | 61819 | 2018-02-22 09:02:52 |
| nwp-20171231_def.xml | 130984 | 2018-02-22 09:02:52 |
| nwp-20171231_lab.xml | 473292 | 2018-02-22 09:02:52 |
| nwp-20171231_pre.xml | 260902 | 2018-02-22 09:02:52 |
| nwp_20161231xex-3111.htm | 12747 | 2018-02-22 09:02:52 |
| nwp_20161231xex-3121.htm | 12886 | 2018-02-22 09:02:52 |
| nwp_20161231xex-321.htm | 7721 | 2018-02-22 09:02:52 |
| nwp_20171231x10k.htm | 785854 | 2018-02-22 09:02:52 |
| nwp_20171231xex-231.htm | 3142 | 2018-02-22 09:02:52 |
| R1.htm | 27764 | 2018-02-22 09:02:52 |
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| R28.htm | 30695 | 2018-02-22 09:02:52 |
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| R8.htm | 11658 | 2018-02-22 09:02:52 |
| R9.htm | 41243 | 2018-02-22 09:02:52 |
| report.css | 2767 | 2018-02-22 09:02:52 |
| Show.js | 1410 | 2018-02-22 09:02:52 |