Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000110019-19-000003-index-headers.html | 2019-02-21 08:52:20 | |
| 0000110019-19-000003-index.html | 2019-02-21 08:52:20 | |
| 0000110019-19-000003.txt | 2019-02-21 08:52:20 | |
 0000110019-19-000003-xbrl.zip | 140788 | 2019-02-21 08:52:20 |
| FilingSummary.xml | 20902 | 2019-02-21 08:52:20 |
| Financial_Report.xlsx | 60838 | 2019-02-21 08:52:20 |
| nwp-20181231.xml | 570047 | 2019-02-21 08:52:20 |
| nwp-20181231.xsd | 30443 | 2019-02-21 08:52:20 |
| nwp-20181231_cal.xml | 62273 | 2019-02-21 08:52:20 |
| nwp-20181231_def.xml | 139255 | 2019-02-21 08:52:20 |
| nwp-20181231_lab.xml | 476267 | 2019-02-21 08:52:20 |
| nwp-20181231_pre.xml | 264273 | 2019-02-21 08:52:20 |
| nwp_20181231x10k.htm | 810901 | 2019-02-21 08:52:20 |
| nwp_20181231xex-231.htm | 3142 | 2019-02-21 08:52:20 |
| nwp_20181231xex-311.htm | 12746 | 2019-02-21 08:52:20 |
| nwp_20181231xex-312.htm | 12885 | 2019-02-21 08:52:20 |
| nwp_20181231xex-32.htm | 7720 | 2019-02-21 08:52:20 |
| R1.htm | 33263 | 2019-02-21 08:52:20 |
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| R31.htm | 13976 | 2019-02-21 08:52:20 |
| R32.htm | 35250 | 2019-02-21 08:52:20 |
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| R6.htm | 55809 | 2019-02-21 08:52:20 |
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| R8.htm | 11260 | 2019-02-21 08:52:20 |
| R9.htm | 37827 | 2019-02-21 08:52:20 |
| report.css | 2767 | 2019-02-21 08:52:20 |
| Show.js | 1085 | 2019-02-21 08:52:20 |