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|---|---|---|
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| 0000080172-17-000039-index.html | 2017-08-11 16:01:10 | |
| 0000080172-17-000039.txt | 2017-08-11 16:01:10 | |
 0000080172-17-000039-xbrl.zip | 59163 | 2017-08-11 16:01:10 |
| FilingSummary.xml | 17017 | 2017-08-11 16:01:10 |
| Financial_Report.xlsx | 33502 | 2017-08-11 16:01:10 |
| npk-20170702.xml | 717284 | 2017-08-11 16:01:10 |
| npk-20170702.xsd | 17795 | 2017-08-11 16:01:10 |
| npk-20170702x10q.htm | 903419 | 2017-08-11 16:01:10 |
| npk-20170702xex10_1.htm | 120076 | 2017-08-11 16:01:10 |
| npk-20170702xex10_2.htm | 46248 | 2017-08-11 16:01:10 |
| npk-20170702xex31_1.htm | 15362 | 2017-08-11 16:01:10 |
| npk-20170702xex31_2.htm | 15643 | 2017-08-11 16:01:10 |
| npk-20170702xex32_1.htm | 8865 | 2017-08-11 16:01:10 |
| npk-20170702xex32_2.htm | 9062 | 2017-08-11 16:01:10 |
| npk-20170702_cal.xml | 51353 | 2017-08-11 16:01:10 |
| npk-20170702_def.xml | 54226 | 2017-08-11 16:01:10 |
| npk-20170702_lab.xml | 160929 | 2017-08-11 16:01:10 |
| npk-20170702_pre.xml | 145480 | 2017-08-11 16:01:10 |
| R1.htm | 20398 | 2017-08-11 16:01:10 |
| R10.htm | 9198 | 2017-08-11 16:01:10 |
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| R9.htm | 161090 | 2017-08-11 16:01:10 |
| report.css | 2767 | 2017-08-11 16:01:10 |
| Show.js | 1410 | 2017-08-11 16:01:10 |