Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000080172-16-000050-index-headers.html | 2016-05-13 16:12:45 | |
| 0000080172-16-000050-index.html | 2016-05-13 16:12:45 | |
| 0000080172-16-000050.txt | 2016-05-13 16:12:45 | |
 0000080172-16-000050-xbrl.zip | 41510 | 2016-05-13 16:12:45 |
| FilingSummary.xml | 13008 | 2016-05-13 16:12:45 |
| Financial_Report.xlsx | 26205 | 2016-05-13 16:12:45 |
| npk-20160403.xml | 408179 | 2016-05-13 16:12:45 |
| npk-20160403.xsd | 14613 | 2016-05-13 16:12:45 |
| npk-20160403x10q.htm | 868742 | 2016-05-13 16:12:45 |
| npk-20160403xex31_1.htm | 15337 | 2016-05-13 16:12:45 |
| npk-20160403xex31_2.htm | 15618 | 2016-05-13 16:12:45 |
| npk-20160403xex32_1.htm | 8704 | 2016-05-13 16:12:45 |
| npk-20160403xex32_2.htm | 8835 | 2016-05-13 16:12:45 |
| npk-20160403_cal.xml | 36716 | 2016-05-13 16:12:45 |
| npk-20160403_def.xml | 27269 | 2016-05-13 16:12:45 |
| npk-20160403_lab.xml | 128203 | 2016-05-13 16:12:45 |
| npk-20160403_pre.xml | 102602 | 2016-05-13 16:12:45 |
| R1.htm | 20398 | 2016-05-13 16:12:45 |
| R10.htm | 9466 | 2016-05-13 16:12:45 |
| R11.htm | 69695 | 2016-05-13 16:12:45 |
| R12.htm | 5896 | 2016-05-13 16:12:45 |
| R13.htm | 6177 | 2016-05-13 16:12:45 |
| R14.htm | 12701 | 2016-05-13 16:12:45 |
| R15.htm | 96800 | 2016-05-13 16:12:45 |
| R16.htm | 62454 | 2016-05-13 16:12:45 |
| R17.htm | 27205 | 2016-05-13 16:12:45 |
| R18.htm | 28284 | 2016-05-13 16:12:45 |
| R19.htm | 17329 | 2016-05-13 16:12:45 |
| R2.htm | 83242 | 2016-05-13 16:12:45 |
| R20.htm | 8348 | 2016-05-13 16:12:45 |
| R3.htm | 9042 | 2016-05-13 16:12:45 |
| R4.htm | 42240 | 2016-05-13 16:12:45 |
| R5.htm | 64227 | 2016-05-13 16:12:45 |
| R6.htm | 7150 | 2016-05-13 16:12:45 |
| R7.htm | 5406 | 2016-05-13 16:12:45 |
| R8.htm | 6374 | 2016-05-13 16:12:45 |
| R9.htm | 100625 | 2016-05-13 16:12:45 |
| report.css | 2767 | 2016-05-13 16:12:45 |
| Show.js | 1410 | 2016-05-13 16:12:45 |