Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001437749-22-012342-index-headers.html | 2022-05-13 16:00:58 | |
| 0001437749-22-012342-index.html | 2022-05-13 16:00:58 | |
| 0001437749-22-012342.txt | 2022-05-13 16:00:58 | |
 0001437749-22-012342-xbrl.zip | 84765 | 2022-05-13 16:00:58 |
| ex_357249.htm | 10565 | 2022-05-13 16:00:58 |
| ex_357250.htm | 10750 | 2022-05-13 16:00:58 |
| ex_357251.htm | 5206 | 2022-05-13 16:00:58 |
| ex_357252.htm | 5219 | 2022-05-13 16:00:58 |
| FilingSummary.xml | 20850 | 2022-05-13 16:00:58 |
| Financial_Report.xlsx | 38664 | 2022-05-13 16:00:58 |
| MetaLinks.json | 362932 | 2022-05-13 16:00:58 |
| npk-20220403.xsd | 26732 | 2022-05-13 16:00:58 |
| npk-20220403_cal.xml | 35597 | 2022-05-13 16:00:58 |
| npk-20220403_def.xml | 188916 | 2022-05-13 16:00:58 |
| npk-20220403_lab.xml | 176361 | 2022-05-13 16:00:58 |
| npk-20220403_pre.xml | 210519 | 2022-05-13 16:00:58 |
| npk20220411_10q.htm | 534649 | 2022-05-13 16:00:58 |
| npk20220411_10q_htm.xml | 335527 | 2022-05-13 16:00:58 |
| R1.htm | 52594 | 2022-05-13 16:00:58 |
| R10.htm | 14807 | 2022-05-13 16:00:58 |
| R11.htm | 6026 | 2022-05-13 16:00:58 |
| R12.htm | 43934 | 2022-05-13 16:00:58 |
| R13.htm | 7811 | 2022-05-13 16:00:58 |
| R14.htm | 32656 | 2022-05-13 16:00:58 |
| R15.htm | 5271 | 2022-05-13 16:00:58 |
| R16.htm | 31273 | 2022-05-13 16:00:58 |
| R17.htm | 7539 | 2022-05-13 16:00:58 |
| R18.htm | 15572 | 2022-05-13 16:00:58 |
| R19.htm | 39961 | 2022-05-13 16:00:58 |
| R2.htm | 118922 | 2022-05-13 16:00:58 |
| R20.htm | 27310 | 2022-05-13 16:00:58 |
| R21.htm | 30107 | 2022-05-13 16:00:58 |
| R22.htm | 16817 | 2022-05-13 16:00:58 |
| R23.htm | 7986 | 2022-05-13 16:00:58 |
| R24.htm | 46594 | 2022-05-13 16:00:58 |
| R25.htm | 22277 | 2022-05-13 16:00:58 |
| R26.htm | 17145 | 2022-05-13 16:00:58 |
| R27.htm | 7428 | 2022-05-13 16:00:58 |
| R28.htm | 10261 | 2022-05-13 16:00:58 |
| R29.htm | 7060 | 2022-05-13 16:00:58 |
| R3.htm | 7109 | 2022-05-13 16:00:58 |
| R30.htm | 18890 | 2022-05-13 16:00:58 |
| R31.htm | 15039 | 2022-05-13 16:00:58 |
| R32.htm | 6791 | 2022-05-13 16:00:58 |
| R4.htm | 74299 | 2022-05-13 16:00:58 |
| R5.htm | 71026 | 2022-05-13 16:00:58 |
| R6.htm | 36324 | 2022-05-13 16:00:58 |
| R7.htm | 4287 | 2022-05-13 16:00:58 |
| R8.htm | 5863 | 2022-05-13 16:00:58 |
| R9.htm | 5811 | 2022-05-13 16:00:58 |
| report.css | 2767 | 2022-05-13 16:00:58 |
| Show.js | 1085 | 2022-05-13 16:00:58 |