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|---|---|---|
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| 0000080172-17-000049-index.html | 2017-11-13 16:09:59 | |
| 0000080172-17-000049.txt | 2017-11-13 16:09:59 | |
 0000080172-17-000049-xbrl.zip | 59782 | 2017-11-13 16:09:59 |
| FilingSummary.xml | 17172 | 2017-11-13 16:09:59 |
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| npk-20171001xex31_1.htm | 15366 | 2017-11-13 16:09:59 |
| npk-20171001xex31_2.htm | 15647 | 2017-11-13 16:09:59 |
| npk-20171001xex32_1.htm | 8872 | 2017-11-13 16:09:59 |
| npk-20171001xex32_2.htm | 9069 | 2017-11-13 16:09:59 |
| npk-20171001_cal.xml | 52474 | 2017-11-13 16:09:59 |
| npk-20171001_def.xml | 54229 | 2017-11-13 16:09:59 |
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| R9.htm | 157407 | 2017-11-13 16:09:59 |
| report.css | 2767 | 2017-11-13 16:09:59 |
| Show.js | 1410 | 2017-11-13 16:09:59 |