Parent Directory| Name | Size | Last Modified |
|---|---|---|
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| 0000080172-18-000046-index.html | 2018-11-09 16:01:50 | |
| 0000080172-18-000046.txt | 2018-11-09 16:01:50 | |
 0000080172-18-000046-xbrl.zip | 67151 | 2018-11-09 16:01:50 |
| FilingSummary.xml | 20191 | 2018-11-09 16:01:50 |
| Financial_Report.xlsx | 38255 | 2018-11-09 16:01:50 |
| npk-20180930.xml | 736047 | 2018-11-09 16:01:50 |
| npk-20180930.xsd | 20768 | 2018-11-09 16:01:50 |
| npk-20180930x10q.htm | 844181 | 2018-11-09 16:01:50 |
| npk-20180930xex31_1.htm | 15226 | 2018-11-09 16:01:50 |
| npk-20180930xex31_2.htm | 15644 | 2018-11-09 16:01:50 |
| npk-20180930xex32_1.htm | 8872 | 2018-11-09 16:01:50 |
| npk-20180930xex32_2.htm | 9069 | 2018-11-09 16:01:50 |
| npk-20180930_cal.xml | 52738 | 2018-11-09 16:01:50 |
| npk-20180930_def.xml | 74926 | 2018-11-09 16:01:50 |
| npk-20180930_lab.xml | 185203 | 2018-11-09 16:01:50 |
| npk-20180930_pre.xml | 175808 | 2018-11-09 16:01:50 |
| R1.htm | 25623 | 2018-11-09 16:01:50 |
| R10.htm | 157339 | 2018-11-09 16:01:50 |
| R11.htm | 7752 | 2018-11-09 16:01:50 |
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| R18.htm | 157391 | 2018-11-09 16:01:50 |
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| R2.htm | 93065 | 2018-11-09 16:01:50 |
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| R8.htm | 16080 | 2018-11-09 16:01:50 |
| R9.htm | 5008 | 2018-11-09 16:01:50 |
| report.css | 2767 | 2018-11-09 16:01:50 |
| Show.js | 1085 | 2018-11-09 16:01:50 |