XML 36 R25.htm IDEA: XBRL DOCUMENT v3.25.3

Note B - Revenues 1 (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 28, 2025	Sep. 29, 2024	Sep. 28, 2025	Sep. 29, 2024	Dec. 31, 2024
Defense [Member]
Contract with Customer, Liability, Current	$ 10,606,000		$ 10,606,000		$ 7,345,000
Contract with Customer, Liability, Revenue Recognized	7,110,000
Contract with Customer, Performance Obligation Satisfied in Previous Period	0	$ 0	0	$ 0
Revenue, Remaining Performance Obligation, Amount	$ 1,416,082,000		$ 1,416,082,000		$ 1,085,612,000
Minimum [Member]
Revenue Contract Period (Month)			3 months
Maximum [Member]
Revenue Contract Period (Month)			42 months

X

- Definition

Represents the revenue contract period.

+ References

No definition available.

+ Details

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Namespace Prefix:	npk_
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Balance Type:	na
Period Type:	duration

X

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479837/606-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479837/606-10-45-2

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Balance Type:	credit
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X

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

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X

- Definition

Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12A

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X

- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

+ Details

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Period Type:

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