Note H - Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 28, 2025	Mar. 31, 2025	Mar. 30, 2025
Income taxes	$ 0		$ 493
Real estate taxes	84		80
Insurance	91		379
Marketing	145		798
Other	363		298
Total prepaid expenses and other current assets	$ 683	$ 2,048	$ 2,048

Represents current prepaid marketing expense.

No definition available.

Name:	nath_PrepaidMarketingExpenseCurrent
Namespace Prefix:	nath_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents current prepaid real estate taxes expense.

+ References

No definition available.

+ Details

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Namespace Prefix:	nath_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of current assets classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
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-Publisher FASB
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+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-02(9))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
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-URI https://asc.fasb.org/1943274/2147482955/340-10-05-5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of asset related to consideration paid in advance for income and other taxes that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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-URI https://asc.fasb.org/1943274/2147482955/340-10-05-5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant