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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The termination fee in cash that the company would be required to pay if certain termination conditions are met.

No definition available.

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

The amount of retention bonus required to be paid if certain conditions are met.

No definition available.

Name:	nath_MergerRetentionBonus
Namespace Prefix:	nath_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount per share that owners of the company's stock will receive as part of the merger consideration.

No definition available.

Name:	nath_PerShareMergerConsideration
Namespace Prefix:	nath_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

The number of shares converted during a merger.

No definition available.

Name:	nath_PerShareMergerConsiderationShares
Namespace Prefix:	nath_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Face amount or stated value per share of common stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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