Note K - Long-term Debt (Details Textual) (USD $)	0 Months Ended	12 Months Ended
Mar. 10, 2015	Mar. 29, 2015
Debt Instrument, Interest Rate, Stated Percentage		10.00%
Payments of Ordinary Dividends, Common Stock	$ 116,100,000us-gaap_PaymentsOfDividendsCommonStock	$ 115,110,000us-gaap_PaymentsOfDividendsCommonStock
Long-term Debt, Fair Value		141,835,000us-gaap_LongTermDebtFairValue
Secured Debt [Member] \| Maximum [Member] \| Option to Redeem at Redemption Price Equal to Percentage of Principal Amount [Member]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed	35.00%
Secured Debt [Member] \| Option to Redeem Notes at Redemption Price Equal to the Percentage of Principal Amount plus the Applicable Premium [Member] \| Applicable Premium if Percentage of Principal Amount is Greater than Treasury Rate Basis Spread [Member]
Debt Instrument, Applicable Premium, Percentage of Principal Amount	1.00%
Secured Debt [Member] \| Option to Redeem Notes at Redemption Price Equal to the Percentage of Principal Amount plus the Applicable Premium [Member] \| Applicable Premium if Treasury Rate Basis Spread is Greater than Percentage of Principal Amount [Member] \| Treasury Rate [Member]
Debt Instrument, Applicable Premium, Treasury Rate Basis Spread	0.50%
Secured Debt [Member] \| Option to Redeem Notes at Redemption Price Equal to the Percentage of Principal Amount plus the Applicable Premium [Member]
Debt Instrument, Redemption Price, Percentage	100.00%
Secured Debt [Member] \| In the Event of Chang of Control Offer [Member]
Debt Instrument, Redemption Price, Percentage	101.00%
Secured Debt [Member] \| In the Event the Company Sells Certain Assets and Fails to Use the Proceeds as Required [Member]
Debt Instrument, Redemption Price, Percentage	100.00%
Secured Debt [Member]
Debt Instrument, Face Amount	135,000,000
Debt Instrument, Interest Rate, Stated Percentage	10.00%
Debt Issuance Cost	5,926,000
Debt Instrument, Term	5 years
Debt Instrument, Fixed Charge Coverage Ratio	2
Debt Instrument, Priority Secured Leverage Ratio	0.4
Debt Instrument Secured Leverage Ratio	3.75
Debt Instrument, Redemption Price, Percentage	110.00%
Long-term Debt, Fair Value		$ 141,835,000

Applicable premium if using the percentage of principal amount.

No definition available.

Name:	nath_DebtInstrumentApplicablePremiumPercentageOfPrincipalAmount
Namespace Prefix:	nath_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Applicable premium if treasury rate basis spread is used.

+ References

No definition available.

+ Details

Name:	nath_DebtInstrumentApplicablePremiumTreasuryRateBasisSpread
Namespace Prefix:	nath_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Ration of consolidated cash flows to the fixed charges for the relevant period.

+ References

No definition available.

+ Details

Name:	nath_DebtInstrumentFixedChargeCoverageRatio
Namespace Prefix:	nath_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

The ratio of consolidated net debt outstanding secured by a priority lien to consolidated cash flow.

+ References

No definition available.

+ Details

Name:	nath_DebtInstrumentPrioritySecuredLeverageRatio
Namespace Prefix:	nath_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio of consolidated Net debt outstanding that is secured by a lien on any property the company owns to consolidated cash flows.

+ References

No definition available.

+ Details

Name:	nath_DebtInstrumentSecuredLeverageRatio
Namespace Prefix:	nath_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph e

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

+ Details

Name:	us-gaap_DebtIssuanceCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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