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

Represents the percentage ownership of the debt instrument that enables the holders to declare the debt instrument due and payable by providing notice to the Company, in the event of default.

+ References

No definition available.

+ Details

Name:	nath_DebtInstrumentEventOfDefaultPercentageOwnershipEnablingTheDeclarationOfDueAndPayable
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 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: 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=64930785&loc=d3e28551-108399

+ 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 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=75038535&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, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

+ Details

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

- Definition

Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

+ Details

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

- Definition

Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

+ Details

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

- Details

Name:	us-gaap_DividendsAxis=nath_SpecialCashDividendMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=nath_InTheEventOfCertainEquityOfferingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=nath_InTheEventOfChangeOfControlOfferMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=nath_InTheEventTheCompanySellsCertainAssetsAndFailsToUseTheProceedsAsRequiredMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=nath_OptionToRedeemNotesAtRedemptionPriceEqualToThePercentageOfPrincipalAmountPlusTheApplicablePremiumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=nath_ApplicablePremiumIfPercentageOfPrincipalAmountIsGreaterThanTreasuryRateBasisSpreadMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=nath_ApplicablePremiumIfTreasuryRateBasisSpreadIsGreaterThanPercentageOfPrincipalAmountMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=nath_TreasuryRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=nath_OptionToRedeemAtRedemptionPriceEqualToPercentageOfPrincipalAmountMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note L - Long-term Debt (Details Textual) - USD ($) $ in Thousands				12 Months Ended
	Mar. 15, 2017	Sep. 15, 2016	Mar. 10, 2015	Mar. 26, 2017	Mar. 27, 2016	Mar. 29, 2015
Debt Instrument, Interest Rate, Stated Percentage				10.00%	10.00%
Interest Paid				$ 13,500	$ 13,688
Special Cash Dividend [Member]
Dividends, Cash			$ 116,100
Secured Debt [Member]
Debt Instrument, Face Amount			$ 135,000
Debt Instrument, Interest Rate, Stated Percentage			10.00%
Debt Issuance Costs, Gross			$ 5,985
Debt Instrument, Term			5 years
Interest Paid	$ 6,750	$ 6,750
Debt Instrument, Fixed Charge Coverage Ratio			2
Debt Instrument, Priority Secured Leverage Ratio			0.4
Debt Instrument Secured Leverage Ratio			3.75
Debt Instrument, Event of Default, Percentage Ownership Enabling the Declaration of Due and Payable			25.00%
Secured Debt [Member] \| In The Event of Certain Equity Offerings [Member]
Debt Instrument, Redemption Price, Percentage			110.00%
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] \| 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] \| 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 at Redemption Price Equal to Percentage of Principal Amount [Member] \| In The Event of Certain Equity Offerings [Member] \| Maximum [Member]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed			35.00%