XML 52 R45.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Note 4 - Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Mar. 30, 2014 | Mar. 31, 2013 | Mar. 25, 2012
Marketable Securities Disclosure [Abstract] |  |  |
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax | $ (180) | $ (168) | $ 16

X
- Details
Name: | nath_MarketableSecuritiesDisclosureTextBlockAbstract
Namespace Prefix: | nath_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration