Note B - Adoption of New Accounting Pronouncements - Impact of New Standard on Condensed Consolidated Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Sep. 23, 2018	Sep. 24, 2017		Sep. 23, 2018		Sep. 24, 2017		Mar. 25, 2018
Deferred income taxes	$ 406			$ 406				$ 0
Total assets	86,381			86,381				80,091
Accrued expenses and other current liabilities	11,040			11,040				11,248
Deferred franchise fees	559			559				193
Total current liabilities	16,253			16,253				18,006
Deferred income taxes								302
Deferred franchise fees	3,044			3,044				238
Total liabilities	165,704			165,704				164,659
(Accumulated deficit)	(63,000)			(63,000)				(68,181)
Stockholders’ (deficit) before treasury stock	(2,020)			(2,020)				(7,265)
Total stockholders’ (deficit)	(79,323)			(79,323)				(84,568)
Total liabilities and stockholders’ (deficit)	86,381			86,381				$ 80,091
Revenues	29,330	$ 31,471	[1]	59,498	[1]	$ 62,274	[1]
General and administrative expenses	3,438	3,359		7,323		7,030
Advertising fund expense (Note B)	772	0		1,267
Total costs and expenses	20,850	22,737		41,931		45,090
Income from operations	8,480	8,734		17,567		17,184
Income before provision for income taxes	6,463	5,127		12,982		9,970
Provision for income taxes	1,979	2,007		3,703		3,928
Net income	4,484	3,120		9,279		6,042
Accounts payable, accrued expenses and other current liabilities				(2,015)		(431)
Deferred franchise fees				437
Net cash provided by operating activities				10,003		5,401
Net cash provided by investing activities				1,096		(357)
Net cash (used in) financing activities				(2,284)		(282)
Net increase in cash				8,815		4,762
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Franchise Fees Adjustments [Member]
Deferred income taxes	(731)			(731)
Total assets	(731)			(731)
Accrued expenses and other current liabilities	(112)			(112)
Deferred franchise fees	(378)			(378)
Total current liabilities	(490)			(490)
Deferred income taxes
Deferred franchise fees	(2,219)			(2,219)
Total liabilities	(2,709)			(2,709)
(Accumulated deficit)	1,978			1,978
Stockholders’ (deficit) before treasury stock	1,978			1,978
Total stockholders’ (deficit)	1,978			1,978
Total liabilities and stockholders’ (deficit)	(731)			(731)
Revenues	(66)			(138)
General and administrative expenses	(2)			(98)
Advertising fund expense (Note B)
Total costs and expenses	(2)			(98)
Income from operations	(64)			(40)
Income before provision for income taxes	(64)			(40)
Provision for income taxes	(20)			(14)
Net income	(44)			(26)
Accounts payable, accrued expenses and other current liabilities				(112)
Deferred franchise fees				138
Net cash provided by operating activities
Net cash provided by investing activities
Net cash (used in) financing activities
Net increase in cash
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Balance Sheet Reclassification Adjustments [Member]
Deferred income taxes	325			325
Total assets	325			325
Accrued expenses and other current liabilities
Deferred franchise fees	14			14
Total current liabilities	14			14
Deferred income taxes	325			325
Deferred franchise fees	(14)			(14)
Total liabilities	325			325
(Accumulated deficit)
Stockholders’ (deficit) before treasury stock
Total stockholders’ (deficit)
Total liabilities and stockholders’ (deficit)	325			325
Revenues	(772)			(1,267)
General and administrative expenses
Advertising fund expense (Note B)	(772)			(1,267)
Total costs and expenses	(772)			(1,267)
Income from operations
Income before provision for income taxes
Provision for income taxes
Net income
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Advertising Fund Adjustments [Member]
Net income
Accounts payable, accrued expenses and other current liabilities
Deferred franchise fees
Net cash provided by operating activities
Net cash provided by investing activities
Net cash (used in) financing activities
Net increase in cash
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Deferred income taxes
Total assets	85,975			85,975
Accrued expenses and other current liabilities	10,928			10,928
Deferred franchise fees	195			195
Total current liabilities	15,777			15,777
Deferred income taxes	325			325
Deferred franchise fees	811			811
Total liabilities	163,320			163,320
(Accumulated deficit)	(61,022)			(61,022)
Stockholders’ (deficit) before treasury stock	(42)			(42)
Total stockholders’ (deficit)	(77,345)			(77,345)
Total liabilities and stockholders’ (deficit)	85,975			85,975
Revenues	28,492			58,093
General and administrative expenses	3,436			7,225
Advertising fund expense (Note B)
Total costs and expenses	20,076			40,566
Income from operations	8,416			17,527
Income before provision for income taxes	6,399			12,942
Provision for income taxes	1,959			3,689
Net income	4,440			9,253
Accounts payable, accrued expenses and other current liabilities				(2,127)
Deferred franchise fees				575
Net cash provided by operating activities				10,003
Net cash provided by investing activities				1,096
Net cash (used in) financing activities				(2,284)
Net increase in cash				8,815
Franchise Fees and Royalties [Member]
Revenues	1,239	1,315	[1]	2,343	[1]	2,487	[1]
Franchise Fees and Royalties [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Franchise Fees Adjustments [Member]
Revenues	(66)			(138)
Franchise Fees and Royalties [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Balance Sheet Reclassification Adjustments [Member]
Revenues
Franchise Fees and Royalties [Member] | Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenues	1,173			2,205
Advertising Fund Revenue [Member]
Revenues	772		[1]	1,267	[1]		[1]
Advertising Fund Revenue [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Franchise Fees Adjustments [Member]
Revenues
Advertising Fund Revenue [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Balance Sheet Reclassification Adjustments [Member]
Revenues	(772)			(1,267)
Advertising Fund Revenue [Member] | Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenues

[1] As disclosed in Note B, prior period amounts have not been adjusted under the modified retrospective method of adoption of ASC 606.