Income Taxes - Reconciliation. Provision and Deferred Taxes (Details) - USD ($)	3 Months Ended								12 Months Ended
	Mar. 26, 2017	Dec. 25, 2016	Sep. 25, 2016	Jun. 26, 2016	Mar. 27, 2016	Dec. 27, 2015	Sep. 27, 2015	Jun. 28, 2015	Mar. 26, 2017	Mar. 27, 2016	Mar. 29, 2015
Effective income tax rate reconciliation
Statutory federal rate (as a percent)									34.00%	34.00%	34.20%
State taxes, net of federal benefit (as a percent)									4.60%	4.50%	4.10%
Non-deductible expenses (as a percent)									5.40%	2.10%	0.90%
Other (as a percent)									(2.10%)	(0.80%)
Effective rate (as a percent)									41.90%	39.80%	39.20%
Federal
Current									$ 1,083,600	$ 2,350,000	$ 3,035,400
Deferred									(69,100)	763,100	1,964,800
State
Current									53,100	345,100	398,500
Deferred									(26,400)	73,600	178,100
Provision for income taxes	$ (895,000)	$ 843,100	$ 1,034,700	$ 58,400	$ (1,205,800)	$ 1,768,800	$ 1,850,900	$ 1,117,900	1,041,200	3,531,800	$ 5,576,800
Net deferred tax assets (liabilities)
Deferred compensation	142,600				357,500				142,600	357,500
Accrued vacation	566,900				534,200				566,900	534,200
Deferred rent	208,900				459,100				208,900	459,100
Allowance for doubtful accounts	259,300				266,300				259,300	266,300
Inventory reserves	2,338,800				2,264,500				2,338,800	2,264,500
Sales tax reserves	366,000				366,500				366,000	366,500
Other assets	800,000				475,200				800,000	475,200
Tax contingency reserve	215,800				247,600				215,800	247,600
Depreciation and amortization	(3,659,100)				(3,646,200)				(3,659,100)	(3,646,200)
Other liabilities	(461,600)				(374,100)				(461,600)	(374,100)
Accrued compensation	(286,300)				(577,600)				(286,300)	(577,600)
Prepaid expenses	(878,100)				(752,400)				(878,100)	(752,400)
Net Deferred Tax Liability	(386,800)				(379,400)				(386,800)	(379,400)
Valuation allowance	$ 0				$ 0				$ 0	$ 0