Stockholders' Equity (Details) - USD ($)		3 Months Ended		9 Months Ended
		Dec. 26, 2015	Dec. 27, 2014	Dec. 26, 2015	Dec. 27, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares				8,859,199
Beginning balance				$ 320,154,000
Stock option exercises, amount				1,702,000
Stock-based compensation				1,512,000
Net income		$ 8,098,000	$ 6,638,000	21,553,000	$ 17,864,000
Other comprehensive loss	[1]			$ (742,000)
Ending balance, common stock, shares		8,912,133		8,912,133
Ending balance		$ 344,179,000		$ 344,179,000
Pre-tax unrealized loss on available-for-sale investments				$ (1,161,000)
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares				8,859,199
Beginning balance				$ 89,000
Stock option exercises, shares				52,934
Stock option exercises, amount				$ 0
Stock-based compensation				0
Net income				0
Other comprehensive loss				$ 0
Ending balance, common stock, shares		8,912,133		8,912,133
Ending balance		$ 89,000		$ 89,000
Additional paid-in capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				237,916,000
Stock option exercises, amount				1,702,000
Stock-based compensation				1,512,000
Net income				0
Other comprehensive loss				0
Ending balance		241,130,000		241,130,000
Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				81,645,000
Stock option exercises, amount				0
Stock-based compensation				0
Net income				21,553,000
Other comprehensive loss				0
Ending balance		103,198,000		103,198,000
Accumulated other comprehensive income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				504,000
Stock option exercises, amount				0
Stock-based compensation				0
Net income				0
Other comprehensive loss	[1]			(742,000)
Ending balance		$ (238,000)		$ (238,000)

[1] Other comprehensive income is comprised of unrealized gains and losses on available-for-sale investments. Unrealized losses before tax effect on available-for-sale securities were $1.2 million for the nine months ended December 26, 2015.