Stockholders' Equity (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	Jul. 22, 2013	Dec. 27, 2014	Dec. 28, 2013	Dec. 27, 2014		Dec. 28, 2013
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares				8,844,824
Beginning balance				$ 290,433,000
Stock option exercises, shares	1,867,370
Stock option exercises, amount				4,099,000
Stock-based compensation				1,408,000
Net income		6,638,000	5,892,000	17,864,000		12,028,000
Other comprehensive loss				(34,000)	[1]
Ending balance, common stock, shares		8,857,449		8,857,449
Ending balance		313,770,000		313,770,000
Pre-tax unrealized loss on available-for-sale investments				(53,000)
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares				8,844,824
Beginning balance				88,000
Stock option exercises, shares				12,625
Stock option exercises, amount				1,000
Stock-based compensation				0
Net income				0
Other comprehensive loss				0
Ending balance, common stock, shares		8,857,449		8,857,449
Ending balance		89,000		89,000
Additional paid-in capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				232,081,000
Stock option exercises, amount				4,098,000
Stock-based compensation				1,408,000
Net income				0
Other comprehensive loss				0
Ending balance		237,587,000		237,587,000
Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				57,828,000
Stock option exercises, amount				0
Stock-based compensation				0
Net income				17,864,000
Other comprehensive loss				0
Ending balance		75,692,000		75,692,000
Accumulated other comprehensive income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				436,000
Stock option exercises, amount				0
Stock-based compensation				0
Net income				0
Other comprehensive loss				(34,000)	[1]
Ending balance		$ 402,000		$ 402,000

[1] Other comprehensive income is comprised of unrealized gains and losses on available-for-sale investments. Unrealized losses before tax on available-for-sale investments were $53,000 for the nine months ended December 27, 2014.