Stockholders' Equity (Details) - USD ($)		3 Months Ended
		Jul. 02, 2016	Jun. 27, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares		8,927,989
Beginning balance		$ 353,226,000
Stock option exercises, amount		(341,000)
Stock-based compensation		370,000
Net income		5,443,000	$ 5,385,000
Other comprehensive loss	[1]	$ (55,000)
Ending balance, common stock, shares		8,970,314
Ending balance		$ 358,643,000
Pre-tax unrealized loss on available-for-sale investments		$ (112,000)
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares		8,927,989
Beginning balance		$ 89,000
Stock option exercises, shares		42,325
Stock option exercises, amount		$ 1,000
Stock-based compensation		0
Net income		0
Other comprehensive loss		$ 0
Ending balance, common stock, shares		8,970,314
Ending balance		$ 90,000
Additional paid-in capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		241,662,000
Stock option exercises, amount		(342,000)
Stock-based compensation		370,000
Net income		0
Other comprehensive loss		0
Ending balance		241,690,000
Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		110,186,000
Stock option exercises, amount		0
Stock-based compensation		0
Net income		5,443,000
Other comprehensive loss		0
Ending balance		115,629,000
Accumulated other comprehensive income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		1,289,000
Stock option exercises, amount		0
Stock-based compensation		0
Net income		0
Other comprehensive loss	[1]	(55,000)
Ending balance		$ 1,234,000

[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 $112,000 for the three months ended July 2, 2016.