Consolidated Statement of Shareholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Jan. 03, 2015	$ 256,907	$ 528	$ 0	$ 256,413	$ (34)
Balance (in shares) at Jan. 03, 2015	52,798,000	52,798,000
Net income	28,799	0	0	28,799	0
Other comprehensive income:
Unrealized gain on available-for-sale marketable debt securities, net of tax	72	0	0	0	72
Exercise of common stock options	1,353	1	1,352	0	0
Exercise of common stock options (in shares)		118,000
Tax effect from stock-based compensation	816	0	816	0	0
Stock-based compensation (in shares)		33,000
Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures	2,782	0	2,782	0	0
Repurchases of common stock	(20,475)	(6)	(4,950)	(15,519)	0
Repurchases of common stock (in shares)		(650,000)
Balance at Apr. 04, 2015	$ 270,254	$ 523	$ 0	$ 269,693	$ 38
Balance (in shares) at Apr. 04, 2015	52,299,000	52,299,000