Consolidated Statement of Shareholders' Equity - 9 months ended Oct. 01, 2016 - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance (in shares) at Jan. 02, 2016	49,402,000	49,402,000
Balance at Jan. 02, 2016	$ 222,339	$ 494	$ 0	$ 221,859	$ (14)
Net income	40,130	0	0	40,130	0
Other comprehensive income:
Unrealized gain on available-for-sale marketable debt securities, net of tax	14	$ 0	0	0	14
Exercise of common stock options (in shares)		173,000
Exercise of common stock options	1,949	$ 1	1,948	0	0
Tax effect from stock-based compensation	(782)	$ 0	(782)	0	0
Stock-based compensation (in shares)		11,000
Stock-based compensation	9,272	$ 0	9,272	0	0
Repurchases of common stock (in shares)		(4,645,000)
Repurchases of common stock	$ (96,410)	$ (46)	(10,438)	(85,926)	0
Balance (in shares) at Oct. 01, 2016	44,491,000	44,941,000
Balance at Oct. 01, 2016	$ 176,512	$ 449	$ 0	$ 176,063	$ 0