Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016
Cash flows from operating activities:
Net income	$ 23,683	$ 14,385
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	31,177	27,960
Stock-based compensation	7,876	7,606
Net loss on disposals and impairments of assets	2	7
Excess tax benefits from stock-based compensation	0	(472)
Deferred income taxes	4,974	985
Changes in operating assets and liabilities:
Accounts receivable	(4,781)	5,489
Inventories	5,170	12,904
Income taxes	(14,532)	15,324
Prepaid expenses and other assets	2,110	(6,838)
Accounts payable	11,858	(15,282)
Customer prepayments	19,518	(26,885)
Accrued compensation and benefits	9,834	9,249
Other taxes and withholding	(6,032)	1,654
Other accruals and liabilities	(2,050)	1,034
Net cash provided by operating activities	88,807	47,120
Cash flows from investing activities:
Purchases of property and equipment	(27,132)	(23,764)
Proceeds from marketable debt securities	0	15,090
Proceeds from sales of property and equipment	0	67
Decrease in restricted cash	3,150	0
Net cash used in investing activities	(23,982)	(8,607)
Cash flows from financing activities:
Repurchases of common stock	(80,094)	(71,366)
Net increase in short-term borrowings	3,098	12,574
Proceeds from issuance of common stock	2,654	1,623
Excess tax benefits from stock-based compensation	0	472
Debt issuance costs	(10)	(409)
Net cash used in financing activities	(74,352)	(57,106)
Net decrease in cash and cash equivalents	(9,527)	(18,593)
Cash and cash equivalents, at beginning of period	11,609	20,994
Cash and cash equivalents, at end of period	$ 2,082	$ 2,401