Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2013	Mar. 31, 2012
Cash flows from operating activities:
Net income	$ 23,471	$ 22,417
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,661	4,245
Stock-based compensation	432	6,964
Net loss on disposals and impairments of assets	27	4
Excess tax benefits from stock-based compensation	(2,401)	(2,372)
Deferred income taxes	585	(2,610)
Changes in operating assets and liabilities:
Accounts receivable	2,454	1,390
Inventories	5,269	(33)
Income taxes	7,534	10,388
Prepaid expenses and other assets	(889)	186
Accounts payable	12,955	6,591
Customer prepayments	2,302	6,348
Accrued compensation and benefits	(9,165)	(12,449)
Other taxes and withholding	(1,443)	1,160
Warranty liabilities	(239)	569
Other accruals and liabilities	(2,531)	1,720
Net cash provided by operating activities	45,022	44,518
Cash flows from investing activities:
Acquisition of business	(15,500)	0
Purchases of property and equipment	(14,309)	(9,281)
Investments in marketable debt securities	(12,883)	0
Proceeds from maturities of marketable debt securities	5,898	0
Investment in non-marketable equity securities	(1,500)	0
Proceeds from sales of property and equipment	3	9
Net cash used in investing activities	(38,291)	(9,272)
Cash flows from financing activities:
Repurchases of common stock	(10,144)	(1,214)
Net decrease in short-term borrowings	(4,370)	(3,371)
Excess tax benefits from stock-based compensation	2,401	2,372
Proceeds from issuance of common stock	2,282	1,655
Net cash used in by financing activities	(9,831)	(558)
Net (decrease) increase in cash and cash equivalents	(3,100)	34,688
Cash and cash equivalents, at beginning of period	87,915	116,255
Cash and cash equivalents, at end of period	$ 84,815	$ 150,943