Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012
Cash flows from operating activities:
Net income	$ 53,656	$ 65,599
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	22,199	14,411
Stock-based compensation	3,058	9,570
Net (gain) loss on disposals and impairments of assets	(10)	86
Excess tax benefits from stock-based compensation	(3,088)	(4,947)
Deferred income taxes	4,288	(737)
Changes in operating assets and liabilities, net of effect of acquisition:
Accounts receivable	1,717	(1,237)
Inventories	(5,069)	(4,146)
Income taxes	7,114	10,715
Prepaid expenses and other assets	(5,144)	(6,031)
Accounts payable	11,029	10,565
Customer prepayments	97	1,882
Accrued compensation and benefits	(5,607)	(6,588)
Other taxes and withholding	1,504	2,291
Warranty liabilities	(1,218)	(1,247)
Other accruals and liabilities	5,556	7,450
Net cash provided by operating activities	90,082	97,636
Cash flows from investing activities:
Purchases of property and equipment	(57,820)	(36,816)
Proceeds from maturities of marketable debt securities	31,973	10,103
Investments in marketable debt securities	(26,041)	(63,240)
Acquisition of business	(15,500)	0
Investment in non-marketable equity securities	(3,000)	0
Proceeds from sales of property and equipment	117	42
Net cash used in investing activities	(70,271)	(89,911)
Cash flows from financing activities:
Repurchases of common stock	(32,054)	(24,071)
Proceeds from issuance of common stock	7,108	3,279
Net (decrease) increase in short-term borrowings	(4,567)	2,323
Excess tax benefits from stock-based compensation	3,088	4,947
Debt issuance costs	0	(50)
Net cash used in financing activities	(26,425)	(13,572)
Net decrease in cash and cash equivalents	(6,614)	(5,847)
Cash and cash equivalents, at beginning of period	87,915	116,255
Cash and cash equivalents, at end of period	$ 81,301	$ 110,408