Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Jan. 01, 2011	Jan. 02, 2010
Cash flows from operating activities:
Net income	$ 60,478	$ 31,568	$ 35,552
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	13,543	14,626	19,054
Stock-based compensation	4,971	3,962	3,236
Net disposals and impairments of assets	98	251	683
Excess tax benefits from stock-based compensation	(2,190)	(1,358)	0
Deferred income taxes	2,839	2,352	(18,209)
Accounts receivable	(3,935)	718	(3,618)
Inventories	(5,204)	(4,001)	3,029
Income taxes	4,445	6,647	22,007
Prepaid expenses and other assets	(1,976)	1,579	(1,776)
Accounts payable	6,913	3,995	2,545
Customer prepayments	585	1,707	(243)
Accrued compensation and benefits	5,167	11,471	943
Other taxes and withholding	1,944	53	1,604
Warranty liabilities	566	(1,398)	(906)
Other accruals and liabilities	2,802	(765)	(725)
Net cash provided by operating activities	91,046	71,407	63,176
Cash flows from investing activities:
Investments in marketable debt securities	(40,021)	0	0
Proceeds from maturities of marketable debt securities	10,000	0	0
Purchases of property and equipment	(23,527)	(7,349)	(2,459)
Increase in restricted cash	(2,650)	0	0
Proceeds from sales of property and equipment	11	10	15
Net cash used in investing activities	(56,187)	(7,339)	(2,444)
Cash flows from financing activities:
Net decrease in short-term borrowings	(795)	(1,074)	(84,756)
Repurchases of common stock	(371)	(1,391)	0
Proceeds from issuance of common stock	4,356	1,014	26,534
Excess tax benefits from stock-based compensation	2,190	1,358	0
Debt issuance costs	0	(143)	(1,313)
Net cash provided by (used in) financing activities	5,380	(236)	(59,535)
Net increase in cash and cash equivalents	40,239	63,832	1,197
Cash and cash equivalents, at beginning of year	76,016	12,184	10,987
Cash and cash equivalents, at end of year	116,255	76,016	12,184
Supplemental Disclosure of Cash Flow Information
Income taxes paid (refunded)	23,778	9,732	(25,978)
Interest paid	113	444	4,747
Capital lease obligations incurred	83	466	674
Purchases of property and equipment included in accounts payable	$ 1,486	$ 965	$ 388