Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 26, 2011
Cash flows from operating activities:
Net income (loss)	$ (3,224)		$ 6,574
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	2,442		2,769
Share-based compensation expense	1,044		1,048
Deferred income taxes	(23)		(431)
Other accrued liabilities	33		2
Excess tax benefits from stock options exercised			(29)
Changes in current assets and liabilities:
Accounts receivable	5,670		9,039
Inventories	59		(4,973)
Other current assets	(711)		288
Accounts payable	(2,204)		505
Deferred profit	(519)		(5,581)
Income taxes payable, including excess stock option exercise benefit	421		1,732
Accrued compensation, warranty and other liabilities	(2,313)		(3,518)
Net cash provided by operating activities	675		7,425
Cash flows from investing activities:
Purchases of short-term investments	(20,154)		(20,727)
Sales and maturities of short-term investments	18,097		15,003
Purchases of property, plant and equipment	(957)		(187)
Other assets	(17)		(50)
Net cash used in investing activities	(3,031)		(5,961)
Cash flows from financing activities:
Cash dividends	(1,458)		(1,436)
Issuance of stock, net of repurchases	231		562
Excess tax benefits from stock options exercised			29
Net cash used in financing activities	(1,227)		(845)
Effect of exchange rate changes on cash and cash equivalents	787		2,269
Net increase (decrease) in cash and cash equivalents	(2,796)		2,888
Cash and cash equivalents at beginning of period	53,262	[1]	45,921
Cash and cash equivalents at end of period	50,466		48,809
Supplemental disclosure of cash flow information:
Cash paid (refunded) for income taxes	(279)		528
Inventory capitalized as property, plant and equipment	415		299
Dividends declared but not yet paid	$ 1,462		$ 1,442

[1] Derived from December 31, 2011 audited financial statements.