Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Current assets
Cash and cash equivalents	$ 37,218	$ 46,877
Accounts receivable, net	30,464	35,071
Inventories, net	128,719	120,023
Prepaid expenses and other current assets	10,532	10,062
Total current assets	206,933	212,033
Property, plant and equipment, net	36,507	37,204
Long-term restricted cash	107	104
Other assets	12,263	19,904
Total assets	255,810	269,245
Current liabilities
Accounts payable	17,861	19,551
Accrued compensation	9,087	8,285
Warranty	3,110	3,556
Income taxes	576	495
Deferred revenue	7,216	10,786
Other current liabilities	4,298	4,799
Total current liabilities	42,148	47,472
Long-term deferred revenue	1,241	1,488
Other long-term liabilities	6,000	5,730
Total liabilities	49,389	54,690
Commitments and contingencies (Note 10)
Stockholders' equity
Preferred stock
Common stock	108	107
Additional paid-in capital	501,169	499,332
Treasury stock	(1,218)	(1,218)
Accumulated deficit	(298,471)	(288,443)
Accumulated other comprehensive income	4,833	4,777
Total stockholders' equity	206,421	214,555
Total liabilities and stockholders' equity	$ 255,810	$ 269,245