Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 34,639	$ 44,986
Accounts receivable, net	30,220	24,843
Inventories, net	96,412	100,234
Restricted cash	104	106
Prepaid expenses and other current assets	6,025	5,056
Total current assets	167,400	175,225
Property, plant and equipment, net	32,964	34,413
Other assets	13,406	12,520
Total assets	213,770	222,158
Current liabilities
Accounts payable	16,188	10,166
Accrued compensation	6,559	7,283
Warranty	1,419	1,700
Income taxes	226	278
Deferred revenue	5,728	6,423
Other current liabilities	4,432	3,932
Total current liabilities	34,552	29,782
Long-term deferred revenue	259	456
Other long-term liabilities	5,829	5,844
Total liabilities	40,640	36,082
Commitments and contingencies (Note 13)
Stockholders' equity
Preferred stock, $0.001 par value, 30,000 shares authorized; none issued or outstanding
Common stock, $0.001 par value, 300,000 shares authorized; 108,772 shares issued and 108,652 shares outstanding at June 30, 2013;108,293 shares issued and 108,173 shares outstanding at December 31, 2012	109	108
Additional paid-in capital	506,647	504,643
Treasury stock, at cost, 120 shares at June 30, 2013 and December 31, 2012	(1,218)	(1,218)
Accumulated deficit	(335,485)	(322,477)
Accumulated other comprehensive income	3,077	5,020
Total stockholders' equity	173,130	186,076
Total liabilities and stockholders' equity	$ 213,770	$ 222,158