Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 42,441	$ 44,986
Accounts receivable, net	23,150	24,843
Inventories, net	98,729	100,234
Restricted cash	103	106
Prepaid expenses and other current assets	5,519	5,056
Total current assets	169,942	175,225
Property, plant and equipment, net	33,663	34,413
Other assets	12,352	12,520
Total assets	215,957	222,158
Current liabilities
Accounts payable	13,793	10,166
Accrued compensation	8,900	7,283
Warranty	1,539	1,700
Income taxes	356	278
Deferred revenue	5,714	6,423
Other current liabilities	3,768	3,932
Total current liabilities	34,070	29,782
Long-term deferred revenue	321	456
Other long-term liabilities	5,713	5,844
Total liabilities	40,104	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; 108,405 shares issued and 108,285 shares outstanding at March 31, 2013;108,293 shares issued and 108,173 shares outstanding at December 31, 2012	108	108
Additional paid-in capital	505,478	504,643
Treasury stock, at cost, 120 shares at March 31, 2013 and December 31, 2012	(1,218)	(1,218)
Accumulated deficit	(331,465)	(322,477)
Accumulated other comprehensive income	2,950	5,020
Total stockholders' equity	175,853	186,076
Total liabilities and stockholders' equity	$ 215,957	$ 222,158