Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 65,623	$ 78,889
Accounts receivable, net	44,993	36,868
Inventories, net	117,001	109,408
Prepaid expenses and other current assets	4,701	4,792
Total current assets	232,318	229,957
Property, plant and equipment, net	30,804	30,031
Long-term restricted cash	6,865	6,936
Other assets	21,163	14,860
Total assets	291,150	281,784
Current liabilities
Accounts payable	20,241	19,849
Accrued compensation	4,508	9,059
Warranty	2,597	3,363
Income taxes	235	143
Deferred revenue	7,074	7,863
Other current liabilities	5,057	4,091
Total current liabilities	39,712	44,368
Sale leaseback obligation	47,586	47,586
Long-term deferred revenue	788	679
Other long-term liabilities	5,136	5,387
Total liabilities	93,222	98,020
Commitments and contingencies (Note 14)
Stockholders' equity
Common stock, $0.001 par value, 75,000 shares authorized; 29,347 shares issued and outstanding at September 30, 2016; 29,025 shares issued and 28,995 shares outstanding at December 31, 2015	29	29
Additional paid-in capital	533,392	529,089
Treasury stock, at cost, no shares at September 30, 2016 and 30 shares at December 31, 2015		(1,218)
Accumulated deficit	(335,669)	(342,705)
Accumulated other comprehensive income (loss)	176	(1,431)
Total stockholders' equity	197,928	183,764
Total liabilities and stockholders' equity	$ 291,150	$ 281,784