Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 147,297	$ 133,407
Short-term restricted cash	730	750
Accounts receivable, net	74,429	75,302
Inventories, net	129,554	120,544
Prepaid expenses and other current assets	10,925	9,772
Total current assets	362,935	339,775
Property, plant and equipment, net	36,312	36,168
Long-term restricted cash	6,915	6,723
Deferred income taxes	77,005	83,148
Other assets	25,264	22,404
Total assets	508,431	488,218
Current liabilities:
Accounts payable	32,633	32,642
Accrued compensation	12,727	20,955
Warranty	4,698	4,112
Income taxes	163	273
Deferred revenue	11,927	16,181
Other current liabilities	4,542	5,124
Total current liabilities	66,690	79,287
Sale leaseback obligation	47,735	47,714
Long-term deferred revenue	3,248	1,964
Other long-term liabilities	5,144	5,643
Total liabilities	122,817	134,608
Commitments and contingencies (Note 13)
Stockholders' equity:
Common stock, $0.001 par value, 75,000 shares authorized; 32,331 shares issued and outstanding at June 30, 2018; 32,048 shares issued and outstanding at December 31, 2017	32	32
Additional paid-in capital	559,207	556,147
Accumulated deficit	(174,561)	(204,745)
Accumulated other comprehensive income	936	2,176
Total stockholders' equity	385,614	353,610
Total liabilities and stockholders' equity	$ 508,431	$ 488,218