Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 108,558	$ 70,791
Accounts receivable, net	48,561	50,573
Inventories, net	122,574	113,853
Prepaid expenses and other current assets	9,985	5,512
Total current assets	289,678	240,729
Property, plant and equipment, net	31,617	30,840
Long-term restricted cash	6,793	6,864
Other assets	26,654	23,798
Total assets	354,742	302,231
Current liabilities:
Accounts payable	27,606	24,996
Accrued compensation	12,170	5,142
Warranty	3,537	2,426
Income taxes	255	240
Deferred revenue	13,832	10,335
Other current liabilities	4,957	4,592
Total current liabilities	62,357	47,731
Sale leaseback obligation	47,692	47,586
Long-term deferred revenue	1,070	674
Other long-term liabilities	5,185	4,785
Total liabilities	116,304	100,776
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.001 par value, 30,000 shares authorized; none issued or outstanding
Common stock, $0.001 par value, 75,000 shares authorized; 31,180 shares issued and outstanding at June 30, 2017; 29,518 shares issued and outstanding at December 31, 2016	31	30
Additional paid-in capital	546,491	535,408
Accumulated deficit	(308,266)	(331,704)
Accumulated other comprehensive income (loss)	182	(2,279)
Total stockholders' equity	238,438	201,455
Total liabilities and stockholders' equity	$ 354,742	$ 302,231

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.