Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 66,143	$ 57,389
Accounts receivable	13,563	20,326
Inventory	28,570	19,375
Deposits on purchased inventory	7,542	7,043
Deferred cost of revenue	15,683	13,696
Prepaid expenses and other current assets	5,259	4,862
Total current assets	136,760	122,691
Property and equipment, net	13,587	11,564
Restricted cash	1,181	1,143
Intangible assets, net	68	78
Other assets	917	235
TOTAL ASSETS	152,513	135,711
Current liabilities:
Accounts payable	7,574	11,014
Accrued liabilities	7,650	7,207
Customer deposits	10,280	17,820
Deferred revenue, current portion	15,540	20,151
Total current liabilities	41,044	56,192
Deferred revenue, net of current portion	4,393	3,238
Long-term debt	44,599	44,504
Warrant liabilities	15,411	22,420
Other long-term liabilities	9,100	7,370
TOTAL LIABILITIES	114,547	133,724
Commitments and contingencies (Note 6)	0	0
Stockholders’ equity:
Convertible preferred stock, par value of $0.01 per share; 10,000,000 shares authorized at June 30, 2018 and December 31, 2017; no shares issued and outstanding at June 30, 2018 and December 31, 2017	0	0
Common stock, par value of $0.01 per share; 300,000,000 shares authorized at June 30, 2018 and December 31, 2017; 75,188,832 and 67,653,974 shares issued and outstanding at June 30, 2018 and December 31, 2017	741	666
Additional paid-in capital	386,610	321,174
Accumulated deficit	(349,385)	(319,853)
TOTAL STOCKHOLDERS’ EQUITY	37,966	1,987
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 152,513	$ 135,711