Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 2,090	$ 46,014
Restricted cash	14,830	11,219
Accounts receivable	15,268	11,923
Inventory	42,703	29,940
Prepaid expenses and other current assets	13,126	11,837
Total current assets	88,017	110,933
Restricted cash	37,202	43,403
Property, plant, and equipment, net of accumulated depreciation of $30,594 and $29,666, respectively	8,375	8,246
Leased property, net of accumulated amortization of $7,799 and $4,544, respectively	70,293	54,060
Goodwill	9,006	8,291
Intangible assets, net of accumulated amortization of 1,382 and $1,032, respectively	3,926	3,933
Other assets	11,761	11,966
Total assets	228,580	240,832
Current liabilities:
Accounts payable	28,149	32,112
Accrued expenses	6,336	8,519
Accrual for loss contracts related to service		752
Deferred revenue	5,050	5,736
Finance obligations	21,197	14,787
Current portion of long-term debt	5,383	2,964
Other current liabilities	995	1,615
Total current liabilities	67,110	66,485
Deferred revenue	17,312	17,413
Common stock warrant liability	3,779	11,387
Finance obligations	22,743	29,767
Long-term debt	17,955	20,829
Other liabilities	261	241
Total liabilities	129,160	146,122
Stockholders' equity:
Common stock, $0.01 par value per share; 450,000,000 shares authorized; Issued (including shares in treasury): 225,295,596 at June 30, 2017 and 191,723,974 at December 31, 2016	2,253	1,917
Additional paid-in capital	1,215,879	1,137,482
Accumulated other comprehensive income	1,403	247
Accumulated deficit	(1,118,177)	(1,051,467)
Less common stock in treasury: 582,328 at June 30, 2017 and December 31, 2016	(3,091)	(3,091)
Total stockholders' equity	98,267	85,088
Total liabilities, redeemable preferred stock, and stockholders' equity	228,580	240,832
Series C Redeemable Convertible Preferred Stock
Redeemable preferred stock
Redeemable preferred stock	$ 1,153	1,153
Series D Redeemable Convertible Preferred Stock
Redeemable preferred stock
Redeemable preferred stock		$ 8,469