Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents, see notes 1 and 7	$ 66,882	$ 63,961
Restricted cash	4,012	4,012
Accounts receivable	10,684	22,650
Inventory	39,150	32,752
Prepaid expenses and other current assets	9,738	7,855
Total current assets	130,466	131,230
Restricted cash	43,854	43,823
Property, plant, and equipment, net of accumulated depreciation of $28,351 and $27,970, respectively	8,750	7,255
Leased property, net of accumulated depreciation of $1,877 and $1,700, respectively	13,237	1,667
Note receivable	367	383
Goodwill	8,827	8,478
Intangible assets, net	4,656	4,644
Other assets	12,012	11,976
Total assets	222,169	209,456
Current liabilities:
Accounts payable	23,045	20,455
Accrued expenses	9,968	9,852
Short-term borrowing	23,961
Product warranty reserve	486	406
Accrual for loss contracts related to service	3,400	4,100
Deferred revenue	3,947	4,468
Finance obligations	2,528	2,671
Other current liabilities	376	754
Total current liabilities	67,711	42,706
Accrual for loss contracts related to service	4,902	5,950
Deferred revenue	13,274	13,997
Common stock warrant liability	4,317	5,735
Finance obligations	14,396	14,809
Other liabilities	385	370
Total liabilities	104,985	83,567
Redeemable preferred stock
Series C redeemable convertible preferred stock, $0.01 par value per share (aggregate involuntary liquidation preference $16,664) 10,431 shares authorized; Issued and outstanding: 5,231 at March 31, 2016 and December 31, 2015	1,153	1,153
Stockholders' equity:
Common stock, $0.01 par value per share; 450,000,000 shares authorized; Issued (including shares in treasury): 180,720,285 at March 31, 2016 and 180,567,444 at December 31, 2015	1,807	1,806
Additional paid-in capital	1,121,408	1,118,917
Accumulated other comprehensive income	1,381	798
Accumulated deficit	(1,005,656)	(993,876)
Less common stock in treasury: 479,953 at March 31, 2016 and December 31, 2015	(2,909)	(2,909)
Total stockholders' equity	116,031	124,736
Total liabilities, redeemable preferred stock, and stockholders' equity	$ 222,169	$ 209,456