CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	[1]
Current assets
Cash and cash equivalents	$ 9,886	$ 10,210
Restricted cash	971	1,293
Accounts receivable, net	9,983	12,906
Prepaid expenses and other current assets	3,773	4,642
Total current assets	24,613	29,051
Property and equipment, net	9,985	11,815
Right-of-use assets, operating leases	10,410	0
Goodwill	1,936	1,943
Intangible assets, net	938	1,938
Other non-current assets	1,549	2,045
Total assets	49,431	46,792
Current liabilities
Accounts payable	1,911	2,699
Accrued expenses and other current liabilities	9,719	10,632
Operating lease liabilities	5,423	0
Total current liabilities	17,053	13,331
Operating lease liabilities, non-current	6,524	0
Other long-term liabilities	2,299	4,090
Total liabilities	25,876	17,421
Commitments and contingencies (Note 13)
Stockholders' equity
Common stock, $0.001 par value - 142,857 shares authorized, 6,623 and 5,938 shares issued and outstanding at June 30, 2019 and December 31, 2018, respectively	7	6
Additional paid-in capital	297,903	295,116
Accumulated deficit	(273,322)	(264,713)
Accumulated other comprehensive loss	(1,033)	(1,038)
Total stockholders' equity	23,555	29,371
Total liabilities and stockholders' equity	$ 49,431	$ 46,792

[1] Derived from the Company's audited consolidated financial statements as of December 31, 2018.