Condensed Consolidated Balance Sheets (Parenthetical) $ in Thousands	Jun. 30, 2018 USD ($) shares	Dec. 31, 2017 USD ($) shares
Statement Of Financial Position [Abstract]
Accounts receivable, related party amount, current | $	$ 881	$ 821
Prepaid expenses and other current assets, related party amount | $	559	1,871
Accrued expenses related party amount, current | $	78	0
Deferred revenue non-current related party amount | $	$ 0	$ 91
Common stock, shares authorized	47,520,292	41,092,969
Common stock, shares issued	47,481,196	41,037,121
Common stock, shares outstanding	47,071,835	40,592,248
Common stock, conditional capital	19,699,821	16,419,632
Treasury stock, shares	409,361	444,873