Summary of Significant Accounting Policies - Schedule of aggregate fair values of the Company's common stock warrants and contingent consideration for which fair value is determined by Level 3 inputs (Details) - Level 3 - Recurring $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Warrants
Fair values of the Company's liabilities determined by Level 3 inputs
Balance at beginning of the period	$ 99
Fair value of warrants to be issued upon borrowing / Initial fair value of acquisition related consideration	88
Warrants extinguished upon termination of SVB Loan Agreement	(88)
Change in fair value	95
Balance at the end of the period	194
Deferred Consideration Liability
Fair values of the Company's liabilities determined by Level 3 inputs
Balance at beginning of the period	395
Fair value of warrants to be issued upon borrowing / Initial fair value of acquisition related consideration	966
Change in fair value	(106)
Balance at the end of the period	1,255
Contingent Consideration Liability
Fair values of the Company's liabilities determined by Level 3 inputs
Balance at beginning of the period	1,242
Fair value of warrants to be issued upon borrowing / Initial fair value of acquisition related consideration	9,946
Change in fair value	1,131
Balance at the end of the period	$ 12,319