Debt and Fair Value of Financial Instruments - Schedule of Roll Forward of Warrant Liability Classified as Level 3 and Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of warrant liability	$ 561	$ (147)
Ending balance	1,100	1,100
Fair Value, Measurements, Recurring [Member] | Basis of Fair Value Measurements, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance		1,210
Change in fair value of warrant liability		(147)
Ending balance	$ 1,063	$ 1,063