License and Consulting Agreements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty rate	7.00%
Royalty rate, amended	8.50%
Royalty obligation per year	$ 200
Royalty accrual reversal				$ 1,700
Payments to acquire asset agreement		$ 250	$ 0	0
In-process research and development		0	98	102
Issuance of common stock for acquired technology (less than $1.0 million)				102
Asset Purchase Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Stock issued for asset agreement				$ 100
Stock issued for asset agreement, shares				72,992
Payments to acquire asset agreement		$ 200		$ 200
In-process research and development			$ 300	$ 300
Issuance of common stock for acquired technology, shares		72,992
Issuance of common stock for acquired technology (less than $1.0 million)		$ 100