Stockholders Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Oct. 31, 2011
Stockholders Equity Note [Line Items]
Issuance of common stock on exercise of option	500
Common stock issued upon vesting of RSUs	423,113	346,045
Common stock, shares authorized	100,000,000		100,000,000
Common stock, par value	$ 0.0001		$ 0.0001
Warrant expiration date	Oct. 04, 2021
Issuance of common stock on exercise of option	5,172,638		5,042,325
Weighted-average grant date fair value of options granted	$ 7.86
Non Vested Stock Options
Stockholders Equity Note [Line Items]
Estimated unrecognized employee compensation cost related to non-vested stock options granted	$ 8.7
Estimated unrecognized employee compensation cost related to non-vested stock options granted, Weighted-average period of recognition	1 year 10 months 24 days
Restricted Stock Units
Stockholders Equity Note [Line Items]
Common stock issued upon vesting of RSUs	423,113
Issuance of common stock on exercise of vesting of RSUs granted	1,051,303
Estimated unrecognized employee compensation cost related to non-vested stock options granted	$ 30.6
Estimated unrecognized employee compensation cost related to non-vested stock options granted, Weighted-average period of recognition	1 year 7 months 6 days
Weighted-average grant date fair value of options granted	$ 7.86	$ 21.82
Weighted-average grant date fair value of RSUs	$ 10.61	$ 22.14
2011 Plan
Stockholders Equity Note [Line Items]
Common stock shares reserved for issuance	12,529,412
Stock options, award vesting period	3 years
Issuance of common stock on exercise of option	6,230,574
Issuance of common stock on exercise of vesting of RSUs granted	6,230,574
Common stock shares available for future issuance	2,122,539
2017 Employment Inducement Incentive Award Plan
Stockholders Equity Note [Line Items]
Common stock shares reserved for issuance	2,000,000
Stock options, award vesting period	3 years
Issuance of common stock on exercise of option	1,258,685
Issuance of common stock on exercise of vesting of RSUs granted	1,258,685
Common stock shares available for future issuance	538,182
Maximum | 2011 Plan
Stockholders Equity Note [Line Items]
Stock options granted, term	10 years
Maximum | 2017 Employment Inducement Incentive Award Plan
Stockholders Equity Note [Line Items]
Stock options granted, term	10 years
Common Stock
Stockholders Equity Note [Line Items]
Issuance of common stock on exercise of option	500	67,625
Shares of common stock that could be acquired by warrant	2,116,250
Common stock price	$ 16
Common Stock | Alan Auerbach | Minimum
Stockholders Equity Note [Line Items]
Minimum ownership percentage of outstanding shares of common stock the president need to maintain after issuance of warrants				20.00%