Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued in conjunction with the vesting and release of restricted stock units (in shares)			99,669
Common stock issued due to exercise of stock options (in shares)			954,527
Common stock issued in connection with employee stock purchase plan (in shares)			58,099
Proceeds from issuance of common stock		$ 4,821	$ 15,246
Repurchase of common stock, shares (in shares)		1,152,386	0
Repurchase of common stock		$ 19,600
Shares Paid for Tax Withholding for Share Based Compensation (in shares)			25,079	25,699
Payments related to tax withholding for share-based compensation		400	$ 500
Stock repurchase program, remaining authorized repurchase amount	$ 35,000		35,000
Share-based compensation expense recognized	1,879	5,820	5,938	$ 1,734
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense recognized	1,000	$ 3,500	3,100	1,100
Total unrecognized compensation expense related to non-vested stock options	$ 5,300		$ 5,300
Expected weighted-average period of recognition for unrecognized compensation expense			2 years 1 month 9 days
Weighted-average grant date fair value of stock options granted (in usd per share)		$ 5.97	$ 8.71
Stock options granted (in shares)	253,844	670,733
Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense recognized	$ 900	$ 2,300	$ 2,800	$ 600
Expected weighted-average period of recognition for unrecognized compensation expense			2 years 5 months
Total unrecognized compensation expense related to non-vested restricted stock	$ 6,100		$ 6,100
Weighted-average grant date fair value of stock options granted (in usd per share)		$ 16.06	$ 21.61
Stock options granted (in shares)		182,425	335,716