Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation Plans - Employee Stock Purchase Plan - Additional Information (Detail)

v3.7.0.1
Stock-Based Compensation Plans - Employee Stock Purchase Plan - Additional Information (Detail)
 3 Months Ended
Mar. 31, 2017
USD ($)
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Common stock shares available for issuance 5,528,976
Unrecognized stock-based compensation expense | $ $ 21,730,000
Unrecognized stock-based compensation expenses recognition period 3 years 2 months 27 days
Employee Stock Purchase Plan [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
ESPP offering period description The offering periods generally start on the first trading day on or after May 15 and November 15 of each year.
Length of purchase intervals 6 months
ESPP discount rate 10.00%
Common stock reserved and available for issuance 366,667
Common stock shares available for issuance 277,104
Common stock available for future issuance authorized annual share increase 366,667
Common stock available for future issuance authorized annual percentage increase 1.00%
Unrecognized stock-based compensation expense | $ $ 23,000
Unrecognized stock-based compensation expenses recognition period 1 month 13 days