Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation - Summary of Net Cash Proceeds from Exercise of Stock Options Less Shares Used for Minimum Withholding Taxes and Intrinsic Value of Options Exercised (Detail)

v3.19.1
Stock-Based Compensation - Summary of Net Cash Proceeds from Exercise of Stock Options Less Shares Used for Minimum Withholding Taxes and Intrinsic Value of Options Exercised (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]    
Net cash proceeds $ 2,622 $ 265
Intrinsic value of options exercised $ 7,569 $ 1,347