XML 80 R59.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stock-Based Compensation - Summary of Shares Available for Grant (Detail) - shares
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Stock Options [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares Available for Grant, Beginning balances 2,466,246 2,202,239 1,856,709
Shares Available for Grant, Additional shares reserved 1,189,502 1,155,474 1,125,742
Shares Available for Grant, Shares forfeited for tax 28,107 13,094  
Shares Available for Grant, Ending balances 2,980,762 2,466,246 2,202,239
Employee Stock Option and Restricted Stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares Available for Grant, Options and other than options granted (805,653) (1,002,063) (856,043)
Shares Available for Grant, Options and other than options forfeited or cancelled 102,560 97,502 75,831