Annual report pursuant to Section 13 and 15(d)

Share-based Compensation - Summary of Transactions for Non-Vested Stock Options (Detail)

v3.19.3.a.u2
Share-based Compensation - Summary of Transactions for Non-Vested Stock Options (Detail) - 2007 and 2013 Plan - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]      
Number of Shares, Non-vested options outstanding at beginning of period (shares) 0 9,335 46,340
Number of Shares, Options granted (shares) 0    
Number of Shares, Options vested (shares)   (9,335) (37,005)
Number of Shares, Options forfeited (shares)   0 0
Number of Shares, Non-vested options outstanding at end of period (shares)   0 9,335
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]      
Weighted-Average Exercise Price Per Share, Non-vested options outstanding at beginning of period (in USD per share) $ 0 $ 23.47 $ 22.42
Weighted-Average Exercise Price Per Share, Options vested (in USD per share)   23.47 22.16
Weighted-Average Exercise Price Per Share, Options forfeited (in USD per share)   0 0
Weighted-Average Exercise Price Per Share, Non-vested options outstanding at end of period (in USD per share)   $ 0 $ 23.47