Annual report pursuant to Section 13 and 15(d)

Summary of Restricted Stock Award Activity (Detail)

v3.20.4
Summary of Restricted Stock Award Activity (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock grants vested 832,609 209,821 250,442
Compensation expense recognized during the period $ 15,473 $ 10,185 $ 9,655
Fair value of restricted shares that vested during the period 16,870 8,024 9,501
Income tax deduction and benefit recognized upon vesting of restricted stock and restricted stock unit awards $ 5,620 $ 1,516 $ 1,744
Restricted Stock Units (RSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock grants vested 208,204 90,895 127,084
Accumulated dividends paid upon vesting of restricted stock unit awards $ 942 $ 386 $ 526
Compensation expense recognized during the period 3,931 4,430 4,681
Fair value of restricted shares that vested during the period 5,050 3,658 4,846
Income tax deduction and benefit recognized upon vesting of restricted stock and restricted stock unit awards $ 788 $ 397 $ 708