Benefit Plans - Options Outstanding and Options Exercisable by Exercise Price with Weighted-Average Remaining Contractual Life for Options Outstanding and Weighted-Average Exercise Price (Detail)	12 Months Ended
	Dec. 31, 2021 $ / shares shares
Exercise Price 20-25 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	$ 20
Exercise Price Upper Range Limit	$ 25
Options Outstanding, Number | shares	137,585
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	1 year 2 months 1 day
Options Outstanding, Weighted-Average Grant Date Value	$ 24.60
Options Exercisable, Number | shares	137,585
Options Exercisable, Weighted-Average Grant Date Value	$ 24.60
Exercise Price 25-30 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	25
Exercise Price Upper Range Limit	30
Exercise Price 30-35 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	30
Exercise Price Upper Range Limit	$ 35
Options Outstanding, Number | shares	129,225
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	2 years 2 months 19 days
Options Outstanding, Weighted-Average Grant Date Value	$ 34.47
Options Exercisable, Number | shares	116,865
Options Exercisable, Weighted-Average Grant Date Value	$ 34.46
Exercise Price 35-40 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	35
Exercise Price Upper Range Limit	$ 40
Options Outstanding, Number | shares	6,800
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	2 years
Options Outstanding, Weighted-Average Grant Date Value	$ 39.19
Options Exercisable, Number | shares	6,800
Options Exercisable, Weighted-Average Grant Date Value	$ 39.19
Exercise Price 40-45 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	40
Exercise Price Upper Range Limit	$ 45
Options Outstanding, Number | shares	1,020
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	2 years 8 months 1 day
Options Outstanding, Weighted-Average Grant Date Value	$ 40.37
Options Exercisable, Weighted-Average Grant Date Value	40.37
Exercise Price 20-45 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Lower Range Limit	20
Exercise Price Upper Range Limit	$ 45
Options Outstanding, Number | shares	274,630
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	1 year 8 months 8 days
Options Outstanding, Weighted-Average Grant Date Value	$ 29.66
Options Exercisable, Number | shares	261,250
Options Exercisable, Weighted-Average Grant Date Value	$ 29.39