Employee Benefit Plans (Combined Activity in Corporations Defined Benefit Pension Plans) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Fair value of plan assets at beginning of year	$ 182,088	$ 174,173	$ 152,820
Actual return on plan assets	24,908	16,599	29,945
Employer contributions	1,236	1,201	1,163
Benefits paid	(10,485)	(9,885)	(9,755)
Fair value of plan assets at end of year	197,747	182,088	174,173
Benefit obligation at beginning of year	197,593	186,641	167,107
Interest cost	3,341	5,010	6,472
Actuarial (gain) loss	(4,524)	15,827	22,817
Benefits paid	(10,485)	(9,885)	(9,755)
Benefit obligation at end of year	185,925	197,593	186,641
Funded status of the plan at end of year and accrued benefit (liability) recognized	11,822	(15,505)	(12,468)
Accumulated benefit obligation at end of year	$ 185,925	$ 197,593	$ 186,641