Employee Benefit Plans (Combined Activity in Corporations Defined Benefit Pension Plans) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Fair value of plan assets at beginning of year	$ 161,823	$ 197,747	$ 182,088
Actual return on plan assets	22,477	(26,108)	24,908
Employer contributions	1,105	1,114	1,236
Benefits paid	(10,794)	(10,930)	(10,485)
Fair value of plan assets at end of year	174,611	161,823	197,747
Benefit obligation at beginning of year	143,944	185,925	197,593
Interest cost	6,983	4,017	3,341
Actuarial (gain) loss	2,239	(35,068)	(4,524)
Benefits paid	(10,794)	(10,930)	(10,485)
Benefit obligation at end of year	142,372	143,944	185,925
Funded status of the plan at end of year and accrued benefit (liability) recognized	32,239	17,879	11,822
Accumulated benefit obligation at end of year	$ 142,372	$ 143,944	$ 185,925