Securities - Reconciliation of Held-to-Maturity Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 836,523	$ 923,415
Gross Unrealized Gains	132	70
Gross Unrealized Losses	(133,946)	(162,923)
Allowance for Credit Losses	(146)	(107)	$ (181)
Fair Value	702,563	760,455
U.S. government agencies
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	10,406	11,099
Gross Unrealized Gains	7	11
Gross Unrealized Losses	(499)	(725)
Allowance for Credit Losses	0	0
Fair Value	9,914	10,385
Mortgage-backed securities, residential
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	332,509	360,683
Gross Unrealized Gains	82	57
Gross Unrealized Losses	(52,165)	(58,128)
Allowance for Credit Losses	0	0
Fair Value	280,426	302,612
Collateralized mortgage obligations, residential
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	12,243	13,026
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2,796)	(2,570)
Allowance for Credit Losses	0	0
Fair Value	9,447	10,456
Mortgage-backed securities, multifamily
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	4,145	5,094
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(651)	(747)
Allowance for Credit Losses	0	0
Fair Value	3,494	4,347
Obligations of states and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	474,220	530,513
Gross Unrealized Gains	43	2
Gross Unrealized Losses	(77,379)	(100,400)
Allowance for Credit Losses	(25)	(7)
Fair Value	396,859	430,108
Corporate debt securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	3,000	3,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(456)	(353)
Allowance for Credit Losses	(121)	(100)
Fair Value	$ 2,423	$ 2,547