Securities - Reconciliation of Held-to-Maturity Securities (Detail) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 923,415,000	$ 825,137,000
Gross Unrealized Gains	70,000	2,046,000
Gross Unrealized Losses	(162,923,000)	(11,791,000)
Allowance for Credit Losses	(107,000)	(181,000)
Fair Value	760,455,000	815,211,000
U.S. government agencies
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	11,099,000	18,672,000
Gross Unrealized Gains	11,000	293,000
Gross Unrealized Losses	(725,000)	0
Allowance for Credit Losses	0	0
Fair Value	10,385,000	18,965,000
Mortgage-backed securities, residential
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	360,683,000	370,247,000
Gross Unrealized Gains	57,000	718,000
Gross Unrealized Losses	(58,128,000)	(5,989,000)
Allowance for Credit Losses	0	0
Fair Value	302,612,000	364,976,000
Collateralized mortgage obligations, residential
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	13,026,000	13,921,000
Gross Unrealized Gains	0	168,000
Gross Unrealized Losses	(2,570,000)	0
Allowance for Credit Losses	0	0
Fair Value	10,456,000	14,089,000
Mortgage-backed securities, multifamily
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	5,094,000	2,710,000
Gross Unrealized Gains	0	26,000
Gross Unrealized Losses	(747,000)	(2,000)
Allowance for Credit Losses	0	0
Fair Value	4,347,000	2,734,000
Obligations of states and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	530,513,000	416,587,000
Gross Unrealized Gains	2,000	810,000
Gross Unrealized Losses	(100,400,000)	(5,800,000)
Allowance for Credit Losses	(7,000)	(21,000)
Fair Value	430,108,000	411,576,000
Corporate debt securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	3,000,000	3,000,000
Gross Unrealized Gains	0	31,000
Gross Unrealized Losses	(353,000)	0
Allowance for Credit Losses	(100,000)	(160,000)
Fair Value	$ 2,547,000	$ 2,871,000