Investment Securities - Schedule of Securities Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,808,653	$ 1,716,218
Gross Unrealized Gains	9,359	17,200
Gross Unrealized Losses	56,715	44,650
Estimated Fair Value	1,761,297	1,688,768
GSE debentures
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	199,337	185,449
Gross Unrealized Gains	136	512
Gross Unrealized Losses	13,261	12,284
Estimated Fair Value	186,212	173,677
GSE CMOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	672,314	500,446
Gross Unrealized Gains	566	2,784
Gross Unrealized Losses	14,886	6,660
Estimated Fair Value	657,994	496,570
GSE MBSs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	317,137	334,476
Gross Unrealized Gains	604	3,009
Gross Unrealized Losses	12,969	11,740
Estimated Fair Value	304,772	325,745
Municipal obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	220,340	231,924
Gross Unrealized Gains	7,045	8,305
Gross Unrealized Losses	136	13
Estimated Fair Value	227,249	240,216
Corporate debt obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	24,530	39,209
Gross Unrealized Gains	771	863
Gross Unrealized Losses	166	49
Estimated Fair Value	25,135	40,023
U.S. Treasury bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	374,495	424,214
Gross Unrealized Gains	237	1,727
Gross Unrealized Losses	15,297	13,904
Estimated Fair Value	359,435	412,037
Foreign government obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	500	500
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 500	$ 500

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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