Investment Securities - Schedule of Securities Available-for-sale (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,761,431	$ 1,716,218
Gross Unrealized Gains	8,287	17,200
Gross Unrealized Losses	51,008	44,650
Estimated Fair Value	1,718,710	1,688,768
GSE debentures
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	191,035	185,449
Gross Unrealized Gains	257	512
Gross Unrealized Losses	12,696	12,284
Estimated Fair Value	178,596	173,677
GSE CMOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	563,834	500,446
Gross Unrealized Gains	797	2,784
Gross Unrealized Losses	11,050	6,660
Estimated Fair Value	553,581	496,570
GSE MBSs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	326,216	334,476
Gross Unrealized Gains	2,027	3,009
Gross Unrealized Losses	12,119	11,740
Estimated Fair Value	316,124	325,745
Municipal obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	225,345	231,924
Gross Unrealized Gains	3,570	8,305
Gross Unrealized Losses	427	13
Estimated Fair Value	228,488	240,216
Corporate debt obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	35,359	39,209
Gross Unrealized Gains	760	863
Gross Unrealized Losses	125	49
Estimated Fair Value	35,994	40,023
U.S. Treasury bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	419,142	424,214
Gross Unrealized Gains	876	1,727
Gross Unrealized Losses	14,591	13,904
Estimated Fair Value	405,427	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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