Marketable Securities - Held to Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Amortized cost
Amortized cost	$ 612,731	$ 683,369
Gross unrealized holding gains
Gross unrealized holding gains	0	4
Gross unrealized holding losses
Gross unrealized holding losses	(94,348)	(77,444)
Fair value
Fair value	518,383	605,929
U.S. government-sponsored enterprises
Amortized cost
Due after one year through five years	107,991	16,477
Due after five years through ten years		107,988
Gross unrealized holding gains
Due after one year through five years	0	0
Due after five years through ten years		0
Gross unrealized holding losses
Due after one year through five years	(9,180)	(98)
Due after five years through ten years		(8,216)
Fair value
Due after one year through five years	98,811	16,379
Due after five years through ten years		99,772
Mortgage-backed securities
Amortized cost
Due after one year through five years	31,669
Due after five years through ten years	88,239
Amortized cost	504,740	558,904
Gross unrealized holding gains
Gross unrealized holding gains	0	4
Gross unrealized holding losses
Gross unrealized holding losses	(85,168)	(69,130)
Fair value
Due after one year through five years	28,184
Due after five years through ten years	75,815
Fair value	419,572	489,778
Fixed rate pass-through
Amortized cost
Amortized cost	108,007	118,614
Gross unrealized holding gains
Gross unrealized holding gains	0	1
Gross unrealized holding losses
Gross unrealized holding losses	(15,411)	(12,362)
Fair value
Fair value	92,596	106,253
Variable rate pass-through
Amortized cost
Amortized cost	280	310
Gross unrealized holding gains
Gross unrealized holding gains	0	3
Gross unrealized holding losses
Gross unrealized holding losses	0	0
Fair value
Fair value	280	313
Fixed rate agency CMOs
Amortized cost
Amortized cost	395,925	439,452
Gross unrealized holding gains
Gross unrealized holding gains	0	0
Gross unrealized holding losses
Gross unrealized holding losses	(69,754)	(56,766)
Fair value
Fair value	326,171	382,686
Variable rate agency CMOs
Amortized cost
Amortized cost	528	528
Gross unrealized holding gains
Gross unrealized holding gains	0	0
Gross unrealized holding losses
Gross unrealized holding losses	(3)	(2)
Fair value
Fair value	$ 525	$ 526

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Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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