Marketable Securities - Held to Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Amortized cost
Amortized cost	$ 630,802	$ 683,369
Gross unrealized holding gains
Gross unrealized holding gains	1	4
Gross unrealized holding losses
Gross unrealized holding losses	(80,387)	(77,444)
Fair value
Fair value	550,416	605,929
U.S. government-sponsored enterprises
Amortized cost
Due after one year through five years	107,990	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	(8,338)	(98)
Due after five years through ten years		(8,216)
Fair value
Due after one year through five years	99,652	16,379
Due after five years through ten years		99,772
Mortgage-backed securities
Amortized cost
Due after one year through five years	31,683
Due after five years through ten years	91,452
Amortized cost	522,812	558,904
Gross unrealized holding gains
Gross unrealized holding gains	1	4
Gross unrealized holding losses
Gross unrealized holding losses	(72,049)	(69,130)
Fair value
Due after one year through five years	28,634
Due after five years through ten years	81,088
Fair value	450,764	489,778
Fixed rate pass-through
Amortized cost
Amortized cost	111,751	118,614
Gross unrealized holding gains
Gross unrealized holding gains	0	1
Gross unrealized holding losses
Gross unrealized holding losses	(12,885)	(12,362)
Fair value
Fair value	98,866	106,253
Variable rate pass-through
Amortized cost
Amortized cost	294	310
Gross unrealized holding gains
Gross unrealized holding gains	1	3
Gross unrealized holding losses
Gross unrealized holding losses	0	0
Fair value
Fair value	295	313
Fixed rate agency CMOs
Amortized cost
Amortized cost	410,239	439,452
Gross unrealized holding gains
Gross unrealized holding gains	0	0
Gross unrealized holding losses
Gross unrealized holding losses	(59,164)	(56,766)
Fair value
Fair value	351,075	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	0	(2)
Fair value
Fair value	$ 528	$ 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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