Marketable Securities - Held To Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Amortized cost
Amortized cost	$ 784,208	$ 814,839
Gross unrealized holding gains
Gross unrealized holding gains	0	1
Gross unrealized holding losses
Gross unrealized holding losses	(120,916)	(115,334)
Fair value
Fair value	663,292	699,506
U.S. government-sponsored enterprises
Amortized cost
Due after one year through five years	89,472	69,471
Due after five years through ten years	34,988	54,987
Gross unrealized holding gains
Due after one year through five years	0	0
Due after five years through ten years	0	0
Gross unrealized holding losses
Due after one year through five years	(10,845)	(8,100)
Due after five years through ten years	(5,645)	(8,700)
Fair value
Due after one year through five years	78,627	61,371
Due after five years through ten years	29,343	46,287
Mortgage-backed securities
Amortized cost
Due after one year through five years	20,010
Due after five years through ten years	20,201
Amortized cost	659,748	690,381
Gross unrealized holding gains
Gross unrealized holding gains	0	1
Gross unrealized holding losses
Gross unrealized holding losses	(104,426)	(98,534)
Fair value
Due after one year through five years	17,581
Due after five years through ten years	16,321
Fair value	555,322	591,848
Fixed rate pass-through
Amortized cost
Amortized cost	140,245	147,874
Gross unrealized holding gains
Gross unrealized holding gains	0	0
Gross unrealized holding losses
Gross unrealized holding losses	(21,704)	(20,834)
Fair value
Fair value	118,541	127,040
Variable rate pass-through
Amortized cost
Amortized cost	414	449
Gross unrealized holding gains
Gross unrealized holding gains	0	1
Gross unrealized holding losses
Gross unrealized holding losses	(4)	0
Fair value
Fair value	410	450
Fixed rate agency CMOs
Amortized cost
Amortized cost	518,560	541,529
Gross unrealized holding gains
Gross unrealized holding gains	0	0
Gross unrealized holding losses
Gross unrealized holding losses	(82,714)	(77,694)
Fair value
Fair value	435,846	463,835
Variable rate agency CMOs
Amortized cost
Amortized cost	529	529
Gross unrealized holding gains
Gross unrealized holding gains	0	0
Gross unrealized holding losses
Gross unrealized holding losses	(4)	(6)
Fair value
Fair value	$ 525	$ 523

Debt Securities, Held-to-Maturity, After Five Through Ten Years, Gross Unrealized Gain

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Debt Securities, Held-to-Maturity, After Five Through Ten Years, Gross Unrealized Loss

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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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