Marketable Securities - Held To Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost
Amortized cost	$ 881,249	$ 768,154
Gross unrealized holding gains
Gross unrealized holding gains	0	350
Gross unrealized holding losses
Gross unrealized holding losses	(129,865)	(16,991)
Fair value
Fair value	751,384	751,513
U.S. government sponsored enterprises
Amortized cost
Due after one year through five years	29,478	16,478
Due after five years through ten years	94,977	107,973
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	(3,676)	(206)
Due after five years through ten years	(18,157)	(4,613)
Fair value
Due after one year through five years	25,802	16,272
Due after five years through ten years	76,820	103,360
Residential mortgage-backed securities
Amortized cost
Due after one year through five years	20,612
Due after five years through ten years	20,250
Amortized cost	756,794	643,703
Gross unrealized holding gains
Gross unrealized holding gains	0	350
Gross unrealized holding losses
Gross unrealized holding losses	(108,032)	(12,172)
Fair value
Due after one year through five years	17,568
Due after five years through ten years	15,879
Fair value	648,762	631,881
Fixed rate \| Pass-through
Amortized cost
Amortized cost	163,196	183,092
Gross unrealized holding gains
Gross unrealized holding gains	0	58
Gross unrealized holding losses
Gross unrealized holding losses	(24,684)	(2,161)
Fair value
Fair value	138,512	180,989
Fixed rate \| Agency CMOs
Amortized cost
Amortized cost	592,527	459,345
Gross unrealized holding gains
Gross unrealized holding gains	0	251
Gross unrealized holding losses
Gross unrealized holding losses	(83,325)	(10,011)
Fair value
Fair value	509,202	449,585
Variable rate \| Pass-through
Amortized cost
Amortized cost	542	667
Gross unrealized holding gains
Gross unrealized holding gains	0	24
Gross unrealized holding losses
Gross unrealized holding losses	(12)	0
Fair value
Fair value	530	691
Variable rate \| Agency CMOs
Amortized cost
Amortized cost	529	599
Gross unrealized holding gains
Gross unrealized holding gains	0	17
Gross unrealized holding losses
Gross unrealized holding losses	(11)	0
Fair value
Fair value	$ 518	$ 616

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

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