Investment Securities - Held-to-Maturity with Unrecognized Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value
Less than 12 months	$ 364,196	$ 1,560,831
12 months or longer	2,206,675	1,052,753
Total	2,570,871	2,613,584
Unrecognized Losses
Less than 12 months	(33,222)	(280,316)
12 months or longer	(419,154)	(165,370)
Total	(452,376)	(445,686)
U.S. government-sponsored entities and agencies
Fair Value
Less than 12 months	81,251	354,293
12 months or longer	574,195	302,066
Total	655,446	656,359
Unrecognized Losses
Less than 12 months	(8,138)	(110,523)
12 months or longer	(158,933)	(52,287)
Total	(167,071)	(162,810)
Mortgage-backed securities
Fair Value
Less than 12 months	244,643	367,849
12 months or longer	683,853	615,114
Total	928,496	982,963
Unrecognized Losses
Less than 12 months	(24,690)	(42,438)
12 months or longer	(117,501)	(81,416)
Total	(142,191)	(123,854)
States and political subdivisions
Fair Value
Less than 12 months	38,302	838,689
12 months or longer	948,627	135,573
Total	986,929	974,262
Unrecognized Losses
Less than 12 months	(394)	(127,355)
12 months or longer	(142,720)	(31,667)
Total	$ (143,114)	$ (159,022)

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

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-Topic 320
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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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