Investment Securities - Held-to-Maturity with Unrecognized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value
Less than 12 months	$ 64,441	$ 1,560,831
12 months or longer	2,329,330	1,052,753
Total	2,393,771	2,613,584
Unrecognized Losses
Less than 12 months	(4,877)	(280,316)
12 months or longer	(629,416)	(165,370)
Total	(634,293)	(445,686)
U.S. government-sponsored entities and agencies
Fair Value
Less than 12 months	0	354,293
12 months or longer	617,010	302,066
Total	617,010	656,359
Unrecognized Losses
Less than 12 months	0	(110,523)
12 months or longer	(207,213)	(52,287)
Total	(207,213)	(162,810)
Mortgage-backed securities
Fair Value
Less than 12 months	0	367,849
12 months or longer	847,652	615,114
Total	847,652	982,963
Unrecognized Losses
Less than 12 months	0	(42,438)
12 months or longer	(195,933)	(81,416)
Total	(195,933)	(123,854)
States and political subdivisions
Fair Value
Less than 12 months	64,441	838,689
12 months or longer	864,668	135,573
Total	929,109	974,262
Unrecognized Losses
Less than 12 months	(4,877)	(127,355)
12 months or longer	(226,270)	(31,667)
Total	$ (231,147)	$ (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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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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