Investment Securities - Held-to-Maturity with Unrecognized Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value
Less than 12 months	$ 25,998	$ 0
12 months or longer	2,443,259	2,530,274
Total	2,469,257	2,530,274
Unrecognized Losses
Less than 12 months	(231)	0
12 months or longer	(474,185)	(414,105)
Total	(474,416)	(414,105)
U.S. government-sponsored entities and agencies
Fair Value
Less than 12 months	0	0
12 months or longer	662,331	671,126
Total	662,331	671,126
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(167,071)	(154,827)
Total	(167,071)	(154,827)
Mortgage-backed securities
Fair Value
Less than 12 months	0	0
12 months or longer	838,289	881,994
Total	838,289	881,994
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(163,626)	(147,137)
Total	(163,626)	(147,137)
States and political subdivisions
Fair Value
Less than 12 months	25,998	0
12 months or longer	942,639	977,154
Total	968,637	977,154
Unrecognized Losses
Less than 12 months	(231)	0
12 months or longer	(143,488)	(112,141)
Total	$ (143,719)	$ (112,141)

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
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
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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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