Investment Securities - Held-to-Maturity with Unrecognized Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value
Less than 12 months	$ 19,953	$ 0
12 months or longer	2,477,754	2,530,274
Total	2,497,707	2,530,274
Unrecognized Losses
Less than 12 months	(100)	0
12 months or longer	(454,537)	(414,105)
Total	(454,637)	(414,105)
U.S. government-sponsored entities and agencies
Fair Value
Less than 12 months	0	0
12 months or longer	662,735	671,126
Total	662,735	671,126
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(164,949)	(154,827)
Total	(164,949)	(154,827)
Mortgage-backed securities
Fair Value
Less than 12 months	0	0
12 months or longer	857,657	881,994
Total	857,657	881,994
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(159,201)	(147,137)
Total	(159,201)	(147,137)
States and political subdivisions
Fair Value
Less than 12 months	19,953	0
12 months or longer	957,362	977,154
Total	977,315	977,154
Unrecognized Losses
Less than 12 months	(100)	0
12 months or longer	(130,387)	(112,141)
Total	$ (130,487)	$ (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
-Publisher FASB
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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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