Investment Securities - Held-to-Maturity with Unrecognized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Fair Value
Less than 12 months	$ 52,126	$ 37,007
12 months or longer	2,451,226	2,402,361
Total	2,503,352	2,439,368
Unrecognized Losses
Less than 12 months	(789)	(430)
12 months or longer	(390,936)	(483,630)
Total	(391,725)	(484,060)
U.S. government-sponsored entities and agencies
Fair Value
Less than 12 months	0	0
12 months or longer	705,894	664,331
Total	705,894	664,331
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(132,641)	(168,653)
Total	(132,641)	(168,653)
Mortgage-backed securities
Fair Value
Less than 12 months	0	0
12 months or longer	794,313	800,666
Total	794,313	800,666
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(130,879)	(169,546)
Total	(130,879)	(169,546)
States and political subdivisions
Fair Value
Less than 12 months	52,126	37,007
12 months or longer	951,019	937,364
Total	1,003,145	974,371
Unrecognized Losses
Less than 12 months	(789)	(430)
12 months or longer	(127,416)	(145,431)
Total	$ (128,205)	$ (145,861)

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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