INVESTMENT SECURITIES - Schedule of Held-to-Maturity with Unrecognized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Fair Value
Less than 12 months	$ 77,487	$ 0
12 months or longer	2,186,560	2,489,058
Total	2,264,047	2,489,058
Unrecognized Losses
Less than 12 months	(9,434)	0
12 months or longer	(549,596)	(356,103)
Total	(559,030)	(356,103)
U.S. government-sponsored entities and agencies
Fair Value
Less than 12 months	0	0
12 months or longer	646,493	710,909
Total	646,493	710,909
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(180,529)	(129,526)
Total	(180,529)	(129,526)
Mortgage-backed securities - Agency
Fair Value
Less than 12 months	0	0
12 months or longer	690,914	782,818
Total	690,914	782,818
Unrecognized Losses
Less than 12 months	0	0
12 months or longer	(168,520)	(127,505)
Total	(168,520)	(127,505)
States and political subdivisions
Fair Value
Less than 12 months	77,487	0
12 months or longer	849,153	995,331
Total	926,640	995,331
Unrecognized Losses
Less than 12 months	(9,434)	0
12 months or longer	(200,547)	(99,072)
Total	$ (209,981)	$ (99,072)

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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