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INVESTMENT SECURITIES - Investments in Debt and Equity Securities Reported Less than Historical Cost (Details) - Investments reported at less than historical cost - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Schedule of Investments [Line Items]
Historical cost	$ 1,592,597	$ 1,781,108
Fair value	1,353,744	1,560,554
Gross unrealized losses	$ 238,853	$ 220,554
Percent of the Corporation's investments available for sale in an unrealized loss position	97.60%	95.90%

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