INVESTMENT SECURITIES - Summary of Investments in Debt and Equity Securities Reported in the Financial Statements at an Amount Less Than Their Historical Cost (Details) - Investments reported at less than historical cost - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Schedule of Investments [Line Items]
Historical cost	$ 1,527,184	$ 1,592,597
Fair value	1,285,896	1,353,744
Gross unrealized losses	$ 241,288	$ 238,853
Percentage of the Corporation's investment securities available for sale in an unrealized loss position	94.70%	97.60%

INVESTMENT SECURITIES - Summary of Investments in Debt and Equity Securities Reported in the Financial Statements at an Amount Less Than Their Historical Cost (Details) - Investments reported at less than historical cost - USD ($)
$ in Thousands

Jun. 30, 2025

Dec. 31, 2024

Schedule of Investments [Line Items]

Historical cost

$ 1,527,184

$ 1,592,597

Fair value

1,285,896

1,353,744

Gross unrealized losses

$ 241,288

$ 238,853

Percentage of the Corporation's investment securities available for sale in an unrealized loss position

94.70%

97.60%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details