LOANS (Troubled-Amortized Cost Basis Debt Restructuring Loan Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 423	$ 545
Combination of Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	261	0
Commercial loans \| Other commercial and industrial \| Domestic - Puerto Rico \| Combination of Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 89	$ 0
Percentage of total class of financing receivable.	0.01%	0.00%
Commercial loans \| Commercial US \| Principal Forbearance / Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.		$ 4,425
Percentage of total class of financing receivable.		0.61%
Commercial loans \| Commercial US \| Combination of Term Extension and Principal Forgiveness/Forbearance
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 0	$ 3,404
Percentage of total class of financing receivable.	0.00%	0.47%
Commercial loans \| Commercial US \| Combination of Interest Rate Reduction, Term Extension and Principal Forgiveness / Forbearance
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 0	$ 3,407
Percentage of total class of financing receivable.	0.00%	0.47%
Commercial loans \| Commercial US \| US – Federal \| Principal Forbearance / Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 0
Percentage of total class of financing receivable.	0.00%
Mortgage loans \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 354	$ 545
Percentage of total class of financing receivable.	0.03%	0.04%
Personal loans \| Personal loans \| Combination of Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 24	$ 0
Percentage of total class of financing receivable.	0.00%	0.00%
Auto loans \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 69	$ 0
Percentage of total class of financing receivable.	0.00%	0.00%
Auto loans \| Combination of Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis.	$ 148	$ 0
Percentage of total class of financing receivable.	0.01%	0.00%

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

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