LOANS HELD FOR INVESTMENT - Financial Effects of the Permanent Modifications Granted to Borrowers Experiencing Financial Difficulty (Details) - Permanent Modification [Member]	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Residential Portfolio Segment [Member] \| Conventional Residential Mortgage Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Weighted-Average Term Extension (in months)		66 months
Residential Portfolio Segment [Member] \| Conventional Residential Mortgage Loans [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	15.27%	14.23%
Weighted-Average Term Extension (in months)	8 months	120 months
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	2.25%	0.00%
Weighted-Average Term Extension (in months)	12 months
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Weighted-Average Term Extension (in months)	27 months	25 months
Consumer Portfolio Segment [Member] \| Automobile Loan [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	4.04%	1.88%
Weighted-Average Term Extension (in months)	26 months	16 months
Consumer Portfolio Segment [Member] \| Personal Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Weighted-Average Term Extension (in months)		36 months
Consumer Portfolio Segment [Member] \| Personal Loans [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	4.79%	3.65%
Weighted-Average Term Extension (in months)	26 months	23 months
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	14.60%	16.01%
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%
Weighted-Average Term Extension (in months)	24 months	27 months
Consumer Portfolio Segment [Member] \| Other Loans [Member] \| Combination of Reduction in Interest Rate and Extension of Maturity [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	2.00%	3.14%
Weighted-Average Term Extension (in months)	20 months	21 months

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.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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