LOANS HELD FOR INVESTMENT - Financial Effects of the Permanent Modifications Granted to Borrowers Experiencing Financial Difficulty (Details) - Permanent Modification [Member]	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Residential Portfolio Segment [Member] \| Conventional Residential Mortgage Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%	0.00%	0.00%
Weighted-Average Term Extension (in months)	108 months		73 months	69 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%	0.00%	1.80%
Weighted-Average Term Extension (in months)				106 months
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%	0.00%	0.00%
Weighted-Average Term Extension (in months)		208 months		208 months
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%	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%	0.00%	0.00%
Weighted-Average Term Extension (in months)				96 months
Change in Amortization Term			36 months
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%	0.00%	0.00%
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	14.50%	0.00%	13.82%
Weighted-Average Term Extension (in months)	80 months	178 months	87 months	178 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 (%)	0.00%	3.00%	0.50%	3.00%
Weighted-Average Term Extension (in months)		22 months	120 months	22 months
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%	0.00%	0.00%
Weighted-Average Term Extension (in months)	29 months	24 months	27 months	27 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 (%)	3.09%	3.04%	3.03%	2.62%
Weighted-Average Term Extension (in months)	21 months	26 months	20 months	29 months
Consumer Portfolio Segment [Member] \| Personal Loans [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	0.00%	0.00%	0.00%	0.00%
Weighted-Average Term Extension (in months)			22 months	25 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 (%)	4.59%	3.51%	4.57%	3.09%
Weighted-Average Term Extension (in months)	23 months	10 months	23 months	16 months
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	15.64%	17.48%	15.67%	17.21%
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%	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%	0.00%	0.00%
Weighted-Average Term Extension (in months)	30 months	26 months	28 months	25 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 (%)	0.00%	2.30%	3.01%	3.04%
Weighted-Average Term Extension (in months)		21 months	22 months	18 months

Change in amortization term of financing receivable modified for debtor experiencing financial difficulty.

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- 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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- Definition

Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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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.

+ References

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