LOANS HELD FOR INVESTMENT - Financial Effects of the Permanent Modifications Granted to Borrowers Experiencing Financial Difficulty (Details) - Permanent Modification [Member]	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 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)		236 months	66 months	236 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%	0.50%	0.00%	3.50%
Weighted-Average Term Extension (in months)		256 months		36 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%
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)	60 months	96 months	60 months	96 months
Change in Amortization Term	36 months		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%	0.00%	14.22%	13.00%
Weighted-Average Term Extension (in 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 (%)	0.50%	0.00%	0.50%	0.00%
Weighted-Average Term Extension (in months)	120 months		120 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)	22 months	21 months	24 months	26 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 (%)	3.55%	3.29%	2.91%	2.57%
Weighted-Average Term Extension (in months)	19 months	28 months	18 months	28 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		23 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 (%)	4.90%	2.99%	4.49%	3.44%
Weighted-Average Term Extension (in months)	22 months	19 months	22 months	17 months
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member]
Financing Receivable Modifications [Line Items]
Weighted-Average Interest Rate Reduction (%)	15.72%	17.55%	15.79%	17.11%
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)	31 months	26 months	27 months	24 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 (%)	2.97%	3.34%	3.25%	3.31%
Weighted-Average Term Extension (in months)	25 months	17 months	21 months	17 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
-Paragraph 12A
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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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