FAIR VALUE MEASUREMENTS - Schedule of Quantitative Information about the Significant Unobservable Inputs within Level 3 (Details) $ in Thousands	Mar. 31, 2023 USD ($) uSDPerLoan	Dec. 31, 2022 USD ($) uSDPerLoan
Quantitative information about the significant unobservable inputs within Level 3
Trading Securities	$ 6,584	$ 6,708
Level 3 \| Recurring
Quantitative information about the significant unobservable inputs within Level 3
Trading Securities	6,584	6,708
AFS Securities	3,800
Loans held for investment	460	605
Total	12,551	13,184
Level 3 \| Recurring \| Commitments to lend
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset	26	17
Level 3 \| Recurring \| Forward commitments
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset	15	8
Level 3 \| Recurring \| Capitalized servicing rights
Quantitative information about the significant unobservable inputs within Level 3
Capitalized servicing rights	$ 1,666	$ 1,846
Level 3 \| Recurring \| Discount Rate \| Discounted Cash Flow
Quantitative information about the significant unobservable inputs within Level 3
Trading security, significant unobservable input value	0.0547	0.0592
Loan held for investment, Significant Unobservable Input Value	0.2500	0.2500
Level 3 \| Recurring \| Discount Rate \| Discounted Cash Flow \| Capitalized servicing rights
Quantitative information about the significant unobservable inputs within Level 3
Capitalized Servicing Rights, Significant Unobservable Input Value	0.0956	0.0956
Level 3 \| Recurring \| Price \| Indication from Market Maker
Quantitative information about the significant unobservable inputs within Level 3
AFS Securities, Significant Unobservable Input Value	0.9500	1.0100
Level 3 \| Recurring \| Collateral Value \| Discounted Cash Flow \| Minimum
Quantitative information about the significant unobservable inputs within Level 3
Loan held for investment, Significant Unobservable Input Value	0.0	0.0
Level 3 \| Recurring \| Collateral Value \| Discounted Cash Flow \| Maximum
Quantitative information about the significant unobservable inputs within Level 3
Loan held for investment, Significant Unobservable Input Value	20,300,000	20,400,000
Level 3 \| Recurring \| Closing Ratio \| Historical Trend \| Commitments to lend
Quantitative information about the significant unobservable inputs within Level 3
Commitments, Significant Unobservable Input Value	0.8043	0.8063
Level 3 \| Recurring \| Closing Ratio \| Historical Trend \| Forward commitments
Quantitative information about the significant unobservable inputs within Level 3
Commitments, Significant Unobservable Input Value	0.8043	0.8063
Level 3 \| Recurring \| Origination Costs, per loan \| Pricing Model \| Commitments to lend
Quantitative information about the significant unobservable inputs within Level 3
Commitments, Significant Unobservable Input Value \| uSDPerLoan	2,000	2,000
Level 3 \| Recurring \| Origination Costs, per loan \| Pricing Model \| Forward commitments
Quantitative information about the significant unobservable inputs within Level 3
Commitments, Significant Unobservable Input Value \| uSDPerLoan	2,000	2,000
Level 3 \| Recurring \| Constant Prepayment Rate (CPR) \| Discounted Cash Flow \| Capitalized servicing rights
Quantitative information about the significant unobservable inputs within Level 3
Capitalized Servicing Rights, Significant Unobservable Input Value	0.1115	0.1107

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