FAIR VALUE MEASUREMENTS - Unobservable Inputs Recurring (Details) uSDPerLoan in Thousands, $ in Thousands	Sep. 30, 2022 USD ($) uSDPerLoan	Dec. 31, 2021 USD ($) uSDPerLoan
Quantitative information about the significant unobservable inputs within Level 3
Trading security	$ 6,812	$ 8,354
Level 3 \| Recurring
Quantitative information about the significant unobservable inputs within Level 3
Trading security	6,812	8,354
AFS Securities	3,920
Loans held for investment	1,049	1,200
Total	13,829	15,808
Level 3 \| Recurring \| Commitments to lend
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset	15	124
Level 3 \| Recurring \| Forward commitments
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset	7	134
Level 3 \| Recurring \| Capitalized servicing rights
Quantitative information about the significant unobservable inputs within Level 3
Capitalized servicing rights	$ 2,026	$ 1,966
Level 3 \| Recurring \| Discounted Cash Flow \| Discount Rate
Quantitative information about the significant unobservable inputs within Level 3
Trading security, Significant Unobservable Input Value	0.0638	0.0335
Loan held for investment, Significant Unobservable Input Value	0.2500	0.2500
Level 3 \| Recurring \| Discounted Cash Flow \| Discount Rate \| Capitalized servicing rights
Quantitative information about the significant unobservable inputs within Level 3
Capitalized servicing rights, Significant Unobservable Input Value	0.0955	0.0950
Level 3 \| Recurring \| Discounted Cash Flow \| Collateral Value \| Minimum
Quantitative information about the significant unobservable inputs within Level 3
Loan held for investment, Significant Unobservable Input Value	0	6,300,000
Level 3 \| Recurring \| Discounted Cash Flow \| Collateral Value \| Maximum
Quantitative information about the significant unobservable inputs within Level 3
Loan held for investment, Significant Unobservable Input Value	20,700,000	19,800,000
Level 3 \| Recurring \| Discounted Cash Flow \| Constant Prepayment Rate (CPR) \| Capitalized servicing rights
Quantitative information about the significant unobservable inputs within Level 3
Capitalized servicing rights, Significant Unobservable Input Value	0.1248	0.1941
Level 3 \| Recurring \| Indication from Market Maker \| Price
Quantitative information about the significant unobservable inputs within Level 3
AFS Securities, Significant Unobservable Input Value	0.9800	1.0100
Level 3 \| Recurring \| Historical Trend \| Closing Ratio \| Commitments to lend
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset, Significant Unobservable Input Value	0.8395	0.8209
Level 3 \| Recurring \| Historical Trend \| Closing Ratio \| Forward commitments
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset, Significant Unobservable Input Value	0.8395	0.8209
Level 3 \| Recurring \| Pricing Model \| Origination Costs, per loan \| Commitments to lend
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset, Significant Unobservable Input Value \| uSDPerLoan	3	3
Level 3 \| Recurring \| Pricing Model \| Origination Costs, per loan \| Forward commitments
Quantitative information about the significant unobservable inputs within Level 3
Derivative asset, Significant Unobservable Input Value \| uSDPerLoan	3	3

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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