FAIR VALUE MEASUREMENT - Schedule of Fair Value Hierarchy Measurement (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Assets:
Single family mortgage servicing rights	$ 76,617,000
Fair Value, Recurring
Assets:
Single family LHFS	14,075,000	$ 128,041,000
Single family LHFI	5,868,000	7,287,000
Single family mortgage servicing rights	76,617,000	61,584,000
Total assets	1,508,094,000	1,207,359,000
Liabilities:
Total liabilities	13,280,000	5,184,000
Fair Value, Recurring \| Level 1
Assets:
Single family LHFS	0	0
Single family LHFI	0	0
Single family mortgage servicing rights	0	0
Total assets	19,233,000	334,000
Liabilities:
Total liabilities	0	0
Fair Value, Recurring \| Level 2
Assets:
Single family LHFS	14,075,000	128,041,000
Single family LHFI	0	0
Single family mortgage servicing rights	0	0
Total assets	1,404,226,000	1,133,185,000
Liabilities:
Total liabilities	13,244,000	5,181,000
Fair Value, Recurring \| Level 3
Assets:
Investment securities AFS	2,009,000	2,482,000
Single family LHFS	0	0
Single family LHFI	5,868,000	7,287,000
Single family mortgage servicing rights	76,617,000	61,584,000
Total assets	84,635,000	73,840,000
Liabilities:
Total liabilities	36,000	3,000
Fair Value, Recurring \| U.S. Treasury securities
Assets:
Trading securities - U.S. Treasury securities	18,997,000
Fair Value, Recurring \| U.S. Treasury securities \| Level 1
Assets:
Trading securities - U.S. Treasury securities	18,997,000
Fair Value, Recurring \| U.S. Treasury securities \| Level 2
Assets:
Trading securities - U.S. Treasury securities	0
Fair Value, Recurring \| U.S. Treasury securities \| Level 3
Assets:
Trading securities - U.S. Treasury securities	0
Fair Value, Recurring \| Residential Mortgage Backed Securities
Assets:
Investment securities AFS	197,262,000	32,963,000
Fair Value, Recurring \| Residential Mortgage Backed Securities \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Residential Mortgage Backed Securities \| Level 2
Assets:
Investment securities AFS	195,321,000	30,556,000
Fair Value, Recurring \| Residential Mortgage Backed Securities \| Level 3
Assets:
Investment securities AFS	1,941,000	2,407,000
Fair Value, Recurring \| Commercial Mortgage Backed Securities
Assets:
Investment securities AFS	56,049,000	62,792,000
Fair Value, Recurring \| Commercial Mortgage Backed Securities \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Commercial Mortgage Backed Securities \| Level 2
Assets:
Investment securities AFS	56,049,000	62,792,000
Fair Value, Recurring \| Commercial Mortgage Backed Securities \| Level 3
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Residential Collateralized Mortgage Obligations
Assets:
Investment securities AFS	553,039,000	187,394,000
Fair Value, Recurring \| Residential Collateralized Mortgage Obligations \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Residential Collateralized Mortgage Obligations \| Level 2
Assets:
Investment securities AFS	553,039,000	187,394,000
Fair Value, Recurring \| Residential Collateralized Mortgage Obligations \| Level 3
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Commercial Collateralized Mortgage Obligations
Assets:
Investment securities AFS	70,519,000	136,659,000
Fair Value, Recurring \| Commercial Collateralized Mortgage Obligations \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Commercial Collateralized Mortgage Obligations \| Level 2
Assets:
Investment securities AFS	70,519,000	136,659,000
Fair Value, Recurring \| Commercial Collateralized Mortgage Obligations \| Level 3
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Municipal bonds
Assets:
Investment securities AFS	411,548,000	539,923,000
Fair Value, Recurring \| Municipal bonds \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Municipal bonds \| Level 2
Assets:
Investment securities AFS	411,548,000	539,923,000
Fair Value, Recurring \| Municipal bonds \| Level 3
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Corporate debt securities
Assets:
Investment securities AFS	42,945,000	19,616,000
Fair Value, Recurring \| Corporate debt securities \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Corporate debt securities \| Level 2
Assets:
Investment securities AFS	42,877,000	19,541,000
Fair Value, Recurring \| Corporate debt securities \| Level 3
Assets:
Investment securities AFS	68,000	75,000
Fair Value, Recurring \| U.S. Treasury securities
Assets:
Investment securities AFS	19,934,000	23,175,000
Fair Value, Recurring \| U.S. Treasury securities \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| U.S. Treasury securities \| Level 2
Assets:
Investment securities AFS	19,934,000	23,175,000
Fair Value, Recurring \| U.S. Treasury securities \| Level 3
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Agency debentures
Assets:
Investment securities AFS	27,478,000
Fair Value, Recurring \| Agency debentures \| Level 1
Assets:
Investment securities AFS	0
Fair Value, Recurring \| Agency debentures \| Level 2
Assets:
Investment securities AFS	27,478,000
Fair Value, Recurring \| Agency debentures \| Level 3
Assets:
Investment securities AFS	0
Fair Value, Recurring \| Futures
Assets:
Derivative assets	18,000	334,000
Fair Value, Recurring \| Futures \| Level 1
Assets:
Derivative assets	18,000	334,000
Fair Value, Recurring \| Futures \| Level 2
Assets:
Derivative assets	0	0
Fair Value, Recurring \| Futures \| Level 3
Assets:
Derivative assets	0	0
Fair Value, Recurring \| Options
Assets:
Derivative assets	218,000
Fair Value, Recurring \| Options \| Level 1
Assets:
Derivative assets	218,000
Fair Value, Recurring \| Options \| Level 2
Assets:
Derivative assets	0
Fair Value, Recurring \| Options \| Level 3
Assets:
Derivative assets
Fair Value, Recurring \| Forward sale commitments
Assets:
Derivative assets	293,000	723,000
Liabilities:
Derivative liabilities	151,000	640,000
Fair Value, Recurring \| Forward sale commitments \| Level 1
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring \| Forward sale commitments \| Level 2
Assets:
Derivative assets	293,000	723,000
Liabilities:
Derivative liabilities	151,000	640,000
Fair Value, Recurring \| Forward sale commitments \| Level 3
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring \| Interest rate lock commitments
Assets:
Derivative assets	141,000	2,487,000
Liabilities:
Derivative liabilities	36,000	3,000
Fair Value, Recurring \| Interest rate lock commitments \| Level 1
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring \| Interest rate lock commitments \| Level 2
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring \| Interest rate lock commitments \| Level 3
Assets:
Derivative assets	141,000	2,487,000
Liabilities:
Derivative liabilities	36,000	3,000
Fair Value, Recurring \| Interest rate swaps
Assets:
Derivative assets	13,093,000	4,381,000
Liabilities:
Derivative liabilities	13,093,000	4,541,000
Fair Value, Recurring \| Interest rate swaps \| Level 1
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring \| Interest rate swaps \| Level 2
Assets:
Derivative assets	13,093,000	4,381,000
Liabilities:
Derivative liabilities	13,093,000	4,541,000
Fair Value, Recurring \| Interest rate swaps \| Level 3
Assets:
Derivative assets	0	0
Liabilities:
Derivative liabilities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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Fair value of financial and nonfinancial obligations.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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