FAIR VALUE MEASUREMENT - Schedule of Fair Value Hierarchy Measurement (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Assets:
Investment securities AFS	$ 1,002,522,000	$ 1,072,093,000
Single family mortgage servicing rights	61,584,000
Derivative assets	9,280,000	27,639,000
Liabilities:
Derivative liabilities	1,263,000	2,785,000
Residential Mortgage Backed Securities
Assets:
Investment securities AFS	32,963,000	51,046,000
Commercial Mortgage Backed Securities
Assets:
Investment securities AFS	62,792,000	45,184,000
Municipal bonds
Assets:
Investment securities AFS	539,923,000	564,703,000
Corporate debt securities
Assets:
Investment securities AFS	19,616,000	15,222,000
Agency debentures
Assets:
Investment securities AFS		1,846,000
Fair Value, Recurring
Assets:
Single family LHFS	128,041,000	194,643,000
Single family LHFI	7,287,000	7,108,000
Single family mortgage servicing rights	61,584,000	49,966,000
Total assets	1,207,359,000	1,359,699,000
Liabilities:
Total Liabilities	5,184,000	24,232,000
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	334,000	0
Liabilities:
Total Liabilities	0	4,000
Fair Value, Recurring \| Level 2
Assets:
Single family LHFS	128,041,000	194,643,000
Single family LHFI	0	0
Single family mortgage servicing rights	0	0
Total assets	1,133,185,000	1,282,520,000
Liabilities:
Total Liabilities	5,181,000	24,225,000
Fair Value, Recurring \| Level 3
Assets:
Investment securities AFS	2,482,000	2,710,000
Single family LHFS	0	0
Single family LHFI	7,287,000	7,108,000
Single family mortgage servicing rights	61,584,000	49,966,000
Total assets	73,840,000	77,179,000
Liabilities:
Total Liabilities	3,000	3,000
Fair Value, Recurring \| Residential Mortgage Backed Securities
Assets:
Investment securities AFS	32,963,000	51,046,000
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	30,556,000	48,417,000
Fair Value, Recurring \| Residential Mortgage Backed Securities \| Level 3
Assets:
Investment securities AFS	2,407,000	2,629,000
Fair Value, Recurring \| Commercial Mortgage Backed Securities
Assets:
Investment securities AFS	62,792,000	45,184,000
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	62,792,000	45,184,000
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	187,394,000	234,909,000
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	187,394,000	234,909,000
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	136,659,000	159,183,000
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	136,659,000	159,183,000
Fair Value, Recurring \| Commercial Collateralized Mortgage Obligations \| Level 3
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Municipal bonds
Assets:
Investment securities AFS	539,923,000	564,703,000
Fair Value, Recurring \| Municipal bonds \| Level 1
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Municipal bonds \| Level 2
Assets:
Investment securities AFS	539,923,000	564,703,000
Fair Value, Recurring \| Municipal bonds \| Level 3
Assets:
Investment securities AFS	0	0
Fair Value, Recurring \| Corporate debt securities
Assets:
Investment securities AFS	19,616,000	15,222,000
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	19,541,000	15,141,000
Fair Value, Recurring \| Corporate debt securities \| Level 3
Assets:
Investment securities AFS	75,000	81,000
Fair Value, Recurring \| U.S. Treasury securities
Assets:
Investment securities AFS	23,175,000
Fair Value, Recurring \| U.S. Treasury securities \| Level 1
Assets:
Investment securities AFS	0
Fair Value, Recurring \| U.S. Treasury securities \| Level 2
Assets:
Investment securities AFS	23,175,000
Fair Value, Recurring \| U.S. Treasury securities \| Level 3
Assets:
Investment securities AFS	0
Fair Value, Recurring \| Agency debentures
Assets:
Investment securities AFS		1,846,000
Fair Value, Recurring \| Agency debentures \| Level 1
Assets:
Investment securities AFS		0
Fair Value, Recurring \| Agency debentures \| Level 2
Assets:
Investment securities AFS		1,846,000
Fair Value, Recurring \| Agency debentures \| Level 3
Assets:
Investment securities AFS		0
Fair Value, Recurring \| Futures
Assets:
Derivative assets	334,000
Liabilities:
Derivative liabilities		4,000
Fair Value, Recurring \| Futures \| Level 1
Assets:
Derivative assets	334,000
Liabilities:
Derivative liabilities		4,000
Fair Value, Recurring \| Futures \| Level 2
Liabilities:
Derivative liabilities	0	0
Fair Value, Recurring \| Futures \| Level 3
Assets:
Derivative assets	0
Liabilities:
Derivative liabilities		0
Fair Value, Recurring \| Forward sale commitments
Assets:
Derivative assets	723,000	1,035,000
Liabilities:
Derivative liabilities	640,000	3,714,000
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	723,000	1,035,000
Liabilities:
Derivative liabilities	640,000	3,714,000
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	2,487,000	17,395,000
Liabilities:
Derivative liabilities	3,000	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	2,487,000	17,395,000
Liabilities:
Derivative liabilities	3,000	3,000
Fair Value, Recurring \| Interest rate swaps
Assets:
Derivative assets	4,381,000	17,459,000
Liabilities:
Derivative liabilities	4,541,000	20,511,000
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	4,381,000	17,459,000
Liabilities:
Derivative liabilities	4,541,000	20,511,000
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 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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