LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES - LOANS - Narrative (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022 USD ($) segment item division	Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loan portfolio segments | segment	3
Number of warehouse lending divisions | division	2
Loans that qualify as collateral for FHLB advances	$ 718,600	$ 761,600
Loans that qualify as collateral for Federal Reserve Bank lines of credit	$ 491,400	428,700
Minimum term for accrual of interest on loans to be discontinued	90 days
Unamortized costs and premiums	$ 5,800	4,900
Net discounts on acquired loans	568	751
Accrued interest receivable	$ 7,200	$ 6,300
Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Units in Real Estate Property | item	5