LOANS - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Financing Receivable, Recorded Investment [Line Items]
Accrued interest receivable for LHFI totaled with no related ACL		$ 17,900		$ 17,900
Interest income not recorded due to loans in non-accrual status					$ 758
Non- Accrual	$ 0	0		0		$ 0
TDR Period Increase (Decrease), Allowance for Loan and Lease Losses		21	$ 11	21	49
Allowance for Loan and Lease Losses Write-offs, Net				0		0
TDRs for increased allowance for credit losses for which there was a payment default within twelve months				238	2,400
Total loans, other financial institutions		118,000		118,000
Loans sold to other financial institutions.		71,500		71,500
Loan retained in other financial institutions.		46,500		46,500
PPP Loans	239,700	157,800		157,800		239,700
Provision for Loan and Lease Losses		0	$ 7,606	0	$ 14,708
Amortized cost, PCD loans		11,800		11,800
PCD loans, estimated ACL		1,300		1,300
Trouble debt restructuring
Financing Receivable, Recorded Investment [Line Items]
TDRs total	$ 27,500			21,500
Additional amount committed on TDR loans		$ 0		0
TDRs allowance for loan losses				$ 3,000		$ 4,100