LOANS - Narrative (Details) - USD ($)	6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income on nonaccrual loans	$ 0
Nonaccrual loans	77,745,000		$ 75,124,000
Loans modified that are not troubled debt restructurings	139,600,000	$ 107,700,000
COVID-19 Deferrals	2,757,701,000
Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring	42,300,000		35,200,000
Troubled debt restructurings, previous charge-offs, excluding purchased loans	1,700,000		1,900,000
Allowance for loan losses allocated to troubled debt restructuring	2,900,000		3,700,000
Troubled debt restructurings principal balances	11,278,000	5,268,000
Financing receivable, modifications, subsequent default, recorded investment	1,700,000	1,900,000
Minimum | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	100,000	100,000	100,000
Troubled debt restructuring loans	100,000	$ 100,000	$ 100,000
Real estate, equipment and receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Collateral-dependent Loans	$ 102,100,000