ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY INFORMATION - Analysis of Collateral Dependent and Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	$ 20,145	$ 12,597
Equipment and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	2,942	4,012
Commercial | Commercial and industrial | Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	5,037	4,199
Commercial | Commercial and industrial | Equipment and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	2,895	4,012
Commercial | Owner-occupied commercial | Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	497	811
Commercial | Owner-occupied commercial | Equipment and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	0	0
Commercial | Commercial mortgages | Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	3,616	2,070
Commercial | Commercial mortgages | Equipment and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	0	0
Commercial | Construction | Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	5,556	12
Commercial | Construction | Equipment and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	0	0
Residential | Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	3,175	3,125
Residential | Equipment and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	0	0
Consumer | Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	2,264	2,380
Consumer | Equipment and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost basis of nonaccruing collateral-dependent loans	$ 47	$ 0