LOANS AND LEASES - Commercial Real Estate Loans (Details) - Loan Portfolio Diversification Risk [Member] - Commercial Real Estate Loans [Member]	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Owner-Occupied [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Percent of total loans and leases	28.20%	28.10%
Non-Owner-Occupied [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Percent of total loans and leases	71.80%	71.90%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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