LOANS, Carrying Amounts of Loans Purchased and Sold (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020 USD ($)
Carrying Amounts of Loans Purchased and Sold
Purchases	$ 339,563
Sales	37,409
Commercial Portfolio Segment [Member] | Business Lending [Member]
Carrying Amounts of Loans Purchased and Sold
Purchases	253,368
Sales	0
Residential Portfolio Segment [Member] | Consumer Mortgage [Member]
Carrying Amounts of Loans Purchased and Sold
Purchases	26,721
Sales	37,409
Consumer Portfolio Segment [Member] | Consumer Indirect [Member]
Carrying Amounts of Loans Purchased and Sold
Purchases	13,926
Sales	0
Consumer Portfolio Segment [Member] | Consumer Direct [Member]
Carrying Amounts of Loans Purchased and Sold
Purchases	5,994
Sales	0
Consumer Portfolio Segment [Member] | Home Equity [Member]
Carrying Amounts of Loans Purchased and Sold
Purchases	39,554
Sales	$ 0