Allowance for Credit Losses - Amortized Cost Basis of Revolving Loans that Were Converted to Term Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020
Credit quality
Total Revolving Loans Converted to Term Loans During the Period	$ 4,222	$ 32,746
Commercial and Industrial
Credit quality
Total Revolving Loans Converted to Term Loans During the Period	294	28,522
Home equity Line
Credit quality
Total Revolving Loans Converted to Term Loans During the Period	$ 3,928	3,928
Residential Mortgage.
Credit quality
Total Revolving Loans Converted to Term Loans During the Period		$ 296