Loans And Allowance for Credit Losses (Collateral-Dependent Loans) (Details) - Commercial Portfolio Segment [Member] $ in Thousands	Sep. 30, 2020 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Amortized Cost	$ 36,734
Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Business, Amortized Cost	36,734
Business Assets
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Amortized Cost	18,843
Business Assets | Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Business, Amortized Cost	18,843
Future Revenue Streams
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Amortized Cost	3,616
Future Revenue Streams | Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Business, Amortized Cost	3,616
Energy Service
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Amortized Cost	14,276
Energy Service | Business [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Collateral Dependent Loans, Business, Amortized Cost	$ 14,276