Loans and Allowance For Credit Losses (Narrative) (Details)	12 Months Ended
	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Days Loan Customer May Apply for a Deferral of Payments Due to COVID-19	90 days
Number of Loans in COVID-19 Deferment | loan	42
Outstanding Balance of COVID-19 Loans in Deferment	$ 79,300,000
Number of Days Past Due When Loans are Placed on Nonaccrual Status	90 days
Troubled debt restructurings included in impaired loans	$ 24,500,000	$ 25,700,000
Current Troubled debt restructurings included in impaired loans	20,500,000	22,900,000
Commitments to Lend Funds for Restructured Loans	0
Financing Receivable, Troubled Debt Restructuring, Individually Evaluated for Impairment, Minimum	$ 500,000
Threshold Period Past Due for Loans to be Default	30 days
Loan review aggregate exposure amount on non-homogenous commercial loan relationships	$ 5,000,000.0
Loans Collectively Evaluated Fully Guaranteed or Cash Secured Loans	83,900,000
Concentrations of Loans to any Single Industry in Excess of Ten Percent of Total Loans	0	0
Threshold for related party loans	60,000
Accrued Interest Receivable and Fees on Loans	9,100,000	$ 6,500,000
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family rental small loan / large loan classification	600,000
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family rental small loan / large loan classification	$ 600,000