Loans and Allowance for Credit Losses (Composition of Nonaccrual Loans and Without an Allowance for Loan Loss by Portfolio Class) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	$ 55,523	$ 139,879
Nonaccrual without allowance for loan loss	9,245	25,127
Total Commercial [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	5,458	6,743
Nonaccrual without allowance for loan loss	5,207
Total Commercial [Member] | Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	844	2,486
Nonaccrual without allowance for loan loss		1,116
Residential Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	25,439	40,573
Nonaccrual without allowance for loan loss	1,997	1,705
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	11,887	23,385
Nonaccrual without allowance for loan loss	48
Total Commercial And Industrial [Member] | Total Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	11,895	66,692
Nonaccrual without allowance for loan loss	1,993	22,306
Total Commercial And Industrial [Member] | Total Commercial [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	6,974	52,836
Nonaccrual without allowance for loan loss	1,264	15,268
Total Commercial And Industrial [Member] | Total Commercial [Member] | Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Nonaccrual	4,921	13,856
Nonaccrual without allowance for loan loss	$ 729	$ 7,038