Loans, Troubled Debt Restructurings Performing and Nonaccrual (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	$ 24,329	$ 53,263
Nonaccrual Restructured Loans(a)	16,293	26,292
Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	15,398	25,478
Nonaccrual Restructured Loans(a)	0	249
Commercial real estate — owner occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	1,912	2,080
Nonaccrual Restructured Loans(a)	0	0
Commercial real estate — investor
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	304	799
Nonaccrual Restructured Loans(a)	461	933
Real estate construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	227	311
Nonaccrual Restructured Loans(a)	182	198
Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	3,228	16,036
Nonaccrual Restructured Loans(a)	14,090	22,279
Carrying Amount Of Loans Sold	18,000
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	2,017	7,385
Nonaccrual Restructured Loans(a)	1,559	2,627
Carrying Amount Of Loans Sold	3,000
Other consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Performing Restructured Loans	1,243	1,174
Nonaccrual Restructured Loans(a)	1	$ 6
Pass | Total consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Carrying Amount Of Loans Sold	21,000
Nonaccrual | Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Carrying Amount Of Loans Sold	$ 7,000