Allowance for Loan and Lease Losses and Credit Quality - Summary of Defaulted TDR Loans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Defaulted TDR loan balance modified during the period	$ 746	$ 1,258	$ 3,144	$ 8,725
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Defaulted TDR loan balance modified during the period	0	87	297	4,784
Commercial | Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Defaulted TDR loan balance modified during the period	0	87	297	4,784
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Defaulted TDR loan balance modified during the period	746	1,171	2,847	3,941
Consumer | Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Defaulted TDR loan balance modified during the period	212	778	964	2,556
Consumer | Consumer installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Defaulted TDR loan balance modified during the period	452	217	1,555	950
Consumer | Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Defaulted TDR loan balance modified during the period	$ 82	$ 176	$ 328	$ 435