Loans and Leases - Concessions Granted on Accruing and Nonaccrual Loans Restructured (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan	Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan
Accrual Troubled Debt Restructuring Loans [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan	0	0	0	3
Financing Receivable Modifications Recorded Investments | $	$ 0	$ 0	$ 0	$ 9,206
Accrual Troubled Debt Restructuring Loans [Member] | Extended Maturity [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan	0	0	0	0
Financing Receivable Modifications Recorded Investments | $	$ 0	$ 0	$ 0	$ 0
Accrual Troubled Debt Restructuring Loans [Member] | Amortization Period Extension [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan	0	0	0	3
Financing Receivable Modifications Recorded Investments | $	$ 0	$ 0	$ 0	$ 9,206
Nonaccrual Troubled Debt Restructuring Loans [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan	0	0	1	1
Financing Receivable Modifications Recorded Investments | $	$ 0	$ 0	$ 66	$ 328
Nonaccrual Troubled Debt Restructuring Loans [Member] | Extended Maturity [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan	0	0	0	1
Financing Receivable Modifications Recorded Investments | $	$ 0	$ 0	$ 0	$ 328
Nonaccrual Troubled Debt Restructuring Loans [Member] | Amortization Period Extension [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan	0	0	1	0
Financing Receivable Modifications Recorded Investments | $	$ 0	$ 0	$ 66	$ 0
Real Estate-Commercial [Member] | Accrual Troubled Debt Restructuring Loans [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan			0	3
Financing Receivable Modifications Recorded Investments | $				$ 9,206
Real Estate-Commercial [Member] | Accrual Troubled Debt Restructuring Loans [Member] | Extended Maturity [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan				0
Financing Receivable Modifications Recorded Investments | $				$ 0
Real Estate-Commercial [Member] | Accrual Troubled Debt Restructuring Loans [Member] | Amortization Period Extension [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan				3
Financing Receivable Modifications Recorded Investments | $				$ 9,206
Real Estate-Commercial [Member] | Nonaccrual Troubled Debt Restructuring Loans [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan			0	1
Financing Receivable Modifications Recorded Investments | $				$ 328
Real Estate-Commercial [Member] | Nonaccrual Troubled Debt Restructuring Loans [Member] | Extended Maturity [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan				1
Financing Receivable Modifications Recorded Investments | $				$ 328
Real Estate-Commercial [Member] | Nonaccrual Troubled Debt Restructuring Loans [Member] | Amortization Period Extension [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan				0
Financing Receivable Modifications Recorded Investments | $				$ 0
Real Estate Residential Secured For Personal Purpose [Member] | Nonaccrual Troubled Debt Restructuring Loans [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan			1	0
Financing Receivable Modifications Recorded Investments | $			$ 66
Real Estate Residential Secured For Personal Purpose [Member] | Nonaccrual Troubled Debt Restructuring Loans [Member] | Extended Maturity [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan			0
Financing Receivable Modifications Recorded Investments | $			$ 0
Real Estate Residential Secured For Personal Purpose [Member] | Nonaccrual Troubled Debt Restructuring Loans [Member] | Amortization Period Extension [Member]
Concessions granted on accruing and non-accrual loans restructured
No. of Loans | loan			1
Financing Receivable Modifications Recorded Investments | $			$ 66