Loans and Leases and Allowance for Credit Losses - Loans modified under terms of TDR (Details) - Loans Receivable $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	64	78	94
Pre-Modification Outstanding Recorded Investment	$ 7,971	$ 7,168	$ 9,347
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 7,798	$ 6,506	$ 9,172
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	6	4	4
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 2,205	$ 852	$ 371
Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	236	40	2,089
Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	6,858	4,611	5,930
Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 704	$ 1,855	$ 1,153
Home equity lines of credit
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	1	1
Pre-Modification Outstanding Recorded Investment	$ 42	$ 296	$ 38
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 41	$ 176	$ 38
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	0	0	0
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 0
Home equity lines of credit | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	38
Home equity lines of credit | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Home equity lines of credit | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 41	$ 176	$ 0
Indirect auto
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	35	34	35
Pre-Modification Outstanding Recorded Investment	$ 643	$ 786	$ 966
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 643	$ 786	$ 966
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	0	0	0
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 0
Indirect auto | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Indirect auto | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Indirect auto | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 643	$ 786	$ 966
Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	9	14	17
Pre-Modification Outstanding Recorded Investment	$ 5,299	$ 3,761	$ 4,426
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 5,162	$ 3,228	$ 4,426
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	5	0	3
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 2,104	$ 0	$ 286
Commercial | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	106	0	0
Commercial | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	5,056	2,335	4,361
Commercial | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 893	$ 65
Commercial | Owner occupied commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	5	6	8
Pre-Modification Outstanding Recorded Investment	$ 1,438	$ 2,603	$ 2,699
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 1,387	$ 2,269	$ 2,699
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	3	0	1
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 1,869	$ 0	$ 252
Commercial | Owner occupied commercial real estate | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Owner occupied commercial real estate | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	1,387	2,161	2,699
Commercial | Owner occupied commercial real estate | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 108	$ 0
Commercial | Income producing commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	2	2	1
Pre-Modification Outstanding Recorded Investment	$ 3,753	$ 257	$ 257
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 3,743	$ 252	$ 257
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	0	0	0
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 0
Commercial | Income producing commercial real estate | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	106	0	0
Commercial | Income producing commercial real estate | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	3,637	0	257
Commercial | Income producing commercial real estate | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 252	$ 0
Commercial | Construction
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0	0	3
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 458
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 0	$ 458
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	1	0	0
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 3	$ 0	$ 0
Commercial | Construction | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Construction | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	393
Commercial | Construction | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 0	$ 65
Commercial | Equipment financing
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 0	$ 0
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	0	0	0
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 0
Commercial | Equipment financing | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Equipment financing | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Equipment financing | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 0	$ 0
Commercial | Commercial & industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	2	6	5
Pre-Modification Outstanding Recorded Investment	$ 108	$ 901	$ 1,012
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 32	$ 707	$ 1,012
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	1	0	2
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 232	$ 0	$ 34
Commercial | Commercial & industrial | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Commercial & industrial | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	32	174	1,012
Commercial | Commercial & industrial | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 533	$ 0
Residential | Construction
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	2	4	7
Pre-Modification Outstanding Recorded Investment	$ 47	$ 135	$ 584
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 45	$ 135	$ 504
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	0	0	0
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 0
Residential | Construction | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	40	46
Residential | Construction | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	32	95	376
Residential | Construction | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 13	$ 0	$ 82
Residential | Residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	15	23	28
Pre-Modification Outstanding Recorded Investment	$ 1,933	$ 2,174	$ 3,262
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 1,900	$ 2,165	$ 3,167
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	1	4	1
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 101	$ 852	$ 85
Residential | Residential mortgage | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	130	0	1,992
Residential | Residential mortgage | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	1,770	2,165	1,135
Residential | Residential mortgage | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 0	$ 40
Consumer direct
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	2	2	6
Pre-Modification Outstanding Recorded Investment	$ 7	$ 16	$ 71
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 7	$ 16	$ 71
Troubled Debt Restructurings That Have Subsequently Defaulted, Number of Contracts | contract	0	0	0
Troubled Debt Restructurings That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 0
Consumer direct | Rate Reduction
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	13
Consumer direct | Structure
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	16	58
Consumer direct | Other
Financing Receivable, Modifications [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 7	$ 0	$ 0