Loan and Lease Financings (Details 6) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) modification default	Dec. 31, 2015 USD ($) modification default	Dec. 31, 2014 USD ($) modification default
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	2	2	9
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 876	$ 218	$ 8,723
Financing Receivable, Modifications, Recorded Investment	$ 2,002	$ 9,363
Troubled debt restructured loans and leases which had payment defaults within twelve months following modification
Default threshold	90 days
Interest Rate Below Market Reduction
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts	1	0	3
Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	2	4
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 218	$ 610
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| default	0	0	0
Financing Receivable, Modifications, Recorded Investment	$ 360	$ 7,437
Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	2	0	5
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 876	$ 0	$ 8,113
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| default	0	0
Financing Receivable, Modifications, Recorded Investment	$ 1,642	$ 1,926
Commercial and agricultural \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	2	2
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 218	$ 273
Commercial and agricultural \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	4
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 7,315
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| default			1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment			$ 260
Auto and light truck \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Auto and light truck \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Medium and heavy duty truck \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Medium and heavy duty truck \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Aircraft \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	2
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 337
Aircraft \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Construction equipment \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Construction equipment \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	1	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 562	$ 0	$ 0
Commercial real estate \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Commercial real estate \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	1
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 798
Residential real estate and home equity \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Residential real estate and home equity \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	1	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 314	$ 0	$ 0
Consumer \| Performing
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0
Consumer \| Nonperforming
Loans and leases classified as TDR
Financing Receivable, Modifications, Number of Contracts \| modification	0	0	0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 0	$ 0

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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