Loan and Lease Financings (Details 3) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	$ 4,007,823	$ 3,969,357
90 Days or More Past Due and Accruing	729	122
Total Accruing Loans	4,018,993	3,981,974
Nonaccrual	12,982	12,718
Total loans and leases	4,031,975	3,994,692
30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	8,444	11,649
60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	1,997	846
Commercial and agricultural
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	744,858	740,335
Total Accruing Loans	745,030	740,466
Nonaccrual	3,994	4,283
Total loans and leases	749,024	744,749
Commercial and agricultural \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	131	52
Commercial and agricultural \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	41	79
Auto and light truck
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	428,216	424,997
Total Accruing Loans	428,403	425,190
Nonaccrual	52	46
Total loans and leases	428,455	425,236
Auto and light truck \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	173	170
Auto and light truck \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	14	23
Medium and heavy duty truck
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	272,917	278,254
Total Accruing Loans	272,917	278,254
Nonaccrual	0	0
Total loans and leases	272,917	278,254
Medium and heavy duty truck \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	0
Medium and heavy duty truck \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	0
Aircraft financing
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	772,547	764,074
Total Accruing Loans	779,826	773,624
Nonaccrual	4,018	4,388
Total loans and leases	783,844	778,012
Aircraft financing \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	5,894	9,442
Aircraft financing \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	1,385	108
Construction equipment financing
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	466,239	454,993
Total Accruing Loans	467,246	455,026
Nonaccrual	536	539
Total loans and leases	467,782	455,565
Construction equipment financing \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	655	33
Construction equipment financing \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	352	0
Commercial real estate
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	714,408	698,514
Total Accruing Loans	714,799	698,876
Nonaccrual	1,811	1,392
Total loans and leases	716,610	700,268
Commercial real estate \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	391	362
Commercial real estate \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	0
Residential real estate and home equity
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	463,015	460,771
90 Days or More Past Due and Accruing	702	71
Total Accruing Loans	464,607	462,307
Nonaccrual	1,843	1,822
Total loans and leases	466,450	464,129
Residential real estate and home equity \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	758	1,038
Residential real estate and home equity \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	132	427
Consumer
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	145,623	147,419
90 Days or More Past Due and Accruing	27	51
Total Accruing Loans	146,165	148,231
Nonaccrual	728	248
Total loans and leases	146,893	148,479
Consumer \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	442	552
Consumer \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	$ 73	$ 209

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

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- Definition

Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953401-111524

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+ References

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

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+ References

No definition available.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524

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