Loan and Lease Financings (Details 3) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	$ 4,128,724	$ 3,969,357
90 Days or More Past Due and Accruing	276	122
Total Accruing Loans	4,140,184	3,981,974
Nonaccrual	12,579	12,718
Total loans and leases	4,152,763	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	10,718	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	466	846
Commercial and agricultural
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	755,391	740,335
Total Accruing Loans	755,582	740,466
Nonaccrual	3,593	4,283
Total loans and leases	759,175	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	175	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	16	79
Auto and light truck
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	457,190	424,997
Total Accruing Loans	457,539	425,190
Nonaccrual	47	46
Total loans and leases	457,586	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	336	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	13	23
Medium and heavy duty truck
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	273,674	278,254
Total Accruing Loans	273,674	278,254
Nonaccrual	0	0
Total loans and leases	273,674	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
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	811,062	764,074
Total Accruing Loans	818,562	773,624
Nonaccrual	4,280	4,388
Total loans and leases	822,842	778,012
Aircraft \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	7,500	9,442
Aircraft \| 60 to 89 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	108
Construction equipment
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	482,657	454,993
Total Accruing Loans	483,685	455,026
Nonaccrual	669	539
Total loans and leases	484,354	455,565
Construction equipment \| 30 to 59 Days Past Due
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	1,028	33
Construction equipment \| 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
Commercial real estate
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	713,651	698,514
Total Accruing Loans	714,205	698,876
Nonaccrual	1,727	1,392
Total loans and leases	715,932	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	554	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	479,970	460,771
90 Days or More Past Due and Accruing	234	71
Total Accruing Loans	481,362	462,307
Nonaccrual	1,617	1,822
Total loans and leases	482,979	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	769	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	389	427
Consumer
Recorded investment of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	155,129	147,419
90 Days or More Past Due and Accruing	42	51
Total Accruing Loans	155,575	148,231
Nonaccrual	646	248
Total loans and leases	156,221	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	356	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	$ 48	$ 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
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: 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=66008989&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=66008989&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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: 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=66008989&loc=SL6953401-111524

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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=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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