Loan and Lease Financings (Details 2)	12 Months Ended
Dec. 31, 2015 USD ($) method	Dec. 31, 2014 USD ($)
Receivables [Abstract]
Number of methods to assess credit risk \| method	2
Loan and Lease Financings
Recorded investment in loans and leases	$ 3,994,692,000	$ 3,688,574,000
Loan and lease financings excluding residential real estate and consumer loans
Loan and Lease Financings
Recorded investment in loans and leases	3,382,084,000	3,100,005,000
Commercial and agricultural
Loan and Lease Financings
Recorded investment in loans and leases	744,749,000	710,758,000
Auto and light truck
Loan and Lease Financings
Recorded investment in loans and leases	425,236,000	397,902,000
Medium and heavy duty truck
Loan and Lease Financings
Recorded investment in loans and leases	278,254,000	247,153,000
Aircraft financing
Loan and Lease Financings
Recorded investment in loans and leases	778,012,000	727,665,000
Construction equipment financing
Loan and Lease Financings
Recorded investment in loans and leases	455,565,000	399,940,000
Commercial real estate
Loan and Lease Financings
Recorded investment in loans and leases	700,268,000	616,587,000
Credit Quality Grades 1-6 \| Loan and lease financings excluding residential real estate and consumer loans
Loan and Lease Financings
Recorded investment in loans and leases	3,278,484,000	2,985,162,000
Credit Quality Grades 1-6 \| Commercial and agricultural
Loan and Lease Financings
Recorded investment in loans and leases	710,030,000	683,169,000
Credit Quality Grades 1-6 \| Auto and light truck
Loan and Lease Financings
Recorded investment in loans and leases	413,836,000	380,425,000
Credit Quality Grades 1-6 \| Medium and heavy duty truck
Loan and Lease Financings
Recorded investment in loans and leases	275,367,000	243,798,000
Credit Quality Grades 1-6 \| Aircraft financing
Loan and Lease Financings
Recorded investment in loans and leases	750,264,000	691,018,000
Credit Quality Grades 1-6 \| Construction equipment financing
Loan and Lease Financings
Recorded investment in loans and leases	448,683,000	393,965,000
Credit Quality Grades 1-6 \| Commercial real estate
Loan and Lease Financings
Recorded investment in loans and leases	680,304,000	592,787,000
Credit Quality Grades 7-12
Loan and Lease Financings
Threshold value of loan or lease for evaluation of the appropriateness of the impairment reserve	100,000
Credit Quality Grades 7-12 \| Loan and lease financings excluding residential real estate and consumer loans
Loan and Lease Financings
Recorded investment in loans and leases	103,600,000	114,843,000
Credit Quality Grades 7-12 \| Commercial and agricultural
Loan and Lease Financings
Recorded investment in loans and leases	34,719,000	27,589,000
Credit Quality Grades 7-12 \| Auto and light truck
Loan and Lease Financings
Recorded investment in loans and leases	11,400,000	17,477,000
Credit Quality Grades 7-12 \| Medium and heavy duty truck
Loan and Lease Financings
Recorded investment in loans and leases	2,887,000	3,355,000
Credit Quality Grades 7-12 \| Aircraft financing
Loan and Lease Financings
Recorded investment in loans and leases	27,748,000	36,647,000
Credit Quality Grades 7-12 \| Construction equipment financing
Loan and Lease Financings
Recorded investment in loans and leases	6,882,000	5,975,000
Credit Quality Grades 7-12 \| Commercial real estate
Loan and Lease Financings
Recorded investment in loans and leases	$ 19,964,000	$ 23,800,000

Represents the amount of loans and leases where the internal credit quality grade is at or below a predetermined classification which are included in comprehensive analysis.

No definition available.

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- Definition

Represents the number of methods to assess credit risk of loans and leases receivables.

+ References

No definition available.

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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

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=49124121&loc=d3e5074-111524

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