Loans and Leases (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) Contract	Mar. 31, 2017 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Unpaid Principal Balance	$ 0.4
Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	16	21
Recorded Investment	$ 7.8	$ 5.3
Unpaid Principal Balance	$ 9.3	$ 5.4
Commercial \| Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	1
Recorded Investment	$ 0.3	$ 1.4
Unpaid Principal Balance	$ 0.5	$ 1.4
Commercial \| Lease Financing, net \| Commercial and Institutional
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	0
Recorded Investment	$ 0.3	$ 0.0
Unpaid Principal Balance	$ 0.5	$ 0.0
Commercial \| Lease Financing, net \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	0	1
Recorded Investment	$ 0.0	$ 1.4
Unpaid Principal Balance	$ 0.0	$ 1.4
Personal \| Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	15	20
Recorded Investment	$ 7.5	$ 3.9
Unpaid Principal Balance	$ 8.8	$ 4.0
Personal \| Lease Financing, net \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	14	19
Recorded Investment	$ 7.5	$ 3.9
Unpaid Principal Balance	$ 8.7	$ 3.9
Personal \| Lease Financing, net \| Private Client
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	1
Recorded Investment	$ 0.0	$ 0.0
Unpaid Principal Balance	$ 0.1	$ 0.1

Financing Receivable, Modifications, Recorded Investment, Modified During Period

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- Definition

Financing Receivable, Modifications, Unpaid Principal Balance

+ References

No definition available.

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- Definition

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+ References

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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