Loans and Leases (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($) Contract	Jun. 30, 2017 USD ($) Contract	Jun. 30, 2018 USD ($) Contract	Jun. 30, 2017 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Unpaid Principal Balance			$ 0.1	$ 0.0
Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	13	17	29	38
Recorded Investment	$ 11.3	$ 8.1	$ 19.2	$ 13.4
Unpaid Principal Balance	$ 12.3	$ 8.4	$ 21.6	$ 13.8
Commercial \| Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	0	2	1
Recorded Investment	$ 1.3	$ 0.0	$ 1.6	$ 1.4
Unpaid Principal Balance	$ 1.3	$ 0.0	$ 1.8	$ 1.3
Commercial \| Lease Financing, net \| Commercial and Institutional
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	0	0	1	0
Recorded Investment	$ 0.0	$ 0.0	$ 0.3	$ 0.0
Unpaid Principal Balance	$ 0.0	$ 0.0	$ 0.5	$ 0.0
Commercial \| Lease Financing, net \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	0	1	1
Recorded Investment	$ 1.3	$ 0.0	$ 1.3	$ 1.4
Unpaid Principal Balance	$ 1.3	$ 0.0	$ 1.3	$ 1.3
Personal \| Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	12	17	27	37
Recorded Investment	$ 10.0	$ 8.1	$ 17.6	$ 12.0
Unpaid Principal Balance	$ 11.0	$ 8.4	$ 19.8	$ 12.5
Personal \| Lease Financing, net \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	12	17	26	36
Recorded Investment	$ 10.0	$ 8.1	$ 17.6	$ 12.0
Unpaid Principal Balance	$ 11.0	$ 8.4	$ 19.7	$ 12.4
Personal \| Lease Financing, net \| Private Client
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	0	0	1	1
Recorded Investment	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Unpaid Principal Balance	$ 0.0	$ 0.0	$ 0.1	$ 0.1

Financing Receivable, Modifications, Recorded Investment, Modified During Period

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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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