Loans and Leases (Troubled Debt Restructurings) (Details) - Lease Financing, net $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) Contract	Mar. 31, 2016 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	21	31
Recorded Investment	$ 5.3	$ 14.9
Unpaid Principal Balance	$ 5.4	$ 19.9
Commercial
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	7
Recorded Investment	$ 1.4	$ 9.4
Unpaid Principal Balance	$ 1.4	$ 13.7
Commercial \| Commercial and Institutional
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	0	2
Recorded Investment	$ 0.0	$ 4.0
Unpaid Principal Balance	$ 0.0	$ 6.0
Commercial \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	5
Recorded Investment	$ 1.4	$ 5.4
Unpaid Principal Balance	$ 1.4	$ 7.7
Personal
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	20	24
Recorded Investment	$ 3.9	$ 5.5
Unpaid Principal Balance	$ 4.0	$ 6.2
Personal \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	19	24
Recorded Investment	$ 3.9	$ 5.5
Unpaid Principal Balance	$ 3.9	$ 6.2
Personal \| Private Client
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	0
Recorded Investment	$ 0.0	$ 0.0
Unpaid Principal Balance	$ 0.1	$ 0.0

Financing Receivable, Modifications, Recorded Investment, Modified During Period

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- Definition

Financing Receivable, Modifications, Unpaid Principal Balance

+ References

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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=66008989&loc=SL6953676-111524

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