Loans and Leases (Troubled Debt Restructurings) (Details) - Lease Financing, net $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) Contract	Mar. 31, 2018 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	14	16
Recorded Investment	$ 17.4	$ 7.8
Unpaid Principal Balance	$ 18.7	$ 9.3
Commercial
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	1
Recorded Investment	$ 7.6	$ 0.3
Unpaid Principal Balance	$ 8.8	$ 0.5
Commercial \| Commercial and Institutional
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	1	1
Recorded Investment	$ 7.6	$ 0.3
Unpaid Principal Balance	$ 8.8	$ 0.5
Commercial \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	0	0
Recorded Investment	$ 0.0	$ 0.0
Unpaid Principal Balance	$ 0.0	$ 0.0
Personal
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	13	15
Recorded Investment	$ 9.8	$ 7.5
Unpaid Principal Balance	$ 9.9	$ 8.8
Personal \| Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	13	14
Recorded Investment	$ 9.8	$ 7.5
Unpaid Principal Balance	$ 9.9	$ 8.7
Personal \| Private Client
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases \| Contract	0	1
Recorded Investment	$ 0.0	$ 0.0
Unpaid Principal Balance	$ 0.0	$ 0.1

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://fasb.org/us-gaap/role/ref/legacyRef
-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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