Loans and Leases (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) Contract	Sep. 30, 2017 USD ($) Contract	Sep. 30, 2018 USD ($) Contract	Sep. 30, 2017 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Unpaid Principal Balance			$ 0.5
Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	12	23	41	61
Recorded Investment	$ 5.1	$ 8.0	$ 24.3	$ 21.3
Unpaid Principal Balance	$ 5.7	$ 9.3	$ 27.4	$ 23.0
Commercial | Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	1	2	3	3
Recorded Investment	$ 1.5	$ 0.0	$ 3.1	$ 1.3
Unpaid Principal Balance	$ 1.5	$ 1.0	$ 3.3	$ 2.3
Commercial | Lease Financing, net | Commercial and Institutional
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	0	2	1	2
Recorded Investment	$ 0.0	$ 0.0	$ 0.3	$ 0.0
Unpaid Principal Balance	$ 0.0	$ 1.0	$ 0.5	$ 1.0
Commercial | Lease Financing, net | Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	1	0	2	1
Recorded Investment	$ 1.5	$ 0.0	$ 2.8	$ 1.3
Unpaid Principal Balance	$ 1.5	$ 0.0	$ 2.8	$ 1.3
Personal | Lease Financing, net
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	11	21	38	58
Recorded Investment	$ 3.6	$ 8.0	$ 21.2	$ 20.0
Unpaid Principal Balance	$ 4.2	$ 8.3	$ 24.1	$ 20.7
Personal | Lease Financing, net | Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	11	21	37	57
Recorded Investment	$ 3.6	$ 8.0	$ 21.2	$ 20.0
Unpaid Principal Balance	$ 4.2	$ 8.3	$ 24.0	$ 20.6
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