Loans and Leases (Troubled Debt Restructurings) (Details) - Lease Financing, net $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) Contract	Jun. 30, 2018 USD ($) Contract	Jun. 30, 2019 USD ($) Contract	Jun. 30, 2018 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | Contract	15	13	29	29
Recorded Investment	$ 7.7	$ 11.3	$ 25.1	$ 19.2
Unpaid Principal Balance	$ 7.8	$ 12.3	$ 26.5	$ 21.6
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | Contract	2	1	3	2
Recorded Investment	$ 0.0	$ 1.3	$ 7.6	$ 1.6
Unpaid Principal Balance	$ 0.0	$ 1.3	$ 8.8	$ 1.8
Commercial | Commercial and Institutional
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | Contract	0	0	1	1
Recorded Investment	$ 0.0	$ 0.0	$ 7.6	$ 0.3
Unpaid Principal Balance	$ 0.0	$ 0.0	$ 8.8	$ 0.5
Commercial | Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | Contract	2	1	2	1
Recorded Investment	$ 0.0	$ 1.3	$ 0.0	$ 1.3
Unpaid Principal Balance	$ 0.0	$ 1.3	$ 0.0	$ 1.3
Personal
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | Contract	13	12	26	27
Recorded Investment	$ 7.7	$ 10.0	$ 17.5	$ 17.6
Unpaid Principal Balance	$ 7.8	$ 11.0	$ 17.7	$ 19.8
Personal | Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | Contract	13	12	26	26
Recorded Investment	$ 7.7	$ 10.0	$ 17.5	$ 17.6
Unpaid Principal Balance	$ 7.8	$ 11.0	$ 17.7	$ 19.7
Personal | Private Client
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | Contract	0	0	0	1
Recorded Investment	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Unpaid Principal Balance	$ 0.0	$ 0.0	$ 0.0	$ 0.1