Loans and Leases (Troubled Debt Restructurings) (Details) - Lease Financing, net $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) Contract	Sep. 30, 2015 USD ($) Contract	Sep. 30, 2016 USD ($) Contract	Sep. 30, 2015 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	19	26	74	106
Recorded Investment	$ 7.8	$ 7.6	$ 29.7	$ 24.7
Unpaid Principal Balance	$ 8.1	$ 9.4	$ 35.4	$ 30.5
Commercial
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	2	0	12	3
Recorded Investment	$ 1.5	$ 0.0	$ 12.8	$ 0.9
Unpaid Principal Balance	$ 1.5	$ 0.0	$ 17.2	$ 0.9
Commercial | Commercial and Institutional
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	1	0	5	2
Recorded Investment	$ 0.1	$ 0.0	$ 4.1	$ 0.1
Unpaid Principal Balance	$ 0.1	$ 0.0	$ 6.2	$ 0.1
Commercial | Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	1	0	7	1
Recorded Investment	$ 1.4	$ 0.0	$ 8.7	$ 0.8
Unpaid Principal Balance	$ 1.4	$ 0.0	$ 11.0	$ 0.8
Personal
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	17	26	62	103
Recorded Investment	$ 6.3	$ 7.6	$ 16.9	$ 23.8
Unpaid Principal Balance	$ 6.6	$ 9.4	$ 18.2	$ 29.6
Personal | Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	16	26	60	102
Recorded Investment	$ 6.2	$ 7.6	$ 14.8	$ 23.2
Unpaid Principal Balance	$ 6.5	$ 9.4	$ 16.1	$ 29.0
Personal | Private Client
Financing Receivable, Modifications [Line Items]
Number of Loans and Leases | Contract	1	0	2	1
Recorded Investment	$ 0.1	$ 0.0	$ 2.1	$ 0.6
Unpaid Principal Balance	$ 0.1	$ 0.0	$ 2.1	$ 0.6