Loans and Leases - Schedule of Activity In The Allowance For Loan Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Provision for loan losses	$ 2	$ 2	$ 6	$ 4
Institutional
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	41	30	37	28
Provision for loan losses	2	2	6	4
Ending balance	$ 43	$ 32	$ 43	$ 32