Indemnification Assets (Submission Of Qualifying Losses For Reimbursement From FDIC) (Details) - IndyMac Transaction - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Qualifying Losses for Reimbursement [Line Items]
Unpaid principal balance	$ 3,196.5	$ 3,832.1
Cumulative losses incurred	3,800.6	3,727.8
Cumulative claims	3,794.7	3,722.9
Cumulative reimbursement	$ 939.9	$ 893.7