Derivative Financial Instruments And Hedging Activities Derivative (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Derivative [Line Items]
Restricted Cash - Derivative Collateral	$ 14	$ 4
Derivative Financial Instruments, Assets [Member]
Derivative [Line Items]
Notional Amount of Interest Rate Derivatives	6,734.0	775.1
Fair Value Hedge Assets	31
Foreign Exchange Contract [Member]
Derivative [Line Items]
Fair Value Hedge Assets	17
Fair Value Hedge Liabilities	(3)
EuroDollar [Member] | Other Assets [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Notional Amount of Interest Rate Derivatives	748.0
United Kingdom, Pounds | Other Assets [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Notional Amount of Interest Rate Derivatives	331.0
Norway, Krone | Other Assets [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Notional Amount of Interest Rate Derivatives	$ 190.0