Financial Derivatives (Gains (Losses) on Derivatives Not Designated As Hedging Instruments under GAAP) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	$ 66	$ 45	$ 149	$ 91
Residential Mortgages [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	47	(29)	98	17
Residential Mortgages [Member] | Residential Mortgage Servicing Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	57	(172)	110	(211)
Residential Mortgages [Member] | Loan Sales Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	(10)	143	(12)	228
Commercial Mortgage Banking [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	22	1	42	6
Commercial Mortgage Banking [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	23	1	43	7
Commercial Mortgage Banking [Member] | Credit Default Swap [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	(1)		(1)	(1)
Customer Contracts [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	32	85	58	139
Customer Contracts [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	11	67	10	86
Customer Contracts [Member] | Credit Default Swap [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	(1)	(2)		(3)
Customer Contracts [Member] | Equity Contract [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net				(3)
Customer Contracts [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	22	20	48	59
Other Risk Management Activity [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	(35)	(12)	(49)	(71)
Other Risk Management Activity [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	(11)	4	(15)	4
Other Risk Management Activity [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	(5)	2	(7)	2
Other Risk Management Activity [Member] | Other Contract [Member]
Derivative [Line Items]
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net	$ (19)	$ (18)	$ (27)	$ (77)