Fair Values of Assets and Liabilities (Details Textual) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Fair Values of Assets and Liabilities (Textual) [Abstract]
Fair value measurement transfers from one level to another			$ 0	$ 0
Mortgage loans held for sale measured at fair value gain losses	98,000,000	(26,000,000)	38,000,000	100,000,000
Mortgage loans held for sale	5,200,000,000		5,200,000,000
Fair value of mortgage loans held for sale exceeded the unpaid principal	242,000,000		242,000,000
Carrying value of unfunded commitments and standby letters of credit	358,000,000		358,000,000		353,000,000
Carrying value of other guarantees	372,000,000		372,000,000		330,000,000
Net gains and losses on net derivative assets and liabilities included in other non interest income	445,000,000	252,000,000	672,000,000	865,000,000
Net gains and losses on net derivative assets and liabilities included in mortgage banking revenue	391,000,000	430,000,000	580,000,000	876,000,000
Net Change on other assets and liabilities in unrealized gains (Losses) included in other non interest income	317,000,000	504,000,000	303,000,000	842,000,000
Net Change on other assets and liabilities in unrealized gains (Losses) included in mortgage banking revenue	(240,000,000)	(385,000,000)	(395,000,000)	(682,000,000)
Net gains and losses on net derivative assets and liabilities included in securities gains (losses)	(9,000,000)	(18,000,000)	(24,000,000)	(85,000,000)
Net gains and losses on net derivative assets and liabilities included in interest income	$ 13,000,000	$ 18,000,000	$ 44,000,000	$ 45,000,000