Restatement Restatement balance sheet effects (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Goodwill	$ 664	$ 1,006
Assets	308,721	302,609
Other liabilities	10,668	8,412
Liabilities	285,739	281,123
Retained earnings	10,847	11,001
Liabilities and Equity	308,721	302,609
Deferred Tax Assets, Net of Valuation Allowance, Current	308,721
Deferred Tax Assets, Net of Valuation Allowance	1,393
Scenario, Previously Reported [Member]
Goodwill	1,006
Assets	308,918
Other liabilities	10,477	8,443
Liabilities	285,548
Retained earnings	11,235	12,519
Liabilities and Equity	308,918
Deferred Tax Assets, Net of Valuation Allowance, Current	1,248
Restatement Adjustment [Member]
Goodwill	(342)
Assets	(197)
Other liabilities	191	(31)
Liabilities	191
Retained earnings	(388)	(1,518)
Liabilities and Equity	(197)
Deferred Tax Assets, Net of Valuation Allowance, Current	$ 145