Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Interest bearing deposits in banks	$ 1,703	$ 2,764
Trading account assets pledged as collateral	3	14
Fair value of securities held to maturity	1,224	1,429
Other assets	3,353	3,365
Long-term debt	5,540	6,684
Other liabilities	1,763	2,019
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 1	$ 1
Common stock, share authorized	300,000,000	300,000,000
Common stock, share issued	136,330,830	136,330,830
Common stock, share outstanding	136,330,830	136,330,830
Consolidated VIEs [Member]
Interest bearing deposits in banks	8	8
Other assets	337	286
Long-term debt	8	8
Other liabilities	$ 1	$ 1