Employee Stock Ownership Plan (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 1989	Dec. 29, 2010
Notes to Financial Statements [Abstract]
Long-term notes issued by ESOP				$ 410
Average interest rate on ESOP notes (in hundredths)				8.70%
Preference stock purchased from the proceeds of the notes (in shares)				6,315,149
Number of shares of common stock that each share of preference stock can be converted (in shares)				8
Redemption price (in dollars per share)				$ 65
Preference stock retired (in shares)					2,405,192
Minimum cumulative dividend rate for Convertible Preference stock (in dollars per share)				$ 2.44
Common stock converted (in shares)					19,241,536
Common Stock Outstanding And Issued To Employee Stock Ownership Plan	15,610,648	17,102,005
Advances from the Company	41
Common shares released and allocated to participant accounts (in shares)	9,635,421
Common shares available for future allocation to participant accounts (in shares)	5,975,227
Annual ESOP expense	0	0	6
Interest incurred on ESOP notes	0	0	0
Dividends paid by the Company on shares held by the ESOP	40	42	41
Company contributions to the ESOP	$ 0	$ 0	$ 6