Shareowners' Equity (Parenthetical) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended			3 Months Ended
	Jun. 30, 2012	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Jun. 30, 2012 First Preferred Shares Issuance [Member]	Sep. 30, 2012 Second Preferred Shares Issuance [Member]
Noncontrolling Interest [Line Items]
Preferred Stock, Shares Issued		40,000		0	22,500	17,500
Preferred Stock, Par or Stated Value Per Share		$ 0.01		$ 0.01	$ 0.01	$ 0.01
Proceeds From Issuance Of Preferred Stock		$ 3,960	$ 0		$ 2,227	$ 1,733
Initial Fixed Interest Rate Of Preferred Stock					7.125%	6.25%
Percentage Points Over Three Month LIBOR					5.296%	4.704%
Dividend Amount Paid To Parent	471	946
Special Dividend Paid To Parent	$ 1,975	$ 4,500