Share Repurchase Programs (Details Textual) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended		2 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Feb. 29, 2012 Share Repurchase Program Aug 2011 [Member]	Sep. 30, 2012 Share Repurchase Program Aug 2011 [Member]	Sep. 30, 2012 Share Repurchase Program Aug 2012 [Member]	Sep. 30, 2012 Share Repurchase Program Combination One [Member]
Share Repurchase Program (Textual) [Abstract]
Amount authorized for repurchase of outstanding common stock	$ 4,300			$ 750	$ 500
Repurchase of common stock, shares	45.0		1.6	6.7		0.7
Average per share price of repurchase of common stock			$ 114.85	$ 111.87		$ 122.02
Repurchase of common stock, value	274	1,221	188
Payments for Repurchase of Common Stock	274	1,221				86
Maximum value of shares repurchased under share re-purchase program					$ 414