Earnings Per Share (Narrative) (Details) (USD $) Share data in Millions, unless otherwise specified	1 Months Ended	3 Months Ended	12 Months Ended
	Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2011	Dec. 31, 2011
Earnings Per Share [Abstract]
Shares issued related to equity unit conversion (in shares)	44
Face amount of equity units		$ 1,750,000,000		$ 1,750,000,000
Adjustment for after-tax interest			$ 13,000,000
Interest rate stated percentage				4.70%
Shares assumed issued included in adjusted average shares outstanding		44	11