Stockholders' Equity, Restricted Stock, Stock Options And Noncontrolling Interests (Information Related To Stock Option Activity) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2012 Y		Dec. 31, 2011 Y
Number Of Shares Underlying Options
Outstanding at beginning of period	1,051
Exercised	(109)
Outstanding and exercisable at end of period	942
Weighted Average Exercise Price Per Share
Outstanding at beginning of period	$ 9.84
Exercised	$ 7.08
Outstanding and exercisable at end of period	$ 10.17
Weighted Average Contract Life in Years
Outstanding at beginning of period	1.24		1.41
Outstanding and exercisable at end of period	1.24		1.41
Aggregate Intrinsic Value
Outstanding at beginning of period	$ 13	[1]
Outstanding and exercisable at end of period	$ 12	[1]	$ 13	[1]

[1] The intrinsic value of a stock option is the amount by which the current market value or the market value upon exercise of the underlying stock exceeds the exercise price of the option.