Stockholders' Equity, Restricted Stock And Stock Options (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended			6 Months Ended		0 Months Ended			0 Months Ended									3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended
	Jun. 30, 2011 years	Jun. 30, 2010	Dec. 31, 2010	Jun. 30, 2011 Minimum [Member] years	Jun. 30, 2011 Maximum [Member] years	Jun. 18, 2010 5.75% Cumulative Convertible, Preferred Stock [Member]	May 17, 2010 5.75% Cumulative Convertible, Preferred Stock [Member]	Jun. 30, 2010 5.75% Cumulative Convertible, Preferred Stock [Member]	May 17, 2010 5.75% Cumulative Convertible, Preferred Stock (Series A) [Member]	Jun. 30, 2010 5.75% Cumulative Convertible, Preferred Stock (Series A) [Member]	Jun. 30, 2011 4.50% Cumulative Convertible Preferred Stock [Member]	Jun. 30, 2010 4.50% Cumulative Convertible Preferred Stock [Member]	Jun. 30, 2011 5.00% Cumulative Convertible Preferred Stock (series 2005B) [Member]	Jun. 30, 2010 5.00% Cumulative Convertible Preferred Stock (series 2005B) [Member]	Jun. 30, 2010 5.00% Cumulative Convertible, Preferred Stock (Series 2005) [Member]	May 03, 2010 5.00% Cumulative Convertible, Preferred Stock (Series 2005) [Member]	Jun. 30, 2011 Cumulative Convertible 5.75% Non-Voting Preferred Stock [Member]	Mar. 31, 2011 Unvested Restricted Stocks [Member]	Jun. 30, 2011 Unvested Restricted Stocks [Member]	Jun. 30, 2010 Unvested Restricted Stocks [Member]	Jun. 30, 2011 Unvested Stock Options [Member]	Jun. 30, 2011 Unvested Stock Options [Member]	Jun. 30, 2010 Unvested Stock Options [Member]
2.25% Contingent Convertible Senior Notes due 2038		$ 11
Maturity date		2038
Interest rate		2.25%				5.75%	5.75%		5.75%		4.50%		5.00%			5.00%	5.75%
Aggregate number of shares of common stock available for awards		298,500
Common stock issued, value		9
Gain (loss) on conversion exchange of preferred stock to for common stock		(2)
Preferred stock, shares issued	7,254,515		7,254,515			900,000	600,000	1,500,000	1,100,000	1,100,000
Preferred stock, par value	$ 0.01		$ 0.01				$ 0.01		$ 0.01
Liquidation preference per share							$ 1,000		$ 1,000
Preferred stock, shares outstanding	7,254,515		7,254,515													5,000
Proceeds from preferred stock		2,562				877	594		1,091
Convertible preferred stock, shares																20,774
Cost expected to be recognized over a weighted average period (in years)																			2
Aggregate intrinsic value of restricted stock vested	86
Unrecognized compensation cost																			350
Recognized reduction in tax benefits																		$ 1	$ 1	$ 1	$ 2	$ 3	$ 1
Employee vesting period used for value amortization, years				4	5
Non-employee directors vesting period used for value amortization, years	3