Net Income Per Share (Common Stock Equivalents That Were Not Included In Calculation Of Diluted Net Income Per Share) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified					12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008	Dec. 31, 2012 Employee Stock Options [Member]		Dec. 31, 2011 Employee Stock Options [Member]		Dec. 31, 2010 Employee Stock Options [Member]		Dec. 31, 2012 Warrants To Purchase Common Stock [Member]		Dec. 31, 2011 Warrants To Purchase Common Stock [Member]		Dec. 31, 2010 Warrants To Purchase Common Stock [Member]		Dec. 31, 2012 Convertible Debt Instruments [Member]		Dec. 31, 2011 Convertible Debt Instruments [Member]		Dec. 31, 2010 Convertible Debt Instruments [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents that were not included in the calculation of diluted net income per share					6.9	[1],[2]	6.3	[1],[2]	1.8	[1],[2]	15.8	[3]	15.8	[3]	15.5	[3]	15.8	[4]	15.8	[4]	15.5	[4]
Exercise price of warrants	35.88	35.88	36.60	36.60
Conversion price	$ 23.77	$ 23.77	$ 24.25

[1] For 2012 these common stock equivalents were excluded because the effect of their inclusion would reduce our net loss per share in this period and would be antidilutive. In addition, the exercise prices of these common stock equivalents exceeded the average market price of our common stock during this period.

[2] For 2011 and 2010, these common stock equivalents were excluded because their exercise prices exceeded the average market price of our common stock during this period, and the effect of their inclusion would be antidilutive.

[3] These common stock equivalents were excluded because their exercise prices ($35.88, $35.88, and $36.60 per share for the warrants in 2012, 2011, and 2010, respectively) exceeded the average market price of our common stock during these periods, and the effect of their inclusion would be antidilutive.

[4] These common stock equivalents were excluded because the conversion prices ($23.77, $23.77, and $24.25 per share in 2012, 2011, and 2010, respectively) exceeded the average market price of our common stock during these periods, and the effect of their inclusion would be antidilutive.