v2.4.0.6
Long-Term Obligations (Narrative) (Details) (USD $)
Share data in Millions, except Per Share data, unless otherwise specified
 1 Months Ended 12 Months Ended 1 Months Ended 1 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended 1 Months Ended 12 Months Ended
May 31, 2011
Aug. 31, 2010
May 31, 2010
Apr. 30, 2009
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Dec. 31, 2011
Warrants Expiring In 2011 [Member]
Dec. 31, 2011
Warrants Expiring In 2013 [Member]
Dec. 31, 2011
Warrants Expiring In 2014 [Member]
Dec. 31, 2011
Warrants Expiring In 2016 [Member]
Apr. 30, 2006
Warrants Expiring In 2011 And 2013 [Member]
Jul. 31, 2010
Warrants Expiring In 2014 And 2016 [Member]
Apr. 30, 2006
May 2011 And May 2013 Notes Conversion Requirements [Member]
Apr. 30, 2006
May 2011 And May 2013 Convertible Notes Hedges And Warrants [Member]
Jul. 31, 2010
May 2014 And May 2016 Convertible Notes Hedges And Warrants [Member]
Apr. 30, 2006
May 2014 And May 2016 Convertible Notes Hedges And Warrants [Member]
Dec. 31, 2011
May 2016 Convertible Senior Notes [Member]
Apr. 30, 2006
May 2011 Convertible Senior Notes [Member]
Dec. 31, 2011
May 2011 Convertible Senior Notes [Member]
Apr. 30, 2006
May 2013 Convertible Senior Notes [Member]
Dec. 31, 2011
May 2013 Convertible Senior Notes [Member]
Jul. 31, 2010
May 2014 Convertible Senior Notes [Member]
Dec. 31, 2011
May 2014 Convertible Senior Notes [Member]
Jul. 31, 2010
May 2016 Convertible Senior Notes [Member]
Dec. 31, 2011
May 2016 Convertible Senior Notes [Member]
Dec. 31, 2011
December 2014 Senior Unsecured Notes [Member]
Dec. 31, 2011
December 2016 Senior Unsecured Notes [Member]
Dec. 31, 2011
December 2021 Senior Unsecured Notes [Member]
Mar. 31, 2011
December 2021 Senior Unsecured Notes [Member]
Mar. 31, 2011
April 2021 Senior Unsecured Notes [Member]
Dec. 31, 2011
December 2041 Senior Unsecured Notes [Member]
Dec. 31, 2011
Senior Unsecured Notes [Member]
Apr. 30, 2006
Total May 2011 And 2013 Convertible Senior Notes [Member]
Dec. 31, 2011
Total May 2011 And 2013 Convertible Senior Notes [Member]
Dec. 31, 2010
Total May 2011 And 2013 Convertible Senior Notes [Member]
Dec. 31, 2009
Total May 2011 And 2013 Convertible Senior Notes [Member]
Jul. 31, 2010
Total May 2014 And May 2016 Convertible Senior Notes [Member]
Dec. 31, 2011
Total May 2014 And May 2016 Convertible Senior Notes [Member]
Dec. 31, 2010
Total May 2014 And May 2016 Convertible Senior Notes [Member]
Apr. 30, 2006
Total May 2014 And May 2016 Convertible Senior Notes [Member]
Dec. 31, 2011
Maximum [Member]
Dec. 31, 2011
Minimum [Member]
Debt Instrument [Line Items]                                                                                      
Repayment of May 2011 Notes $ 650,000,000                                                                                    
Cash paid related to the conversion spread of the May 2011 Notes 36,100,000                                                                                    
Cash received from the convertible note hedges related to the May 2011 Notes 36,100,000                                                                                    
Number of trading days taking in consideration for conversion                                                                   20       20          
Number of consecutive trading day taking in consideration for conversion                                                                   30       30          
Percentage of conversion price per share                                                                   130.00%       130.00%          
Percentage of principal amount plus accrued and unpaid interest                                                             101.00%   101.00% 100.00%       100.00%          
Convertible senior notes, effective interest rate on the liability components                                       5.70%   5.80%   3.50%   4.00%                                  
Senior Notes, stated interest rate                                     0.50%   0.625%   1.00%   1.625%   2.40% 3.05% 4.40%   4.50% 5.65%                      
Initial conversion ratio                                     25.8048   26.2460   22.1845   22.0214                                    
Principal amount applied to initial conversion ratio                                     1,000   1,000   1,000   1,000                               1,000    
Payments of debt issuance costs                                                             5,800,000   20,000,000 23,800,000       37,500,000          
Debt instrument conversion price per share                                   $ 45.41 $ 38.75 $ 38.75 $ 38.10 $ 38.10 $ 45.08 $ 45.08 $ 45.41                                    
Number of business day period after any measurement period                                                                           5          
Number of consecutive trading days for each trading day                                                                           10          
Percentage of principal amount of notes less than the product of the last reported sale price                                                                           98.00%          
Payments to acquire convertible note hedges         0 362,622,000 0             379,100,000     362,600,000                                                    
Proceeds from Issuance of Warrants         0 155,425,000 0         235,500,000 155,400,000                                                            
Net cost of convertible note hedge and warrant transactions                             143,700,000 207,200,000                                                      
Effective conversion price                                     $ 50.80   $ 53.90   $ 56.76   $ 60.10                                    
Common stock covered by the Convertible Note Hedges, subject to anti-dilution adjustments                           33.8     55.3                                                    
Common stock underlying the warrants, subject to anti-dilution adjustments                       33.8 55.3                                                            
Repurchase of common stock relating to sale of notes, shares                                                                   16.7                  
Repurchase of common stock relating to sale of notes, value                                                                   544,900,000                  
Interest expense, long-term debt                                                                     46,300,000 67,900,000 64,600,000   84,900,000 34,900,000      
Principal amount of senior notes                                     650,000,000   650,000,000   1,250,000,000   1,250,000,000   750,000,000 700,000,000 1,250,000,000   1,000,000,000 1,000,000,000 3,700,000,000                    
Percentage of principal amount of the notes to be redeemed                                                         100.00%   100.00% 100.00% 100.00%                    
Additional basis points for redemptuon of notes                                                     35 35   40 20 40                      
Additional basis points for interest rate under credit agreement                                                                                   32 20
Borrowing under the credit agreement         4,000,000                                                                            
Proceeds from Lines of Credit     500,000,000 400,000,000 0 500,000,000 400,000,000                                                                        
Amount available under the credit agreement         1,250,000,000                                                                            
Warrants exercise price               50.80 53.90 56.76 60.10                                                                
Repayments of Lines of Credit   500,000,000     0 500,000,000 400,000,000                                                                        
Converted value in excess of principal for convertible debt.                                           $ 48,300,000