Debt and Credit Facilities (Narrative) (Details)								12 Months Ended			1 Months Ended		1 Months Ended
	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Jun. 30, 2008 GBP (£)	Dec. 31, 2001	Apr. 30, 2009 Nine point five percent senior notes [Member] USD ($)	Dec. 31, 2011 Other Loans And Notes [Member]	Dec. 31, 2010 Other Loans And Notes [Member]	Dec. 31, 2011 Debentures With Put Feature [Member] USD ($)	Dec. 31, 2010 Debentures With Put Feature [Member] USD ($)	Apr. 30, 2009 Exchangeable Senior Notes [Member] USD ($)	May 31, 2015 Four Year Revolving Credit Facility Member [Member]	Dec. 31, 2011 Four Year Revolving Credit Facility Member [Member] USD ($)	May 31, 2013 Three Year Revolving Credit Facility [Member]	Jun. 30, 2011 Three Year Revolving Credit Facility [Member]	Dec. 31, 2011 Three Year Revolving Credit Facility [Member] USD ($)	Dec. 31, 2011 Non-U.S. [Member] USD ($)	Sep. 30, 2008 Senior Notes Due In Two Thousand Thirteen And Eighteen [Member] USD ($)
Short-term Debt, Weighted Average Interest Rate	5.40%	5.50%
Fair value of the Company's debt	$ 4,359,200,000	$ 4,131,800,000
Commercial Paper Program Maximum Aggregate Amount Available To Be Issued	2,000,000,000
Long-term debenture with fixed interest rate								343,600,000	343,600,000
Debt instrument, maturity date range, start								2027
Debt instrument, maturity date range, end								2028
Debt Instrument, Face Amount			60,000,000		655,000,000					345,000,000							1,400,000,000
Debt Instrument, Interest Rate			8.25%	11.00%	9.50%					4.50%
Portion of convertible debt allocated to debt										305,000,000
Portion of convertible debt allocated to equity, gross										40,000,000
Portion of convertible debt allocated to equity, net of allocated fees										39,000,000
Line Of Credit Facilities Amounts Expired															1,000,000,000
Line of Credit Facility, Maximum Borrowing Capacity	2,000,000,000											1,000,000,000			1,000,000,000
Line of credit facility, expiration date											May 2015		May 2013	June 2011
Other Available Non-US Lines of Credit, Borrowing Capacity																617,200,000
Other Available Non-US Lines of Credit, Remaining Borrowing Capacity																447,900,000
Commercial Paper Program, amounts outstanding	$ 0	$ 0
Other loans and notes, maturing in various amounts to 2019, end of year average interest rates						7.22%	5.55%