Notes (Details) (USD $)	6 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Notes (Textuals) [Abstract]
Unsecured notes of $5.1 billion	$ 5,096,250,000	$ 5,185,180,000
Outstanding unsecured notes	5,100,000
Public Notes, stated interest rate	6.95%
Repayment of unsecured notes	93,100,000
Weighted average interest rate 5.17%	5.17%
Interest rate range from minimum	0.69%
Interest rate range to maximum	7.57%
Term loan facility amount	$ 500,000,000
No of extension options	2
Period of extension options	1
Maturity date description	October 5,2012

Represents the number of options available to the company to extend the maturity date of the term loan.

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- Definition

Represents an extension period (in years) of the maturity date on the company's term loan.

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The stated principal amount of the term loan at time of issuance.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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Interest rate stated in the contractual debt agreement.

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- Definition

When presenting a range of interest rates, the highest stated (contractual) rate for funds borrowed under the debt agreement as of the balance sheet date.

+ References

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When presenting a range of interest rates, the lowest stated (contractual) rate for funds borrowed under the debt agreement as of the balance sheet date.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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-Publisher FASB
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Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of long-term debt outstanding by type or by instrument at that time.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

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