Long-Term Obligations (Schedule Of Carrying Amount Of Convertible Senior Notes) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Long-term Debt, net	$ 8,077,246	$ 7,605,734
Total Debt, Including Long-Term and Short-Term Portions	9,427,246	7,605,734
Long-term Debt, Current Maturities	1,350,000	0
Long-term Debt, Excluding Current Maturities	8,077,246	7,605,734
May 2013 Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	614,791	607,036
Debt Instrument, Interest Rate, Stated Percentage	0.625%
May 2014 Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	1,188,594	1,181,525
Debt Instrument, Interest Rate, Stated Percentage	1.00%
May 2016 Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	1,138,538	1,132,293
Debt Instrument, Interest Rate, Stated Percentage	1.625%
April 2021 Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	992,280	992,066
Debt Instrument, Interest Rate, Stated Percentage	4.50%
December 2014 Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	749,157	749,078
Debt Instrument, Interest Rate, Stated Percentage	2.40%
December 2016 Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	698,921	698,864
Debt Instrument, Interest Rate, Stated Percentage	3.05%
December 2021 Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	1,247,212	1,247,138
Debt Instrument, Interest Rate, Stated Percentage	4.40%
December 2041 Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, net	997,753	997,734
Debt Instrument, Interest Rate, Stated Percentage	5.65%
Term Loan Facility due January 2015 [Member]
Debt Instrument [Line Items]
Carrying amount of term loan facility	650,000	0
Credit Facility Due January 2013 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	400,000	0
Credit Facility Due January 2017 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	$ 750,000	$ 0

Carrying amount of term loan facility

No definition available.

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- Definition

Total Debt, Including Long-Term and Short-Term Portions

+ References

No definition available.

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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- Definition

Amount borrowed under the credit facility as of the balance sheet date.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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- Definition

Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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-Publisher SEC

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