Debt (Schedule Of Long-term Debt Instruments) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Total long-term debt	$ 4,902.1	$ 240.1
Less current maturities	(222.5)	(17.2)
Commercial paper	175.0
Total debt	5,124.6	257.3
4.70% Senior Notes Due 2021 [Member]
Total long-term debt	1,471.6
Debt instrument interest rate stated percentage	4.70%
Debt instrument maturity period	2021
6.875% Senior Notes due 2020 [Member]
Total long-term debt	1,059.4
Debt instrument interest rate stated percentage	6.875%
Debt instrument maturity period	2020
3.25% Senior Notes due 2016 [Member]
Total long-term debt	993.2
Debt instrument interest rate stated percentage	3.25%
Debt instrument maturity period	2016
8.50% Senior Notes Due 2019 [Member]
Total long-term debt	635.4
Debt instrument interest rate stated percentage	8.50%
Debt instrument maturity period	2019
7.875% Senior Notes Due 2040 [Member]
Total long-term debt	385.3
Debt instrument interest rate stated percentage	7.875%
Debt instrument maturity period	2040
7.20% Debentures Due 2027 [Member]
Total long-term debt	149.0	148.9
Debt instrument interest rate stated percentage	7.20%
Debt instrument maturity period	2027
4.33% MARAD Bonds Due 2016 [Member]
Total long-term debt	155.9
Debt instrument interest rate stated percentage	4.33%
Debt instrument maturity period	2016
6.36% MARAD Bonds due 2015 [Member]
Total long-term debt	57.0	63.4
Debt instrument interest rate stated percentage	6.36%
Debt instrument maturity period	2015
4.65% MARAD Bonds due 2020 [Member]
Total long-term debt	$ 42.8	$ 45.0
Debt instrument interest rate stated percentage	4.65%
Debt instrument maturity period	2020

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

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Interest rate stated in the contractual debt agreement.

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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

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. 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, and after deducting unamortized discount or premiums, if any.

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