v2.3.0.15

Fair Value Measurements (Schedule Of Carrying Values And Estimated Fair Values Of Debt Instruments) (Details) (USD $) In Millions, unless otherwise specified | Sep. 30, 2011 | Dec. 31, 2010
--- | --- | ---
4.70% Senior Notes [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | $ 1,471.6 |
Estimated Fair Value | 1,490.3 |
Debt instrument, interest rate, stated percentage | 4.70% |
3.25% Senior Notes [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 993.2 |
Estimated Fair Value | 1,021.5 |
Debt instrument, interest rate, stated percentage | 3.25% |
6.875% Senior Notes due 2020 [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 1,059.4 |
Estimated Fair Value | 1,045.4 |
Debt instrument, interest rate, stated percentage | 6.875% |
8.50% Senior Notes [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 635.4 |
Estimated Fair Value | 612.6 |
Debt instrument, interest rate, stated percentage | 8.50% |
7.875% Senior Notes [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 385.3 |
Estimated Fair Value | 372.4 |
Debt instrument, interest rate, stated percentage | 7.875% |
7.20% Debentures [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 149.0 | 148.9
Estimated Fair Value | 169.6 | 165.0
Debt instrument, interest rate, stated percentage | 7.20% |
4.33% MARAD Bonds, Including Current Maturities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 155.9 |
Estimated Fair Value | 156.7 |
Debt instrument, interest rate, stated percentage | 4.33% |
6.36% MARAD Bonds, Including Current Maturities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 57.0 | 63.4
Estimated Fair Value | 63.8 | 71.9
Debt instrument, interest rate, stated percentage | 6.36% |
4.65% MARAD Bonds, Including Current Maturities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Carrying Value | 42.8 | 45.0
Estimated Fair Value | $ 49.1 | $ 50.6
Debt instrument, interest rate, stated percentage | 4.65% |

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- Definition Debt Instrument Carrying Value + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13476-108611 + Details
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- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + Details
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