Comprehensive Income (Components Of Other Comprehensive Income, Net Of Tax) (Details) (USD $) In Millions | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | |
| Comprehensive Income [Abstract] | ||||
| Net income | $ 206.1 | $ 132.1 | $ 375.2 | $ 451.6 |
| Net change in fair value of derivatives | (7.6) | 8.7 | (1.6) | 5.7 |
| Reclassification of gains and losses on derivative instruments from other comprehensive (income) loss into net income | (0.5) | 0.2 | (2.8) | (1.3) |
| Other | 5.8 | 5.8 | ||
| Net other comprehensive income (loss) | (2.3) | 8.9 | 1.4 | 4.4 |
| Comprehensive income | 203.8 | 141.0 | 376.6 | 456.0 |
| Comprehensive income attributable to noncontrolling interests | (1.6) | (1.6) | (4.2) | (5.0) |
| Comprehensive income attributable to Ensco | $ 202.2 | $ 139.4 | $ 372.4 | $ 451.0 |
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- Definition Accumulated Other Comprehensive Income, Gains And Losses On Derivative Instruments, Other
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- Definition Comprehensive Income [Abstract]
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- Definition The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to noncontrolling interests, if any. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents Other Comprehensive Income or Loss, Net of Tax, for the period. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Net of tax effect of the reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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