v2.3.0.15

Earnings Per Share (Reconciliation Of Net Income Attributable To Ensco Shares) (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Earnings Per Share [Abstract]
Net income attributable to Ensco	$ 204.5	$ 130.5	$ 371.0	$ 446.6
Net income allocated to non-vested share awards	(2.3)	(1.8)	(4.3)	(5.7)
Net income attributable to Ensco shares	$ 202.2	$ 128.7	$ 366.7	$ 440.9

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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