Guarantee Of Registered Securities (Condensed Consolidating Statements of Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
NET LOSS	$ (3,007.7)	$ (188.0)
OTHER COMPREHENSIVE INCOME (LOSS), NET:
Net change in derivative fair value	(12.9)	0.0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income into net income	(0.1)	1.6
Other	(0.4)	(0.1)
NET OTHER COMPREHENSIVE INCOME (LOSS)	(13.4)	1.5
COMPREHENSIVE LOSS	(3,021.1)	(186.5)
COMPREHENSIVE (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	1.4	(2.4)
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS	(3,019.7)	(188.9)
Valaris plc
NET LOSS	(3,006.3)	(190.4)
OTHER COMPREHENSIVE INCOME (LOSS), NET:
Net change in derivative fair value	0.0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income into net income	0.0	0.0
Other	0.0	0.0
NET OTHER COMPREHENSIVE INCOME (LOSS)	0.0	0.0
COMPREHENSIVE LOSS	(3,006.3)	(190.4)
COMPREHENSIVE (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	0.0	0.0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS	(3,006.3)	(190.4)
ENSCO International Incorporated
NET LOSS	(85.0)	0.1
OTHER COMPREHENSIVE INCOME (LOSS), NET:
Net change in derivative fair value	(12.9)
Reclassification of net (gains) losses on derivative instruments from other comprehensive income into net income	(0.1)	1.6
Other	0.0	0.0
NET OTHER COMPREHENSIVE INCOME (LOSS)	(13.0)	1.6
COMPREHENSIVE LOSS	(98.0)	1.7
COMPREHENSIVE (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	0.0	0.0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS	(98.0)	1.7
Pride International LLC
NET LOSS	(13.9)	5.6
OTHER COMPREHENSIVE INCOME (LOSS), NET:
Net change in derivative fair value	0.0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income into net income	0.0	0.0
Other	0.0	0.0
NET OTHER COMPREHENSIVE INCOME (LOSS)	0.0	0.0
COMPREHENSIVE LOSS	(13.9)	5.6
COMPREHENSIVE (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	0.0	0.0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS	(13.9)	5.6
Other Non-Guarantor Subsidiaries of Valaris
NET LOSS	(3,313.8)	(108.3)
OTHER COMPREHENSIVE INCOME (LOSS), NET:
Net change in derivative fair value	0.0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income into net income	0.0	0.0
Other	(0.4)	(0.1)
NET OTHER COMPREHENSIVE INCOME (LOSS)	(0.4)	(0.1)
COMPREHENSIVE LOSS	(3,314.2)	(108.4)
COMPREHENSIVE (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	1.4	(2.4)
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS	(3,312.8)	(110.8)
Consolidating Adjustments
NET LOSS	3,411.3	105.0
OTHER COMPREHENSIVE INCOME (LOSS), NET:
Net change in derivative fair value	0.0
Reclassification of net (gains) losses on derivative instruments from other comprehensive income into net income	0.0	0.0
Other	0.0	0.0
NET OTHER COMPREHENSIVE INCOME (LOSS)	0.0	0.0
COMPREHENSIVE LOSS	3,411.3	105.0
COMPREHENSIVE (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	0.0	0.0
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS	$ 3,411.3	$ 105.0

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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