Condensed Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
NET LOSS	$ (197.5)	$ (142.9)	$ 21.8	$ (433.5)
OTHER COMPREHENSIVE LOSS, NET
Net change in derivative fair value	(5.7)	(1.9)	(7.3)	(7.6)
Reclassification of net losses on derivative instruments from other comprehensive loss into net loss	4.9	0.7	8.3	(2.2)
Other	(0.2)	(0.1)	(0.3)	(0.4)
NET OTHER COMPREHENSIVE LOSS	(1.0)	(1.3)	0.7	(10.2)
COMPREHENSIVE LOSS	(198.5)	(144.2)	22.5	(443.7)
COMPREHENSIVE (INCOME) LOSS ATTRIBUTABLE TO NONCONTROLLING INTERESTS	0.4	(2.1)	(3.8)	(2.6)
COMPREHENSIVE LOSS ATTRIBUTABLE TO VALARIS	$ (198.1)	$ (146.3)	$ 18.7	$ (446.3)

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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