Cover Page - shares	9 Months Ended
Sep. 30, 2019	Oct. 23, 2019
Entity Information [Line Items]
Entity Incorporation, State or Country Code	X0
Document Transition Report	false
Document Quarterly Report	true
Document Type	10-Q
Entity File Number	1-8097
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Entity Registrant Name	Valaris plc
Entity Central Index Key	0000314808
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Shares, Shares Outstanding		197,877,182
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Address, Address Line One	6 Chesterfield Gardens
Entity Address, City or Town	London,
City Area Code	44 (0) 20
Local Phone Number	7659 4660
Entity Address, State or Province	GB
Entity Tax Identification Number	98-0635229
Entity Address, Postal Zip Code	W1J 5BQ
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0000314808
Class A ordinary shares, U.S. $0.40 par value
Entity Information [Line Items]
Title of 12(b) Security	Class A ordinary shares, U.S. $0.40 par value
Trading Symbol	VAL
Security Exchange Name	NYSE
4.70% Senior notes due 2021
Entity Information [Line Items]
Title of 12(b) Security	4.70% Senior Notes due 2021
Trading Symbol	VAL21
Security Exchange Name	NYSE
4.50% Senior Notes due 2024
Entity Information [Line Items]
Title of 12(b) Security	4.50% Senior Notes due 2024
Trading Symbol	VAL24
Security Exchange Name	NYSE
8.00% Senior Notes due 2024
Entity Information [Line Items]
Title of 12(b) Security	8.00% Senior Notes due 2024
Trading Symbol	VAL24A
Security Exchange Name	NYSE
5.20% Senior notes due 2025
Entity Information [Line Items]
Title of 12(b) Security	5.20% Senior Notes due 2025
Trading Symbol	VAL25A
Security Exchange Name	NYSE
7.75% Senior notes due 2026
Entity Information [Line Items]
Title of 12(b) Security	7.75% Senior Notes due 2026
Trading Symbol	VAL26
Security Exchange Name	NYSE
5.75% Senior notes due 2044
Entity Information [Line Items]
Title of 12(b) Security	5.75% Senior Notes due 2044
Trading Symbol	VAL44
Security Exchange Name	NYSE

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