XML 52 R40.htm IDEA: XBRL DOCUMENT v3.21.1

Revenue from Contracts with Customers (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Net	$ 18.9
Upfront Rig Mobilizations And Certain Contract Preparation [Member]
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Net	11.2		$ 13.8
Capitalized Contract Cost, Amortization	5.8	$ 11.5
Deferred Certification Costs
Capitalized Contract Cost [Line Items]
Capitalized Contract Cost, Net	7.7		$ 8.4
Capitalized Contract Cost, Amortization	$ 2.6	$ 3.1
Minimum [Member]
Capitalized Contract Cost [Line Items]
Remaining duration of drilling contracts	1 month
Maximum [Member]
Capitalized Contract Cost [Line Items]
Remaining duration of drilling contracts	2 years

X

- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

+ Details

Name:	us-gaap_CapitalizedContractCostAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_CapitalizedContractCostLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

+ Details

Name:	us-gaap_CapitalizedContractCostNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Drilling Contracts, Term

+ References

No definition available.

+ Details

Name:	val_DrillingContractsTerm
Namespace Prefix:	val_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_CapitalizedContractCostAxis=val_UpfrontRigMobilizationsAndCertainContractPreparationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedContractCostAxis=val_DeferredCertificationCostsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: