Aggregate maximum possible milestone payments to be made on attaining sales targets.

No definition available.

Name:	clvs_AggregatePaymentToBeMadeOnAttainingSalesTarget
Namespace Prefix:	clvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum potential development regulatory milestone payments to be made in the future if regulatory and other milestones are met.

+ References

No definition available.

+ Details

Name:	clvs_FutureExpectedDevelopmentRegulatoryAndSalesMilestonePayments
Namespace Prefix:	clvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of annual sales target above which the majority of the sales milestone payments must be made.

+ References

No definition available.

+ Details

Name:	clvs_FutureExpectedRegulatoryAndDevelopmentPayment
Namespace Prefix:	clvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash payments incurred to license the use and development of a drug product from the licensor. The upfront payments are expensed to acquired in process research and development if it is determined that the in-licensed product does not have an alternative future use at the time the in-license agreement is executed.

+ References

No definition available.

+ Details

Name:	clvs_InLicensingArrangementCostsUpFrontPayment
Namespace Prefix:	clvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of acquired in process research and development milestones paid to Pfizer prior to FDA approval of Rucaparib.

+ References

No definition available.

+ Details

Name:	clvs_MilestonesPaidPriorToFdaApproval
Namespace Prefix:	clvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of additional undisclosed targets.

+ References

No definition available.

+ Details

Name:	clvs_NumberOfAdditionalUndisclosedTargets
Namespace Prefix:	clvs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of Investigational New Drug Applications (INDs) submitted or to be submitted for the treatment.

+ References

No definition available.

+ Details

Name:	clvs_NumberOfInvestigationalDrugApplications
Namespace Prefix:	clvs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of consideration payable on sublicense agreements.

+ References

No definition available.

+ Details

Name:	clvs_PercentageOfConsiderationPayableOnSublicenseAgreements
Namespace Prefix:	clvs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of royalty on net sales of licensed products.

+ References

No definition available.

+ Details

Name:	clvs_PercentageOfRoyaltyOnNetSalesOfLicensedProducts
Namespace Prefix:	clvs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Milestone payments due under licensing agreements.

+ References

No definition available.

+ Details

Name:	clvs_SalesMilestonePaymentsDueUnderLicensingAgreements
Namespace Prefix:	clvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Milestone payments under in-licensing agreements.

+ References

No definition available.

+ Details

Name:	clvs_SalesMilestonePaymentsUnderInLicensingAgreements
Namespace Prefix:	clvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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

- Definition

The amount of the write-off for research and development assets that were acquired in a transaction other than a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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

- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 730
-Section 25
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6472174&loc=d3e58812-109433

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

+ Details

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

- Details

Name:	clvs_LicenseAgreementsTypeAxis=clvs_LicenseAgreements3bPharmaceuticalsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	clvs_LicenseAgreementsLicensorsNameAxis=clvs_LicenseAgreementsLicensorPfizerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	clvs_LicenseAgreementsTypeAxis=clvs_LicenseAgreementsRucaparibMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

Name:	us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis=us-gaap_LicenseAgreementTermsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	clvs_LicenseAgreementsLicensorsNameAxis=clvs_AdvenchenLaboratoriesLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	clvs_LicenseAgreementsTypeAxis=clvs_LicenseAgreementsLucitanibMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

License Agreements (Details) $ in Millions		1 Months Ended							6 Months Ended	12 Months Ended	60 Months Ended
License Agreements (Details) $ in Millions	Nov. 19, 2013 USD ($)	Sep. 30, 2021 USD ($)	Apr. 30, 2021 USD ($)	Dec. 31, 2020 item	Feb. 29, 2020 item	Sep. 30, 2019 USD ($)	Jun. 30, 2011 USD ($)	Oct. 31, 2008	Jun. 30, 2022 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)
License Agreements
Number of INDs \| item				2
3B Pharmaceuticals
License Agreements
Percentage of non-royalty consideration payable on sublicense agreements									34.00%
License Agreements Licensor Pfizer \| Rucaparib \| Minimum
License Agreements
Annual sales target for sales milestone payments									$ 250.0
License Agreements Licensor Pfizer \| Rucaparib \| Maximum
License Agreements
Maximum potential future development, regulatory milestone payments									8.0
Additional maximum payments payable on attaining the sales target									$ 170.0
License Agreement Terms \| 3B Pharmaceuticals
License Agreements
Milestone payments		$ 3.3	$ 2.2
Acquired in-process research and development						$ 9.4
Number of INDs \| item				2
Number of additional undisclosed targets \| item					3
Research and development expense										$ 2.1
Percentage of royalty on net sales									6.00%
License Agreement Terms \| License Agreements Licensor Pfizer \| Rucaparib
License Agreements
Upfront payment							$ 7.0
Milestones paid to Pfizer prior to FDA approval							$ 1.4
Milestone payments											$ 82.5
License Agreement Terms \| Advenchen Laboratories LLC \| License Agreements Lucitanib
License Agreements
Percentage of non-royalty consideration payable on sublicense agreements								25.00%
Milestone payment obligation	$ 65.0