The maximum number of patients in treatment arm under collaboration agreement.

No definition available.

Name:	crvs_CollaborationAgreementMaximumNumberOfPatientsInTreatmentArm
Namespace Prefix:	crvs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The aggregate potential amount of payments the entity may be required to make to the counterparty based on achievement of milestones under the license or collaboration agreement.

+ References

No definition available.

+ Details

Name:	crvs_LicenseAndCollaborationAgreementsAggregatePotentialMilestonePayments
Namespace Prefix:	crvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of payments to the entity that are required to be made to the counterparty based on achievement of milestones under the license or collaboration agreement.

+ References

No definition available.

+ Details

Name:	crvs_LicenseAndCollaborationAgreementsMilestonePaymentsMade
Namespace Prefix:	crvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum annual fee the entity is obligated to pay to the counterparty under the license or collaboration agreement.

+ References

No definition available.

+ Details

Name:	crvs_LicenseAndCollaborationAgreementsMinimumAnnualFee
Namespace Prefix:	crvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period of written notice the entity is required to provide for termination of the license or collaboration agreement.

+ References

No definition available.

+ Details

Name:	crvs_LicenseAndCollaborationAgreementsPeriodOfWrittenNoticeForTermination
Namespace Prefix:	crvs_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of a one-time cash payment made to the counterparty upon entering into a license or collaboration agreement.

+ References

No definition available.

+ Details

Name:	crvs_LicenseAndCollaborationAgreementsUpfrontCashPaymentMade
Namespace Prefix:	crvs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

- Details

Name:	us-gaap_TypeOfArrangementAxis=crvs_LicenseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=crvs_ScrippsResearchInstituteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_ResearchAndDevelopmentExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=crvs_VernalisRAndDLimitedMember
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:	us-gaap_TypeOfArrangementAxis=crvs_ClinicalTrialCollaborationAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=crvs_GenentechMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

License and Collaboration Agreements (Details)	1 Months Ended	3 Months Ended
License and Collaboration Agreements (Details)	May 31, 2017 item	Mar. 31, 2019 USD ($)	Feb. 28, 2017 USD ($)	Dec. 31, 2016 USD ($)	Feb. 28, 2015 USD ($)
Licensing Agreement \| Scripps Research Institute
License and Collaboration Agreements
Minimum annual fee				$ 25,000
Aggregate potential milestone payments		$ 2,600,000
Milestone payments made		$ 0
Period of written notice to terminate		90 days
Licensing Agreement \| Scripps Research Institute \| Research and development
License and Collaboration Agreements
One-time cash payment				$ 10,000
Licensing Agreement \| Vernalis (R&D) Limited
License and Collaboration Agreements
Milestone payments made			$ 3,000,000
Period of written notice to terminate		90 days
Licensing Agreement \| Vernalis (R&D) Limited \| Minimum
License and Collaboration Agreements
Aggregate potential milestone payments		$ 220,000,000
Licensing Agreement \| Vernalis (R&D) Limited \| Research and development
License and Collaboration Agreements
One-time cash payment					$ 1,000,000
Clinical Trial Collaboration Agreement \| Genentech
License and Collaboration Agreements
Maximum number of patients in treatment arm under collaboration agreement \| item	65