Name:	ovas_AccruedLegalAuditAndTaxServicesCurrent
Namespace Prefix:	ovas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees and consultancy fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle, if longer).

No definition available.

Name:	ovas_AccruedProfessionalAndConsultantFeesCurrent
Namespace Prefix:	ovas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the carrying value as of the balance sheet date of obligations incurred through that date and payable for the obligations related to development, site costs and contract manufacturing. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle, if longer).

No definition available.

Name:	ovas_DevelopmentSiteCostsAndContractManufacturing
Namespace Prefix:	ovas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of expenses incurred but not yet paid classified as other except deferred rent, due within one year or the normal operating cycle, if longer

No definition available.

Name:	ovas_OtherAccruedLiabilitiesExcludingDeferredRentCurrent
Namespace Prefix:	ovas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_AccruedLiabilitiesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707

Name:	us-gaap_DeferredRentCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_EmployeeRelatedLiabilitiesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.