Name:	cpst_CommitmentsAndContingenciesOtherDisclosuresAbstract
Namespace Prefix:	cpst_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Represents the contribution of other party towards research, development and testing project.

No definition available.

Name:	cpst_ContributionToBeMadeByOtherPartyTowardsResearchDevelopmentAndTestingProject
Namespace Prefix:	cpst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the cumulative amount billed to other party under research, development and testing of project.

No definition available.

Name:	cpst_CumulativeAmountOfBillToOtherPartyTowardsResearchDevelopmentAndTestingProject
Namespace Prefix:	cpst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Represents the number of derivative actions filed during the period.

No definition available.

Name:	cpst_NumberOfDerivativeActionsFiled
Namespace Prefix:	cpst_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the period of contract with other party under research, development and testing of project.

No definition available.

Name:	cpst_PeriodOfContract
Namespace Prefix:	cpst_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the cost of research, development and testing project.

No definition available.

Name:	cpst_ProjectedCostOfResearchDevelopmentAndTestingProject
Namespace Prefix:	cpst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the research and development expense to be incurred by the entity.

No definition available.

Name:	cpst_ResearchAndDevelopmentExpenseToBeIncurredByEntity
Namespace Prefix:	cpst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Number of pending claims pertaining to a loss contingency.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Name:	us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

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.

No definition available.