Name:	ment_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitiesValueInterestExpense
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The change in the estimated liability for contingent consideration resulting in a gain or loss in the statement of operations during the reporting period.

No definition available.

Name:	ment_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValueChangeInEstimate
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This represents new contingent consideration arising from a contingency assumed in a business combination during the reporting period.

No definition available.

Name:	ment_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValueContingentConsideration
Namespace Prefix:	ment_
Data Type:	xbrli:monetaryItemType
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- Details

Name:	us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258