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Portion of the fair value of potential payments under contingent consideration arrangements, including cash and shares as applicable, which could be paid beyond the next 12 months.

No definition available.

Name:	ment_ContingentConsiderationAtFairValueNoncurrent
Namespace Prefix:	ment_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	ment_DisclosureFairValueMeasurementAdditionalInformationAbstract
Namespace Prefix:	ment_
Data Type:	xbrli:stringItemType
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Period Type:	duration

Carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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Sum of the carrying values as of the balance sheet date of the portions of all long-term notes and loans payable due within one year or the 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 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20

-Article 5

Name:	us-gaap_NotesAndLoansPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Fair value portion of notes payable.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20,22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682