Term Receivables and Trade Accounts Receivable - Additional Information (Details)	12 Months Ended
Jan. 31, 2017
Disclosure Term Receivables And Trade Accounts Receivable Additional Information [Abstract]
Billing period	30 days

Disclosure - Term Receivables and Trade Accounts Receivable - Additional Information [Abstract]

No definition available.

Name:	ment_DisclosureTermReceivablesAndTradeAccountsReceivableAdditionalInformationAbstract
Namespace Prefix:	ment_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration