Investment Objectives and Goals	Jun. 30, 2025
Prospectus [Line Items]
Registrant Name	Impax Funds Series Trust I
Document Period End Date	Jun. 30, 2025

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

No definition available.

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