Label	Element	Value
PAX WORLD BALANCED FUND
Risk/Return:	rr_RiskReturnAbstract
Supplement [Text Block]	ck0000076721_SupplementTextBlock	Pax World Funds Series Trust I Pax World Balanced Fund Supplement Dated January 2, 2015 to the Prospectus Dated June 4, 2014 Effective January 2, 2015, the Prospectus is amended, as follows: Page 7
Risk/Return [Heading]	rr_RiskReturnHeading	PAX WORLD BALANCED FUND
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The third paragraph under Principal Investment Strategies is replaced in its entirety with the following: With respect to the equity portion of its portfolio, the Balanced Fund’s portfolio managers seek to manage a high conviction, core growth portfolio of primarily large cap securities with a smaller allocation to core, mid- and small-cap securities of high quality, attractively valued companies. The portfolio managers utilize investment processes combining fundamental analysis with a focus on valuation and volatility reduction.

Principal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.

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

-Publisher SEC

-Name Form

-Number N-1A

-Chapter A

-Section 4

-Subsection a

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