Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Prospectus Date	rr_ProspectusDate	Jan. 31, 2011
Limited Duration Portfolio (Prospectus Summary): \| Limited Duration Portfolio
Risk/Return:	rr_RiskReturnAbstract
Supplement Text	ck0000741375_SupplementTextBlock	Prospectus Supplement May 10, 2010 Morgan Stanley Institutional Fund Trust Supplement dated May 10, 2011 to the Morgan Stanley Institutional Fund Trust Prospectus dated January 31, 2011 of: Limited Duration Portfolio The following disclosure is hereby added as the first sentence of the third paragraph in the section of the Prospectus titled "Portfolio Summary—Principal Investment Strategies": The Portfolio may invest in high yield securities (commonly referred to as "junk bonds"). The following disclosure is hereby added following the third paragraph in the section of the Prospectus titled "Fund Summary—Principal Risks": • *High Yield Securities.* The Portfolio's investments in high yield securities expose it to a substantial degree of credit risk. High yield securities may be issued by companies that are restructuring, are smaller and less creditworthy or are more highly indebted than other companies, and therefore they may have more difficulty making scheduled payments of principal and interest. High yield securities may experience reduced liquidity, and sudden and substantial decreases in price. Please retain this supplement for future reference. IFTFISPT 5/11
Investment Strategy, Heading	rr_StrategyHeading	The following disclosure is hereby added as the first sentence of the third paragraph in the section of the Prospectus titled "Portfolio Summary—Principal Investment Strategies":
Investment Strategy, Narrative	rr_StrategyNarrativeTextBlock	The Portfolio may invest in high yield securities (commonly referred to as "junk bonds").
Risk, Heading	rr_RiskHeading	The following disclosure is hereby added following the third paragraph in the section of the Prospectus titled "Fund Summary—Principal Risks":
Risk, Narrative	rr_RiskNarrativeTextBlock	• *High Yield Securities.* The Portfolio's investments in high yield securities expose it to a substantial degree of credit risk. High yield securities may be issued by companies that are restructuring, are smaller and less creditworthy or are more highly indebted than other companies, and therefore they may have more difficulty making scheduled payments of principal and interest. High yield securities may experience reduced liquidity, and sudden and substantial decreases in price.
Limited Duration Portfolio \| Class I Shares
Risk/Return:	rr_RiskReturnAbstract
Trading Symbol	dei_TradingSymbol	MPLDX

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The date of the prospectus.

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Narrative Risk Disclosure.

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Narrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.

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Reference 1: 1
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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.

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