Document and Entity Information	0 Months Ended
Sep. 26, 2013
Risk/Return:
Document Type	497
Document Period End Date	Sep. 26, 2013
Registrant Name	ARIEL INVESTMENT TRUST
Central Index Key	0000798365
Amendment Flag	false
Document Creation Date	Sep. 26, 2013
Document Effective Date	Sep. 26, 2013
Prospectus Date	Feb. 01, 2013
Ariel Fund \| Investor Class
Risk/Return:
Trading Symbol	ARGFX
Ariel Fund \| Institutional Class
Risk/Return:
Trading Symbol	ARAIX
Ariel Appreciation Fund \| Investor Class
Risk/Return:
Trading Symbol	CAAPX
Ariel Appreciation Fund \| Institutional Class
Risk/Return:
Trading Symbol	CAAIX
Ariel Focus Fund \| Investor Class
Risk/Return:
Trading Symbol	ARFFX
Ariel Focus Fund \| Institutional Class
Risk/Return:
Trading Symbol	AFOYX
Ariel Discovery Fund \| Investor Class
Risk/Return:
Trading Symbol	ARDFX
Ariel Discovery Fund \| Institutional Class
Risk/Return:
Trading Symbol	ADYIX

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The date the document was made available and submitted, in CCYY-MM-DD format. The date of submission, date of acceptance by the recipient, and the document effective date are all potentially different.

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The date when a document, upon receipt and acceptance, becomes officially effective, in CCYY-MM-DD format. Usually it is a system-assigned date time value, but it may be declared by the submitter in some cases.

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word "Other".

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

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

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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The date of the prospectus.

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

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