Document and Entity Information	12 Months Ended
Dec. 31, 2011
Document and Entity Information
Entity Registrant Name	Aon plc
Entity Central Index Key	0000315293
Document Type	8-K
Document Period End Date	Dec. 31, 2011
Amendment Flag	false

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If the value is true, then the document as an amendment to previously-filed/accepted document.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The type of document being provided (such as 10-K, 10-Q, N-1A, etc). The document type is limited to the same value as the supporting SEC submission type, minus any "/A" suffix. The acceptable values are as follows: S-1, S-3, S-4, S-11, F-1, F-3, F-4, F-9, F-10, 6-K, 8-K, 10, 10-K, 10-Q, 20-F, 40-F, N-1A, 485BPOS, 497, NCSR, N-CSR, N-CSRS, N-Q, 10-KT, 10-QT, 20-FT, POS AM and Other.

+ References

No definition available.

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- Definition

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

-Publisher SEC

-Name Regulation 12B

-Number 240

-Section 12b

-Subsection 1

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- Definition

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

+ References

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

-Publisher SEC

-Name Regulation 12B

-Number 240

-Section 12b

-Subsection 1

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