XML 38 R43.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Acquisitions and Dispositions - Dispositions (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2015 | Mar. 31, 2014
Dispositions |  |
Gain on disposal of business | $ 19.0 us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal | $ 0 us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal
Risk Solutions [Member] |  |
Dispositions |  |
Number of dispositions | 1 aon_NumberOfDispositions / us-gaap_StatementBusinessSegmentsAxis = aon_RiskAndInsuranceBrokerageServicesMember | 1 aon_NumberOfDispositions / us-gaap_StatementBusinessSegmentsAxis = aon_RiskAndInsuranceBrokerageServicesMember
Gain on disposal of business |  | $ 1.0 us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal / us-gaap_StatementBusinessSegmentsAxis = aon_RiskAndInsuranceBrokerageServicesMember
HR Solutions [Member] |  |
Dispositions |  |
Number of dispositions | 1 aon_NumberOfDispositions / us-gaap_StatementBusinessSegmentsAxis = aon_ConsultingMember |

X
- Definition Represents the number of entities disposed of by the reporting entity. + References No definition available. + Details
Name: | aon_NumberOfDispositions
Namespace Prefix: | aon_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2443-110228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51719941&loc=d3e2941-110230 + Details
Name: | us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=aon_ConsultingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=aon_RiskAndInsuranceBrokerageServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |