XML 68 R54.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Restructuring - Schedule of Restructuring and Related Expenses (Details) $ in Millions | Mar. 31, 2017 USD ($)
--- | ---
Restructuring Cost and Reserve [Line Items] |
Estimated Remaining Costs | $ 606
2017 Plan |
Restructuring Cost and Reserve [Line Items] |
First Quarter 2017 | 144
Expected total cost | 750
Workforce reduction | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
First Quarter 2017 | 103
Estimated Remaining Costs | 104
Expected total cost | 207
Technology rationalization | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
First Quarter 2017 | 3
Estimated Remaining Costs | 143
Expected total cost | 146
Lease consolidation | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
First Quarter 2017 | 3
Estimated Remaining Costs | 173
Expected total cost | 176
Asset impairments | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
First Quarter 2017 | 13
Estimated Remaining Costs | 27
Expected total cost | 40
Other Restructuring | 2017 Plan |
Restructuring Cost and Reserve [Line Items] |
First Quarter 2017 | 22
Estimated Remaining Costs | 159
Expected total cost | $ 181

X
- Definition Amount of costs incurred to date for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 + Details
Name: | us-gaap_RestructuringAndRelatedCostCostIncurredToDate1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount expected to be recognized in earnings for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 + Details
Name: | us-gaap_RestructuringAndRelatedCostExpectedCost1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of expected cost remaining for the specified restructuring cost. + References No definition available. + Details
Name: | us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_RestructuringCostAndReserveLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RestructuringPlanAxis=aon_A2017PlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringCostAndReserveAxis=us-gaap_EmployeeSeveranceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringCostAndReserveAxis=aon_TechnologyRationalizationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringCostAndReserveAxis=aon_RealEstateRealizationCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringCostAndReserveAxis=aon_AssetImpairmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringCostAndReserveAxis=us-gaap_OtherRestructuringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |