XML 32 R67.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Fair Value Measurements and Financial Instruments Schedule of assets and liabilities that are measured at fair value on a recurring basis (Details) (USD $) | 3 Months Ended | 9 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Money market funds and highly liquid debt securities | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Money market funds and highly liquid debt securities | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Money market funds [Member] | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Money market funds [Member] | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Highly liquid debt securities [Member] | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Highly liquid debt securities [Member] | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Corporate bonds [Member] | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Corporate bonds [Member] | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Government bonds [Member] | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Government bonds [Member] | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Equity securities [Member] | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Equity securities [Member] | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Interest rate contracts [Member] | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Interest rate contracts [Member] | Sep. 30, 2014 Recurring [Member] Fair Value [Member] Foreign exchange contracts [Member] | Dec. 31, 2013 Recurring [Member] Fair Value [Member] Foreign exchange contracts [Member] | Sep. 30, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Money market funds and highly liquid debt securities | Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Money market funds and highly liquid debt securities | Sep. 30, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Corporate bonds [Member] | Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Corporate bonds [Member] | Sep. 30, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Government bonds [Member] | Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Government bonds [Member] | Sep. 30, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Equity securities [Member] | Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Equity securities [Member] | Sep. 30, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Interest rate contracts [Member] | Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Interest rate contracts [Member] | Sep. 30, 2014 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Foreign exchange contracts [Member] | Dec. 31, 2013 Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Foreign exchange contracts [Member] | Sep. 30, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Money market funds and highly liquid debt securities | Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Money market funds and highly liquid debt securities | Sep. 30, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Corporate bonds [Member] | Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Corporate bonds [Member] | Sep. 30, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Government bonds [Member] | Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Government bonds [Member] | Sep. 30, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Equity securities [Member] | Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Equity securities [Member] | Sep. 30, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Interest rate contracts [Member] | Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Interest rate contracts [Member] | Sep. 30, 2014 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Foreign exchange contracts [Member] | Dec. 31, 2013 Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Foreign exchange contracts [Member] | Sep. 30, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Money market funds and highly liquid debt securities | Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Money market funds and highly liquid debt securities | Sep. 30, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Corporate bonds [Member] | Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Corporate bonds [Member] | Sep. 30, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Government bonds [Member] | Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Government bonds [Member] | Sep. 30, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Equity securities [Member] | Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Equity securities [Member] | Sep. 30, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Interest rate contracts [Member] | Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Interest rate contracts [Member] | Sep. 30, 2014 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Foreign exchange contracts [Member] | Dec. 31, 2013 Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Foreign exchange contracts [Member]
Fair Value Disclosures [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net assets value (in dollar per share) |  | $ 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Realized gain | $ 6,000,000 |  | $ 6,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrealized gain (loss) | 0 |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Money market funds and highly liquid debt securities |  |  |  | 1,649,000,000 | [1] | 2,079,000,000 | [2] | 1,647,000,000 | 2,054,000,000 | 2,000,000 | 25,000,000 |  |  |  |  |  |  |  |  |  |  | 1,647,000,000 | [1] | 2,054,000,000 | [2] |  |  |  |  |  |  |  |  |  |  | 2,000,000 | [1] | 25,000,000 | [2] |  |  |  |  |  |  |  |  |  |  | 0 | [1] | 0 | [2] |  |  |  |  |  |  |  |  |  |
Other investments |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 | 2,000,000 | 7,000,000 | 7,000,000 | 11,000,000 | 13,000,000 |  |  |  |  |  |  |  |  | 0 | 0 | 0 | 0 | 6,000,000 | 6,000,000 |  |  |  |  |  |  |  |  | 0 | 0 | 7,000,000 | 7,000,000 | 5,000,000 | 7,000,000 |  |  |  |  |  |  |  |  | 1,000,000 | 2,000,000 | 0 | 0 | 0 | 0 |  |  |  |
Derivatives |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 9,000,000 | 55,000,000 | 71,000,000 |  |  |  |  |  |  |  |  |  |  | 0 | 0 | 0 | 0 |  |  |  |  |  |  |  |  |  |  | 0 | 9,000,000 | 55,000,000 | 71,000,000 |  |  |  |  |  |  |  |  |  |  | 0 | 0 | 0 | 0
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 65,000,000 | $ 93,000,000 |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  | $ 65,000,000 | $ 93,000,000 |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0
[1] | Includes $1,647 million of money market funds and $2 million of highly liquid debt securities that are classified as Fiduciary assets, Short-term investments or Cash and cash equivalents in the Condensed Consolidated Statements of Financial Position, depending on their nature and initial maturity. See Note 8 "Investments" for additional information regarding the Company's investments.
[2] | Includes $2,054 million of money market funds and $25 million of highly liquid debt securities that are classified as Fiduciary assets, Short-term investments or Cash and cash equivalents in the Condensed Consolidated Statements of Financial Position, depending on their nature and initial maturity. See Note 8 "Investments" for additional information regarding the Company's investments.

X
- Definition Represents the fair value of money market funds and other highly liquid securities. + References No definition available. + Details
Name: | aon_BasisMoneyMarketFundsAndHighlyLiquidSecuritiesFairValueDisclosure
Namespace Prefix: | aon_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Represents the fund net assets value of an entity. + References No definition available. + Details
Name: | aon_FairValueInvestmentsFundNetAssetsFairValue
Namespace Prefix: | aon_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of unrealized gain (loss) on investments in debt and equity securities classified as available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 + Details
Name: | us-gaap_AvailableforsaleSecuritiesGrossUnrealizedGainLoss1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226008-175313 + Details
Name: | us-gaap_DerivativeAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226008-175313 + Details
Name: | us-gaap_DerivativeLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

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

X
- Definition Other investments not otherwise specified in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 12 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph g -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(f,g)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
Name: | us-gaap_OtherInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant