This element represents the amount of coverage as contended by the insurers for the loss.

No definition available.

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Namespace Prefix:	aon_
Data Type:	xbrli:monetaryItemType
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- Definition

Loss Contingency Damages Awarded Value Excluding Interest and Costs

+ References

No definition available.

+ Details

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- Definition

This element represents the difference amount of damages sought by the client after adjusting for amount claimed from insurers.

+ References

No definition available.

+ Details

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- Definition

Loss Contingency, Settlement Agreement, Terms, Maximum Liability

+ References

No definition available.

+ Details

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 4
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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- 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

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- Definition

Amount of damages awarded to the plaintiff in the legal matter.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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Commitments and Contingencies (Details) £ in Millions, NZD in Millions													1 Months Ended				3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017 USD ($)	Dec. 20, 2016 GBP (£)	Jun. 29, 2015 NZD	Jan. 31, 2015 USD ($)	Jan. 26, 2015 USD ($)	Jan. 26, 2015 CHF (SFr)	Dec. 31, 2014 USD ($)	Dec. 02, 2014 USD ($)	Dec. 02, 2014 CHF (SFr)	Sep. 14, 2010 USD ($)	Jun. 01, 2007 USD ($)	Jun. 01, 2007 CHF (SFr)	Aug. 31, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2014 CHF (SFr)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)	Apr. 30, 2014 GBP (£)
Legal, Guarantees and Indemnifications
Revenue																	$ 2,368,000,000	$ 2,282,000,000	$ 4,749,000,000	$ 4,558,000,000
Maximum potential funding under commitments	$ 88,000,000																88,000,000		88,000,000		$ 95,000,000
Letters of credit outstanding	89,000,000																89,000,000		89,000,000		90,000,000
Potential Claim for Pension Advisory Services
Legal, Guarantees and Indemnifications
Estimate of possible loss	57,000,000																57,000,000		57,000,000			£ 45
Opry Mills Mall Limited Partnership
Legal, Guarantees and Indemnifications
Damages sought										$ 200,000,000
Amount of coverage for damages contended by the insurers										50,000,000
Difference amount of damages sought by the client										$ 150,000,000
Damages awarded													$ 204,000,000	$ 200,000,000
International Road Transport Union \| Litigation Award
Legal, Guarantees and Indemnifications
Damages sought	47,000,000											SFr 46,000,000
Damages awarded							$ 28,000,000									SFr 27,900,000
Damages awarded excluding interest and costs	17,000,000								SFr 16,800,000
Case settlement amount				$ 14,000,000		SFr 12,800,000
Settlement, maximum liability	15,000,000					SFr 15,000,000
International Road Transport Union \| Litigation USD Denominated Award
Legal, Guarantees and Indemnifications
Damages sought											$ 3,000,000
Damages awarded															$ 5,000,000
Damages awarded excluding interest and costs								$ 3,100,000
Case settlement amount					$ 4,700,000
Settlement, maximum liability					$ 344,000
International Road Transport Union \| Litigation Expenses and Interest
Legal, Guarantees and Indemnifications
Damages sought											$ 30,000,000
Pending Litigation \| Trustees Of Gleeds Pension Fund 2016
Legal, Guarantees and Indemnifications
Estimate of possible loss	89,000,000																89,000,000		89,000,000
Damages sought \| £		£ 70
Pending Litigation \| Lyttleton Port Company Limited
Legal, Guarantees and Indemnifications
Damages sought	134,000,000		NZD 184
Minimum
Legal, Guarantees and Indemnifications
Estimate of possible loss	0																0		0
Maximum
Legal, Guarantees and Indemnifications
Estimate of possible loss	300,000,000																300,000,000		300,000,000
Aviation and Aerospace Broking Industry
Legal, Guarantees and Indemnifications
Revenue																					$ 100,000,000
Discontinued Operations, Disposed of by Sale \| Tempo Business \| Property Lease Guarantee
Legal, Guarantees and Indemnifications
Guarantor Obligations, Current Carrying Value	39,000,000																39,000,000		39,000,000
Maximum potential funding under commitments	108,000,000																108,000,000		108,000,000
Discontinued Operations, Disposed of by Sale \| Tempo Business \| Performance Guarantee
Legal, Guarantees and Indemnifications
Guarantor Obligations, Current Carrying Value	4,000,000																4,000,000		4,000,000
Maximum potential funding under commitments	$ 401,000,000																$ 401,000,000		$ 401,000,000