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_
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- Definition

Loss Contingency Damages Awarded Value Excluding Interest and Costs

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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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.

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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
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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Period Type:	instant

- 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 of judgment or settlement awarded to (against) the entity in respect 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.

+ References

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

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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		12 Months Ended
	Mar. 31, 2017 USD ($)	Dec. 20, 2016 GBP (£)	Jun. 29, 2015 NZD	Jan. 26, 2015 USD ($)	Jan. 26, 2015 CHF (SFr)	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)	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)	Apr. 30, 2014 GBP (£)
Legal, Guarantees and Indemnifications
Revenue															$ 2,381,000,000	$ 2,276,000,000
Letters of credit outstanding	$ 90,000,000														90,000,000		$ 90,000,000
Maximum potential funding under commitments	64,000,000														64,000,000		95,000,000
Potential Claim for Pension Advisory Services
Legal, Guarantees and Indemnifications
Estimate of possible loss	56,000,000														56,000,000			£ 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	46,000,000									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	9,000,000				SFr 8,700,000.0
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				$ 115,000
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	87,000,000														87,000,000
Damages sought \| £		£ 70
Pending Litigation \| Lyttleton Port Company Limited
Legal, Guarantees and Indemnifications
Damages sought	129,000,000		NZD 184
Minimum
Legal, Guarantees and Indemnifications
Estimate of possible loss	0														0
Maximum
Legal, Guarantees and Indemnifications
Estimate of possible loss	$ 200,000,000														$ 200,000,000
Aviation and Aerospace Broking Industry
Legal, Guarantees and Indemnifications
Revenue																	$ 100,000,000