XML 49 R34.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Goodwill and Other Intangible Assets (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract] |
Schedule of Changes in the Net Carrying Amount of Goodwill by Operating Segment | The changes in the net carrying amount of goodwill for the three months ended March 31, 2018 are as follows (in millions):
Balance as of December 31, 2017 | $ | 8,358 |
Goodwill related to current year acquisitions | 12 |
Goodwill related to prior year acquisitions | 4 |
Foreign currency translation and other | 176 |
Balance as of March 31, 2018 | $ | 8,550 |
Schedule of Other Intangible Assets by Asset Class | Other intangible assets by asset class are as follows (in millions):
| March 31, 2018 |  | December 31, 2017
| Gross Carrying Amount |  | Accumulated Amortization and Impairment |  | Net Carrying Amount |  | Gross Carrying Amount |  | Accumulated Amortization and Impairment |  | Net Carrying Amount
Customer related and contract based | $ | 2,615 |  |  | $ | 1,496 |  |  | $ | 1,119 |  |  | $ | 2,550 |  |  | $ | 1,415 |  |  | $ | 1,135 |
Tradenames | 1,052 |  |  | 589 |  |  | 463 |  |  | 1,047 |  |  | 533 |  |  | 514 |
Technology and other | 426 |  |  | 346 |  |  | 80 |  |  | 416 |  |  | 332 |  |  | 84 |
Total | $ | 4,093 |  |  | $ | 2,431 |  |  | $ | 1,662 |  |  | $ | 4,013 |  |  | $ | 2,280 |  |  | $ | 1,733 |
Schedule of Estimated Future Amortization Expense on Intangible Assets | The estimated future amortization for finite lived intangible assets as of March 31, 2018 is as follows (in millions):
Remainder of 2018 | $ | 332 |
2019 | 430 |
2020 | 252 |
2021 | 151 |
2022 | 101 |
Thereafter | 396 |
Total | $ | 1,662 |

X
- Definition Tabular disclosure of the class of other intangible assets, which includes finite and indefinite-lived intangible assets. + References No definition available. + Details
Name: | aon_ScheduleOfFiniteAndIndefiniteLivedIntangibleAssetsTableTextBlock
Namespace Prefix: | aon_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 + Details
Name: | us-gaap_ScheduleOfGoodwillTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the amount of amortization expense expected to be recorded in succeeding fiscal years for finite-lived intangible assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
Name: | us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration