Rendering

Component: (Network and Table)
Network
2413406 - Disclosure - Income Taxes - Reconciliation of the beginning and ending amount of unrecognized tax benefits (Details)
(http://www.aon.com/role/IncomeTaxesReconciliationOfBeginningAndEndingAmountOfUnrecognizedTaxBenefitsDetails)
Table(Implied)
Slicers (applies to each fact value in each table cell)
Reporting Entity [Axis]0000315293 (http://www.sec.gov/CIK)
Income Tax Disclosure [Abstract]Period [Axis]
2016-01-01 - 2016-12-31
2015-01-01 - 2015-12-31
Income Tax Disclosure [Abstract]
 
 
Reconciliation of the Company's beginning and ending amount of unrecognized tax benefits
 
 
Balance at the beginning of the period
238,000,000  
211,000,000  
Additions based on tax positions related to the current year
36,000,000  
31,000,000  
Additions for tax positions of prior years
20,000,000  
53,000,000  
Reductions for tax positions of prior years
(12,000,000) 
(18,000,000) 
Settlements
0  
(32,000,000) 
Business combinations
2,000,000  
0  
Lapse of statute of limitations
(5,000,000) 
(5,000,000) 
Foreign currency translation
(1,000,000) 
(2,000,000) 
Balance at the end of the period
278,000,000  
 
238,000,000