Segment Information (Tables)

3 Months Ended

Mar. 31, 2016

Segment Reporting [Abstract]

Schedule of total revenue by business segments

Aon's total revenue is as follows (in millions):

	Three months ended March 31,
	2016			2015
Risk Solutions	$	1,872		$	1,895
HR Solutions	930			970
Intersegment eliminations	(10		)	(18		)
Total revenue	$	2,792		$	2,847

Schedule of commissions, fees and other revenues by products

Commissions, fees and other revenues by product are as follows (in millions):

	Three months ended March 31,
	2016			2015
Retail brokerage	$	1,495		$	1,513
Reinsurance brokerage	372			377
Total Risk Solutions Segment	1,867			1,890
Consulting services	374			371
Outsourcing	560			604
Intrasegment	(4		)	(5		)
Total HR Solutions Segment	930			970
Intersegment	(10		)	(18		)
Total commissions, fees and other revenue	$	2,787		$	2,842

Schedule of fiduciary investment income by business segments

Fiduciary investment income by segment is as follows (in millions):

	Three months ended March 31,
	2016		2015
Risk Solutions	$	5	$	5
HR Solutions	—		—
Total fiduciary investment income	$	5	$	5

Schedule of reconciliation of segment income before tax to income from continuing operations before income taxes

A reconciliation of segment operating income before tax to income before income taxes is as follows (in millions):

	Three months ended March 31,
	2016			2015
Risk Solutions	$	429		$	412
HR Solutions	67			76
Segment income before income taxes	496			488
Unallocated expenses	(46		)	(47		)
Interest income	2			3
Interest expense	(69		)	(65		)
Other income	18			42
Income before income taxes	$	401		$	421