Revenue from Contracts with Customers (Tables)

3 Months Ended

Mar. 31, 2018

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

Consolidated Revenue by geographic area, which is attributed on the basis of where the services are performed, is as follows (in millions):

	Three months ended March 31, 2018
United States	$	1,116
Americas other than United States	237
United Kingdom	484
Europe, Middle East, & Africa other than United Kingdom	979
Asia Pacific	274
Total revenue	$	3,090

The following table summarizes revenue from contracts with customers by principal service line (in millions):

	Three months ended March 31, 2018
Commercial Risk Solutions	$	1,184
Reinsurance Solutions	742
Retirement Solutions	424
Health Solutions	451
Data & Analytic Services	294
Elimination	(5		)
Total revenue	$	3,090

Capitalized Contract Cost

The changes in the net carrying amount of capitalized cost to fulfill contracts with customers are as follows (in millions):

	Three months ended March 31, 2018
Balance at beginning of period	$	298
Additions	370
Amortization	(432		)
Impairment	—
Foreign currency translation and other	4
Balance at end of period	$	240

The changes in the net carrying amount of capitalized cost to obtain contracts with customers are as follows (in millions):

	Three months ended March 31, 2018
Balance at beginning of period	$	145
Additions	8
Amortization	(10		)
Impairment	—
Foreign currency translation and other	1
Balance at end of period	$	144