Revenue from Contracts with Customers (Tables)

9 Months Ended

Sep. 30, 2018

Revenue from Contract with Customer [Abstract]

Consolidated revenue from contracts with customers by geographic area, which is attributed on the basis of where the services are performed, is as follows (in millions):



	Three months ended September 30, 2018		Nine months ended September 30, 2018
United States	$	1,215	$	3,456
Americas other than United States	203		683
United Kingdom	264		1,161
Europe, Middle East, & Africa other than United Kingdom	399		1,871
Asia Pacific	268		829
Total revenue	$	2,349	$	8,000

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



	Three months ended September 30, 2018			Nine months ended September 30, 2018
Commercial Risk Solutions	$	1,029		$	3,379
Reinsurance Solutions	279			1,401
Retirement Solutions	501			1,356
Health Solutions	278			1,038
Data & Analytic Services	263			834
Elimination	(1		)	(8		)
Total revenue	$	2,349		$	8,000

Capitalized Contract Cost

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



	Three months ended September 30, 2018			Nine months ended September 30, 2018
Balance at beginning of period ⁽¹⁾	$	144		$	145
Additions	16			37
Amortization	(9		)	(30		)
Impairment	—			—
Foreign currency translation and other	(1		)	(2		)
Balance at end of period	$	150		$	150


(1)	Upon adoption of the new revenue recognition standard on January 1, 2018, Aon capitalized $145 million of costs to obtain contracts with customers.

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



	Three months ended September 30, 2018			Nine months ended September 30, 2018
Balance at beginning of period ⁽¹⁾	$	216		$	298
Additions	332			1,043
Amortization	(305		)	(1,090		)
Impairment	—			—
Foreign currency translation and other	5			(3		)
Balance at end of period	$	248		$	248


(1)	Upon adoption of the new revenue recognition standard on January 1, 2018, Aon capitalized $298 million of costs to fulfill contracts with customers.