Revenue (Tables)

12 Months Ended

Dec. 31, 2019

Revenue from Contract with Customer [Abstract]

Disaggregation of revenue

The following schedule disaggregates various components of the Company's revenue:

	Twelve Months Ended December 31,
	2019		2018		2017
Marsh:
EMEA	$	2,482	$	2,132	$	2,033
Asia Pacific	953		683		645
Latin America	460		400		404
Total International	3,895		3,215		3,082
U.S./Canada	4,119		3,662		3,322
Total Marsh	8,014		6,877		6,404
Guy Carpenter	1,480		1,286		1,187
Subtotal	9,494		8,163		7,591
Fiduciary interest income	105		65		39
Total Risk and Insurance Services	$	9,599	$	8,228	$	7,630
Mercer:
Wealth	$	2,369	$	2,185	$	2,148
Health	1,796		1,735		1,648
Career	856		812		732
Total Mercer	5,021		4,732		4,528
Oliver Wyman	2,122		2,047		1,916
Total Consulting	$	7,143	$	6,779	$	6,444

Contract assets and liabilities

The following schedule provides contract assets and contract liabilities information from contracts with customers.

(In millions)	December 31, 2019		December 31, 2018		January 1, 2018
Contract Assets	$	207	$	112	$	128
Contract Liabilities	$	593	$	545	$	583