Employee Benefits (Tables)

9 Months Ended

Sep. 30, 2019

Retirement Benefits [Abstract]

Components of net periodic benefit cost for the pension plans

The following table provides the components of the net periodic (benefit) cost recognized in the Condensed Consolidated Statements of Income for Aon’s significant U.K., U.S., and other major pension plans, which are located in the Netherlands and Canada. Service cost is reported in Compensation and benefits and all other components are reported in Other income (expense) as follows (in millions):

	Three Months Ended September 30
	U.K.						U.S.						Other
	2019			2018			2019			2018			2019			2018
Service cost	$	—		$	—		$	—		$	—		$	—		$	—
Interest cost	26			26			27			24			6			6
Expected return on plan assets, net of administration expenses	(46		)	(46		)	(34		)	(36		)	(9		)	(11		)
Amortization of prior-service cost	—			1			1			—			—			—
Amortization of net actuarial loss	7			6			13			15			3			3
Net periodic (benefit) cost	(13		)	(13		)	7			3			—			(2		)
Loss on pension settlement	—			9			—			—			—			—
Total net periodic (benefit) cost	$	(13	)	$	(4	)	$	7		$	3		$	—		$	(2	)

	Nine Months Ended September 30
	U.K.						U.S.						Other
	2019			2018			2019			2018			2019			2018
Service cost	$	—		$	—		$	—		$	—		$	—		$	—
Interest cost	81			84			81			74			20			20
Expected return on plan assets, net of administration expenses	(143		)	(147		)	(102		)	(108		)	(29		)	(34		)
Amortization of prior-service cost	1			1			2			1			—			—
Amortization of net actuarial loss	22			21			40			45			9			9
Net periodic (benefit) cost	(39		)	(41		)	21			12			—			(5		)
Loss on pension settlement	—			32			—			—			—			—
Total net periodic (benefit) cost	$	(39	)	$	(9	)	$	21		$	12		$	—		$	(5	)

Schedule of employer's contributions

The following table summarizes contributions made to the Company’s significant pension plans (in millions):

	Three Months Ended September 30				Nine Months Ended September 30
	2019		2018		2019		2018
Contributions to U.K. pension plans	$	19	$	27	$	65	$	75
Contributions to U.S. pension plans (1)	7		108		30		133
Contributions to other major pension plans	3		3		13		14
Total contributions	$	29	$	138	$	108	$	222

(1)

Includes the Company’s contribution to the qualified U.S. pension plan of $100 million for the three and nine months ended September 30, 2018, which allowed the pension contribution tax deduction to be taken at the 2017 federal tax rate of 35%.