Note 10—Benefit Plans and Other Postretirement Benefits

The Company and certain of its domestic subsidiaries have defined benefit pension plans (the “U.S. Plans”), which cover certain U.S. employees and which represent the majority of the plan assets and benefit obligations of the aggregate defined benefit plans of the Company. The U.S. Plans’ benefits are generally based on years of service and compensation and are generally noncontributory. Certain U.S. employees not covered by the U.S. Plans are covered by defined contribution plans. Certain foreign subsidiaries have defined benefit plans covering their employees (the “International Plans” and, together with the U.S. Plans, the “Plans”). The following is a summary, based on the most recent actuarial valuations of the Company’s net cost for pension benefits, of the Plans and other postretirement benefits for the three and nine months ended September 30, 2017 and 2016:


					Other Postretirement
	Pension Benefits				Benefits
Three Months Ended September 30:	2017		2016		2017		2016
Service cost	$	2.5	$	2.3	$	—	$	—
Interest cost		5.0		5.2		0.1		0.1
Expected return on plan assets		(7.8)		(7.6)		—		—
Amortization of prior service cost		0.7		0.6		—		—
Amortization of net actuarial losses		5.8		5.6		0.2		0.2
Net pension expense	$	6.2	$	6.1	$	0.3	$	0.3

Nine Months Ended September 30:
Service cost	$	7.3	$	6.9	$	—	$	0.1
Interest cost		14.9		15.8		0.3		0.3
Expected return on plan assets		(23.2)		(22.7)		—		—
Amortization of transition obligation		—		(0.1)		—		—
Amortization of prior service cost		2.1		1.7		—		—
Amortization of net actuarial losses		17.2		16.7		0.5		0.5
Net pension expense	$	18.3	$	18.3	$	0.8	$	0.9

During the nine months ended September 30, 2017, the Company made cash contributions of approximately $17.0 to the U.S. Plans, and estimates that, based on current actuarial calculations, it will make aggregate cash contributions to the Plans in 2017 of approximately $25.0, the majority of which will be to the U.S. Plans. The timing and amount of cash contributions in subsequent years will depend on a number of factors, including the investment performance of the Plans’ assets.

The Company offers various defined contribution plans for certain U.S. and foreign employees. Participation in these plans is based on certain eligibility requirements. The Company matches the majority of employee contributions to U.S. defined contribution plans with cash contributions up to a maximum of 5% of eligible compensation. During the nine months ended September 30, 2017 and 2016, the total matching contributions to the U.S. defined contribution plans were approximately $5.0 and $3.5, respectively.