11.

Defined Benefit Plans

The components of net periodic benefit cost for pension and postretirement benefits for the nine and three months ended September 30, 2017 and 2016 were as follows:


(In millions)	Nine Months Ended September 30,
	Pension Benefits						Postretirement Benefits
	2017			2016			2017			2016
Service cost	$	0.4		$	7.2		$	—		$	—
Interest cost		25.0			25.8			—			0.2
Expected return on plan assets		(28.0	)		(27.9	)		—			—
Recognition of prior service costs (credits)		—			—			(5.1	)		(10.0	)
Recognition of actuarial losses (gains)		0.3			—			(1.6	)		1.9

Net periodic benefit (income) cost	$	(2.3	)	$	5.1		$	(6.7	)	$	(7.9	)

(In millions)	Three Months Ended September 30,
	Pension Benefits						Postretirement Benefits
	2017			2016			2017			2016
Service cost		$0.1			$1.6			$—			$—
Interest cost		8.3			8.4			—			(0.1)
Expected return on plan assets		(9.3)			(8.9)			—			—
Recognition of prior service costs (credits)		—			—			—			(3.8)
Recognition of actuarial losses (gains)		0.3			—			(1.6)			1.0

Net periodic benefit (income) cost	$	(0.6	)	$	1.1		$	(1.6	)	$	(2.9	)

Service cost for 2017 relates to benefit accruals in an hourly Union defined benefit plan in our Security segment. All other defined benefit pension plans were frozen as of December 31, 2016.