Pension and Other Postretirement Employee Benefit Plans

The following table details the components of net periodic cost of our company-sponsored pension and other postretirement employee benefit, or OPEB, plans for the periods presented:



	Three Months Ended June 30,
(In thousands)	2019			2018			2019		2018
	Pension Benefit Plans						Other Postretirement Employee Benefit Plans
Service cost	$	669		$	461		$	20	$	20
Interest cost	3,102			3,010			752		611
Expected return on plan assets	(4,132		)	(4,247		)	—		—
Amortization of prior service cost (credit)	—			—			—		(419		)
Amortization of actuarial loss (gain)	1,776			2,458			33		(226		)
Net periodic cost (benefit)	$	1,415		$	1,682		$	805	$	(14	)



	Six Months Ended June 30,
(In thousands)	2019			2018			2019			2018
	Pension Benefit Plans						Other Postretirement Employee Benefit Plans
Service cost	$	1,219		$	895		$	45		$	68
Interest cost	6,223			6,010			1,399			1,218
Expected return on plan assets	(8,267		)	(8,501		)	—			—
Amortization of prior service cost (credit)	—			—			—			(838		)
Amortization of actuarial loss (gain)	3,685			5,028			(195		)	(451		)
Net periodic cost (benefit)	$	2,860		$	3,432		$	1,249		$	(3	)

During the six months ended June 30, 2019 and 2018, we made no contributions to our qualified pension plans. We do not expect, nor are we required, to make contributions in 2019.

During the six months ended June 30, 2019, we made contributions of $0.2 million to our company-sponsored non-qualified pension plan. We estimate contributions will total $0.4 million in 2019. We do not anticipate funding our OPEB plans in 2019 except to pay benefit costs as incurred during the year by plan participants.

During each of the three months ended June 30, 2019 and 2018, pension and OPEB changes in accumulated other comprehensive loss, net of tax, in our Consolidated Balance Sheets totaled $1.3 million. During the six months ended June 30, 2019 and 2018, pension and OPEB changes in accumulated other comprehensive loss, net of tax, in our Consolidated Balance Sheets totaled $2.6 million and $2.8 million, respectively. Refer to the Consolidated Statements of Stockholders' Equity for additional information.