We maintain qualified and nonqualified defined benefit retirement plans covering certain current and former U.S. and European employees, retirement savings plans covering eligible U.S. and U.K. employees and certain postretirement health care and life insurance benefit plans covering eligible U.S. retirees. We also participate in a union sponsored multi-employer pension plan covering certain U.S. employees with union affiliations.

Net periodic benefit costs of our defined benefit retirement plans for the quarter and six months ended June 30, 2020 and 2019 were as follows:

	Quarter Ended June 30,				Six Months Ended June 30,
(In millions)	2020		2019		2020		2019
U.S. Nonqualified Defined Benefit Retirement Plans
Service cost	$	0.3	$	0.3	$	0.6	$	0.6
Interest cost		0.1		0.1		0.2		0.3
Net amortization		0.1	—			0.2	—
Net periodic benefit cost	$	0.5	$	0.4	$	1.0	$	0.9

(In millions)	June 30, 2020		December 31, 2019
Amounts recognized on the balance sheet for U.S. nonqualified defined benefit retirement plans:
Accrued liabilities	$	1.3	$	1.4
Other non-current liabilities		19.4		18.9
Total accrued benefit	$	20.7	$	20.3

	Quarter Ended June 30,						Six Months Ended June 30,
(In millions)	2020			2019			2020			2019
European Defined Benefit Retirement Plans
Service cost	$	0.3		$	0.2		$	0.5		$	0.5
Interest cost		0.8			1.1			1.7			2.2
Expected return on plan assets		(1.7	)		(2.2	)		(3.4	)		(4.4	)
Net amortization and deferral		0.1			0.1			0.2			0.2
Net periodic benefit credit	$	(0.5	)	$	(0.8	)	$	(1.0	)	$	(1.5	)

(In millions)	June 30, 2020		December 31, 2019
Amounts recognized on the balance sheet for European defined benefit retirement plans:
Other assets	$	45.7	$	45.2

Accrued liabilities		1.7		0.6
Other non-current liabilities		19.3		18.9
Total accrued benefit	$	21.0	$	19.5

All costs related to our pensions are included as a component of operating income in our condensed consolidated statements of operations. For the quarters ended June 30, 2020 and 2019, amounts unrelated to service costs were a benefit of $0.6 million and $0.9 million, respectively. For the six months ended June 30, 2020 and 2019, amounts unrelated to service costs were a benefit of $1.1 million and $1.7 million, respectively.

We generally fund our U.S. non-qualified defined benefit retirement plans when benefit payments are incurred. We have contributed approximately $0.3 million in the first six months of 2020 to cover unfunded benefits. We expect to contribute a total of $1.4 million in 2020 to cover unfunded benefits. We contributed $0.3 million to our U.S. non-qualified defined benefit retirement plans during the first six months of 2019.

We contributed $1.9 million and $2.3 million to our European defined benefit retirement plans during the six months ended June 30, 2020 and 2019, respectively. We plan to contribute approximately $5.0 million during 2020 to our European plans.

We recorded $0.2 million of net amortization gain deferral for both the quarters ended June 30, 2020 and 2019; and $0.5 million for both the six months ended June 30, 2020 and 2019. Net periodic benefit costs of our postretirement health care and life insurance benefit plans for the quarter and six months ended June 30, 2020 and 2019 were immaterial.

(In millions)	June 30, 2020		December 31, 2019
Amounts recognized on the balance sheet:
Accrued liabilities	$	0.5	$	0.5
Other non-current liabilities	2.6		2.6
Total accrued benefit	$	3.1	$	3.1

Amounts contributed in connection with our postretirement plans were immaterial for both the six months ended June 30, 2020 and 2019. We periodically fund our postretirement plans to pay covered expenses as they are incurred. We expect to contribute less than $0.5 million in 2020 to cover unfunded benefits.