Retirement Plans (Tables)

3 Months Ended

Mar. 31, 2018

Retirement Benefits [Abstract]

Net Pension Income or Postretirement Expense

Net pension expense (income) for our domestic and foreign plans was as follows:

	Three Months Ended
	March 31,		March 31,
	2018		2017
Net pension expense (income)	$	79	$	(433	)

The components of net pension expense (income) for our domestic and foreign plans include the following: 

	DomesticPension Plans						Foreign Pension Plans
	Three Months Ended						Three Months Ended
	March 31,			March 31,			March 31,			March 31,
	2018			2017			2018			2017
Service cost	$	—		$	—		$	11		$	12
Interest cost	1,781			2,068			11			8
Expected return on plan assets (1)	(3,225		)	(4,061		)	(7		)	(5		)
Amortization of loss	1,466			1,446			42			38
Other cost due to retirement	—			61			—			—
Expense (income), net	$	22		$	(486	)	$	57		$	53

(1) Expected return on plan assets is net of expected investment expenses and certain administrative expenses.

Net post-retirement expense for our other post-retirement plan includes the following components:

	Three Months Ended
	March 31,			March 31,
	2018			2017
Service cost	$	1		$	1
Interest cost	39			40
Amortization of gain	(12		)	(25		)
Post-retirement expense	$	28		$	16