Retirement Benefits

3 Months Ended

Mar. 31, 2017

Retirement Benefits [Abstract]

Retirement Benefits

13.RETIREMENT BENEFITS

The Company maintains both qualified and non-qualified defined benefit pension plans and a retiree health plan for its U.S. employees employed prior to April 1, 2010.

Net periodic benefit cost for U.S. employees included the following components for the periods indicated:

Pension Benefits	Three Months Ended
	March 31,
(Dollars in thousands)	2017			2016
Service cost	$	3,299		$	2,897
Interest cost		2,276			2,361
Expected return on plan assets		(3,155	)		(2,484	)
Amortization of net (income) loss		3,040			2,014
Net periodic benefit cost	$	5,460		$	4,788

Other Benefits	Three Months Ended
	March 31,
(Dollars in thousands)	2017			2016
Service cost	$	440		$	438
Interest cost		249			296
Amortization of prior service costs		(33	)		-
Amortization of net (income) loss		76			48
Net periodic benefit cost	$	732		$	782

The Company did not make any contributions to the qualified pension benefit plan for the three months ended March 31, 2017 and 2016.