Retirement Benefits

3 Months Ended

Mar. 31, 2015

Retirement Benefits [Abstract]

Retirement Benefits

14.       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)	2015			2014
Service cost	$	2,940		$	2,460
Interest cost		2,457			2,542
Expected return on plan assets		(2,903	)		(2,823	)
Amortization of prior service cost		5			13
Amortization of net (income) loss		2,251			1,091
Net periodic benefit cost	$	4,750		$	3,283

Other Benefits	Three Months Ended
	March 31,
(Dollars in thousands)	2015		2014
Service cost	$	401	$	407
Interest cost		263		342
Amortization of net (income) loss		211		82
Net periodic benefit cost	$	875	$	831

The Company did not make any contributions to the qualified pension benefit plan for the three months ended March 31, 2015 and 2014.