Benefit Plans

The components of our consolidated net pension costs are set forth in the following table:



	For the Three Months Ended						For the Six Months Ended
	June 30,						June 30,
	2014			2015			2014			2015
	(Dollars in thousands)						(Dollars in thousands)
Service cost	$	473		$	506		$	946		$	1,333
Interest cost	2,169			1,526			4,338			3,052
Expected return on plan assets	(1,938		)	(1,354		)	(3,876		)	(2,708		)
Amortization of prior service cost	1			1			2			2
Net cost	$	705		$	679		$	1,410		$	1,679

The components of our consolidated net postretirement costs are set forth in the following table:



	For the Three Months Ended						For the Six Months Ended
	June 30,						June 30,
	2014			2015			2014			2015
	(Dollars in thousands)						(Dollars in thousands)
Service cost	$	19		$	4		$	38		$	8
Interest cost	352			315			704			630
Curtailment loss	1,048			—			1,048			—
Amortization of prior service benefit	(47		)	(43		)	(94		)	(86		)
Net cost	$	1,372		$	276		$	1,696		$	552

On March 27, 2015, we settled $59.0 million of projected benefit obligations in the United Kingdom through the purchase of a group annuity contract. The purchase was fully funded with pension assets. The obligation associated with this transaction will require no additional cash contributions by the company. The results of this settlement were not material to our operations.