Retirement and Benefit Plans

The following table presents the pension benefit costs:



	Three Months Ended March 31
	2018			2017
	(thousands)
Service cost	$	205		$	301
Interest cost	4,011			4,376
Expected return on plan assets	(4,588		)	(4,740		)
Amortization of actuarial loss	821			395
Net periodic benefit expense	$	449		$	332

Service cost is recorded in the same income statement line items as other employee compensation costs arising from services rendered, and the other components of net periodic benefit expense are recorded in "Pension expense (excluding service costs) in our Consolidated Statements of Operations.

During the three months ended March 31, 2018, we contributed $0.5 million in cash to the pension plans. For the remainder of 2018, we expect to make approximately $1.6 million in cash contributions to the pension plans. Also, we may make additional discretionary pension contributions in 2018.

On April 25, 2018, Boise Cascade transferred $151.8 million of its pension plan assets to The Prudential Insurance Company of America (Prudential) for the purchase of a group annuity contract. Under the arrangement, Prudential will assume ongoing responsibility for administration and benefit payments for approximately one-third of Boise Cascade’s U.S. qualified pension plan projected benefit obligations. As a result of the transaction, the Company expects to recognize a non-cash pension settlement charge of approximately $12 million before tax in the second quarter of 2018.