16.Benefit Plans

Pension Plans

All benefits under the primary Company-sponsored pension plan were frozen in 2006 and no benefits have accrued to participants after this date. The Company also sponsors a pension plan for certain employees under collective bargaining agreements. Benefits under the pension plan for collectively bargained employees are determined in accordance with negotiated formulas for the respective participants. Contributions to the plans are based on actuarial determined amounts and are limited to the amounts currently deductible for income tax purposes.

The components of net periodic pension cost were as follows:

	Third Quarter						First Three Quarters
(in thousands)	2016			2015			2016			2015
Service cost	$	28		$	35		$	85		$	105
Interest cost		3,031			2,974			9,093			8,921
Expected return on plan assets		(3,458	)		(3,388	)		(10,373	)		(10,162	)
Recognized net actuarial loss		741			795			2,222			2,386
Amortization of prior service cost		7			9			21			27
Net periodic pension cost	$	349		$	425		$	1,048		$	1,277

The Company contributed $11.1 million to the Company-sponsored pension plans during the first three quarters of 2016. The Company may make additional contributions to the two Company-sponsored pension plans of up to $1.0 million during the fourth quarter of 2016.

Postretirement Benefits

The Company provides postretirement benefits for a portion of its current employees. The Company recognizes the cost of postretirement benefits, which consist principally of medical benefits, during employees’ periods of active service. The Company does not pre-fund these benefits and has the right to modify or terminate certain of these benefits in the future.

The components of net periodic postretirement benefit cost were as follows:

	Third Quarter						First Three Quarters
(in thousands)	2016			2015			2016			2015
Service cost	$	350		$	325		$	1,050		$	975
Interest cost		778			708			2,333			2,123
Recognized net actuarial loss		587			717			1,762			2,152
Amortization of prior service cost		(840	)		(840	)		(2,520	)		(2,520	)
Net periodic postretirement benefit cost	$	875		$	910		$	2,625		$	2,730

Multi-Employer Benefits

Certain employees of the Company participate in a multi-employer pension plan, the Employers-Teamsters Local Union Nos. 175 and 505 Pension Fund (the “Plan”), to which the Company makes monthly contributions on behalf of such employees. The Plan was certified by the Plan’s actuary as being in “critical” status for the plan year beginning January 1, 2013. As a result, the Plan adopted a “Rehabilitation Plan” effective January 1, 2015. The Company agreed and incorporated such agreement in the renewal of the collective bargaining agreement with the union, effective April 28, 2014, to participate in the Rehabilitation Plan. The Company increased its contribution rates to the Plan effective January 2015 with additional increases occurring annually to support the Rehabilitation Plan.

There would likely be a withdrawal liability in the event the Company withdraws from its participation in the Plan. The Company’s withdrawal liability was reported by the Plan’s actuary to be approximately $4.5 million. The Company does not currently anticipate withdrawing from the Plan.