Retirement Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2015

Compensation and Retirement Disclosure [Abstract]

Schedule of Net Benefit Cost

The following tables present the components of net periodic benefit cost (gains are denoted with parentheses and losses are not):

	Three Months Ended March 31, 2015
(in thousands)	Hourly Employees’ Pension Plan				Employees’ Retirement Plan				Total
Service cost		$	2			$	1		$	3
Interest cost		101				217			318
Expected return on plan assets		(165		)		(307		)	(472		)
Amortization of prior service cost		—				—			—
Amortization of net (gain)/loss		62				100			162
Net periodic benefit cost		$	—			$	11		$	11

	Three Months Ended March 31, 2014
(in thousands)	Hourly Employees’ Pension Plan				Employees’ Retirement Plan				Total
Service cost		$	2			$	1		$	3
Interest cost		105				213			318
Expected return on plan assets		(159		)		(295		)	(454		)
Amortization of prior service cost		—				—			—
Amortization of net (gain)/loss		18				15			33
Net periodic benefit cost		$	(34	)		$	(66	)	$	(100	)