Pension and Other Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2013

Compensation and Retirement Disclosure [Abstract]

Schedule of Net Benefit Costs

Pension and other postretirement benefits expenses consisted of the following:

	Three months ended June 30,						Six months ended June 30,
Pensions	2013			2012			2013			2012
Service cost	$	1,462		$	1,645		$	3,446		$	3,258
Interest cost	5,038			5,415			10,025			10,737
Expected return on plan assets	(8,318		)	(8,257		)	(16,594		)	(16,290		)
Amortization of prior service cost	179			209			382			420
Recognized losses	4,218			3,100			8,293			5,859
Curtailment loss	—			—			199			—
Settlement loss	637			—			637			—
Special termination benefits	1,016			—			1,016			—
Net periodic benefit cost	$	4,232		$	2,112		$	7,404		$	3,984
	Three months ended June 30,						Six months ended June 30,
Other Postretirement Benefits	2013			2012			2013			2012
Service cost	$	41		$	59		$	118		$	136
Interest cost	492			579			1,035			1,259
Amortization of prior service credit	(165		)	(397		)	(560		)	(793		)
Recognized losses	231			256			521			542
Curtailment gain	(3,081		)	—			(3,081		)	—
Net periodic benefit cost	$	(2,482	)	$	497		$	(1,967	)	$	1,144