Pension and Other Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2014

Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]

Schedule of Net Benefit Costs

The net periodic benefit cost for the three and nine months ended September 30, 2014 and 2013 included the following components: 

	Pension Benefits						Postretirement Benefits
	Three Months Ended   September 30,						Three Months Ended   September 30,
Components of Net Periodic Benefit Cost	2014			2013			2014			2013
Service cost	$	5,551		$	6,030		$	614		$	661
Interest cost	6,704			5,979			834			718
Expected return on plan assets	(6,656		)	(5,977		)	—			—
Amortization of:
Net actuarial loss	4,410			6,593			317			449
Prior service cost (gain)	238			343			(545		)	(545		)
Net periodic benefit cost	$	10,247		$	12,968		$	1,220		$	1,283
	Pension Benefits						Postretirement Benefits
	Nine Months Ended   September 30,						Nine Months Ended   September 30,
Components of Net Periodic Benefit Cost	2014			2013			2014			2013
Service cost	$	16,654		$	18,089		$	1,841		$	1,983
Interest cost	20,113			17,936			2,502			2,154
Expected return on plan assets	(19,968		)	(17,931		)	—			—
Amortization of:
Net actuarial loss	13,229			19,778			951			1,346
Prior service cost (gain)	714			1,031			(1,635		)	(1,635		)
Settlement loss	789			—			—			—
Net periodic benefit cost	$	31,531		$	38,903		$	3,659		$	3,848