Benefit Plans and Other Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2014

Benefit Plans and Other Postretirement Benefits

Schedule of components of net pension expense

	Pension Benefits						Other Postretirement Benefits
	Three months ended September 30,
	2014			2013			2014		2013
Service cost	$	2,036		$	2,103		$	28	$	40
Interest cost	6,005			5,117			123		127
Expected return on plan assets	(7,117		)	(6,071		)	—		—
Amortization of transition obligation	(25		)	(27		)	—		—
Amortization of prior service cost	673			485			—		—
Amortization of net actuarial losses	4,010			5,901			104		193
Net pension expense	$	5,582		$	7,508		$	255	$	360

	Pension Benefits						Other Postretirement Benefits
	Nine months ended September 30,
	2014			2013			2014		2013
Service cost	$	6,131		$	6,318		$	83	$	120
Interest cost	18,057			15,431			368		382
Expected return on plan assets	(21,372		)	(18,346		)	—		—
Amortization of transition obligation	(74		)	(81		)	—		—
Amortization of prior service cost	2,019			1,465			—		—
Amortization of net actuarial losses	12,045			17,703			314		578
Net pension expense	$	16,806		$	22,490		$	765	$	1,080