Pension and Other Postretirement Benefits (Tables)

3 Months Ended

Mar. 31, 2015

Compensation and Retirement Disclosure [Abstract]

Components of net periodic benefit cost

The components of net periodic benefit cost are as follows (in thousands):

	Pension Benefits						Other Postretirement Benefits
	For the three months ended   March 31,						For the three months ended   March 31,
	2015			2014			2015			2014
Components of net periodic benefit cost:
Service cost	$	2,178		$	1,701		$	1,875		$	1,944
Interest cost	3,297			3,348			6,351			7,726
Expected return on plan assets	(3,696		)	(4,553		)	—			—
Amortization of prior service cost (credit)	169			61			(1,552		)	307
Amortization of net actuarial loss	1,865			642			5,659			3,892
Settlement loss	—			784			—			—
Net periodic benefit cost	$	3,813		$	1,983		$	12,333		$	13,869