Employee Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2013

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

Schedule of Net Benefit Costs [Table Text Block]

The net pension and postretirement benefit costs that have been recognized during the stated periods are shown in the following tables:

	Pension						Postretirement
	Three Months Ended March 31,						Three Months Ended March 31,
	2013			2012			2013		2012
Components of Net Periodic Benefit Cost
Service cost	$	2,419		$	1,940		$	249	$	210
Interest cost	4,834			3,989			240		223
Expected return on plan assets	(7,424		)	(5,879		)	—		—
Amortization of prior service cost	388			302			6		6
Amortization of losses	5,727			4,056			218		144
Net periodic benefit cost	$	5,944		$	4,408		$	713	$	583