Pension and Other Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2012

Pension and Other Postretirement Benefits [Abstract]

Schedule of Net Benefit Costs [Table Text Block]

	Pension Benefits						Postretirement Benefits
	Three Months Ended June 30,						Three Months Ended June 30,
Components of Net Periodic Benefit Cost	2012			2011			2012			2011
Service cost	$	5,532		$	4,099		$	518		$	496
Interest cost	6,123			5,642			828			914
Expected return on plan assets	(5,910		)	(5,492		)	—			—
Amortization of:
Net actuarial loss	5,408			3,527			435			460
Prior service cost (gain)	340			377			(565		)	(565		)
Net periodic benefit cost	$	11,493		$	8,153		$	1,216		$	1,305
	Pension Benefits						Postretirement Benefits
	Six Months Ended June 30,						Six Months Ended June 30,
Components of Net Periodic Benefit Cost	2012			2011			2012			2011
Service cost	$	11,107		$	8,249		$	1,168		$	1,071
Interest cost	12,448			11,342			1,678			1,839
Expected return on plan assets	(11,835		)	(10,942		)	—			—
Amortization of:
Net actuarial loss	10,558			7,052			860			985
Prior service cost (gain)	690			702			(1,090		)	(1,090		)
Net periodic benefit cost	$	22,968		$	16,403		$	2,616		$	2,805