Employee Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2012

Employee Benefit Plans [Abstract]

Schedule of Net Periodic Benefit Costs of Pension and Post-Retirement Healthcare

	Three Months Ended June 30, 2012						Three Months Ended June 30, 2011
	Qualified Pension			Post- retirement Healthcare			Qualified Pension			Post- retirement Healthcare
Service cost	$	4,096		$	6,784		$	3,177		$	4,310
Interest cost		3,637			6,183			3,655			4,813
Expected return on plan assets		(3,252	)		(9	)		(3,634	)		(3	)
Amortization of actuarial loss		525			1,682			—			—
Net periodic benefit cost	$	5,006		$	14,640		$	3,198		$	9,120

													Predecessor Company
	Six Months Ended June 30, 2012						One Hundred Fifty-Seven Days Ended June 30, 2011						Twenty-Four Days Ended January 24, 2011
	Qualified Pension			Post- retirement Healthcare			Qualified Pension			Post- retirement Healthcare			Qualified Pension			Post- retirement Healthcare
Service cost	$	8,192		$	13,568		$	5,295		$	7,183		$	849		$	1,167
Interest cost		7,299			12,365			6,092			8,022			934			1,252
Expected return on plan assets		(6,531	)		(17	)		(6,056	)		(5	)		(1,089	)		(1	)
Amortization of prior service cost		—			—			—			—			98			276
Amortization of actuarial loss		1,042			3,364			—			—			283			368
Plan settlement		356			—			—			—			—			—
Net periodic benefit cost	$	10,358		$	29,280		$	5,331		$	15,200		$	1,075		$	3,062