Taxes on Income 1 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012 Successor [Member]	Jun. 30, 2012 Successor [Member]	Mar. 25, 2012 Predecessor [Member]	Jun. 30, 2011 Predecessor [Member]	Jun. 30, 2011 Predecessor [Member]
Current:
Federal	$ 0	$ 0	$ 0	$ 136	$ 173
State	482	482	5	716	(7,486)
Total current	482	482	5	852	(7,313)
Deferred:
Federal	9,007	(1,814)	19,861	24,419	48,604
State	1,369	256	3,005	317	2,939
Total deferred	10,376	(1,558)	22,866	24,736	51,543
Total federal and state income tax expense (benefit)	$ 10,858	$ (1,076)	$ 22,871	$ 25,588	$ 44,230
Effective tax rate	48.00%	4.00%	31.00%	30.00%	27.00%

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