Income Taxes - Additional Information (Details) (USD $)	3 Months Ended														11 Months Ended	12 Months Ended	3 Months Ended		11 Months Ended	12 Months Ended				11 Months Ended	12 Months Ended		1 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Sep. 30, 2010	Jun. 30, 2010	Dec. 31, 2010	Dec. 31, 2011	Sep. 30, 2011 Successor Company	Jun. 30, 2011 Successor Company	Dec. 31, 2010 Successor Company	Dec. 31, 2012 Successor Company	Dec. 31, 2011 Successor Company	Dec. 31, 2012 Successor Company Federal	Dec. 31, 2012 Successor Company State and Local Jurisdiction	Dec. 31, 2010 Successor Company Changes in Liabilities for Uncertain Tax Positions	Dec. 31, 2011 Successor Company Changes in Liabilities for Uncertain Tax Positions	Dec. 31, 2011 Successor Company Changes in Liabilities for Uncertain Tax Positions Related to IRC Section 108 Planning and Non Business Income Audit in State of Illinois	Jan. 31, 2010 Predecessor Company
Income Tax [Line Items]
(Provision) benefit for income taxes	$ (10,025,000)	$ 6,641,000	$ (4,707,000)	$ 1,167,000	$ (17,992,000)		$ (719,000)		$ 163,714,000		$ (20,245,000)								$ 620,115,000	$ (6,924,000)	$ 124,758,000						$ (917,541,000)
Federal income tax benefit (provision)																			567,675,000	1,361,000	92,936,000						(792,762,000)
State and local income tax benefit (provision)																			52,440,000	(8,285,000)	31,822,000						(124,779,000)
Current federal tax benefit (provision)																			(1,263,000)	4,689,000	18,955,000						(600,000)
Deferred federal income tax benefit (provision)																			568,938,000	(3,328,000)	73,981,000						(792,162,000)
Current state and local tax benefit (provision)																			3,772,000	(4,535,000)	(2,905,000)						(20,000)
Deferred state and local income tax benefit (provision)																			48,668,000	(3,750,000)	34,727,000						(124,759,000)
Debt repurchase tax gain																				141,500,000
Estimated increase (decrease) in deferred tax assets																			328,700,000	(54,600,000)
Change in income tax (provision) benefit																			299,900,000		177,200,000			(352,300,000)	(24,000,000)	5,100,000
Income tax expense, change in valuation allowance																				38,900,000	(51,200,000)
Decrease effective income tax rate, change in valuation allowance																			(2.30%)	(56.20%)	(8.00%)						(19.50%)
Increase effective income tax rate, non-deductible interest expense																			0.00%	8.10%	0.00%						0.00%
Income tax benefit, section 1245 recapture																				10,000,000	(81,100,000)
Increase effective income tax rate, section 1245 recapture																			0.00%	14.50%	12.60%						0.00%
Income Tax Provision, non-deductible interest expense																				(5,600,000)
Fresh Start Accounting, Debt Discharge Tax Gain																			5,016,600,000
Effective income tax rate adjusted for changes in tax items																									3.70%	(0.80%)
Non-deductible impairment expenses, decrease in effective tax rate																			(19.50%)	0.00%	(27.50%)						0.00%
Impairment charges					0	[1]	0	[1]	801,074,000	[1]	0	[1]	385,283,000	752,340,000	1,137,623,000	801,074,000		801,074,000
Nondeductible expense, impairment losses																		457,200,000
Effective tax rate																			40.20%	10.00%	19.40%						11.70%
Statutory federal tax rate																			35.00%	35.00%	35.00%						35.00%
Deferred tax assets, gross	500,229,000				577,994,000											577,994,000				500,229,000	577,994,000
Deferred tax liabilites, gross	391,219,000				428,522,000											428,522,000				391,219,000	428,522,000
Deferred tax asset, net operating loss and credit carryforwards	434,106,000				500,481,000											500,481,000				434,106,000	500,481,000
Valuation allowance	123,786,000				157,171,000											157,171,000				123,786,000	157,171,000
Increase (decrease) in unrecognized tax benefits																	1,800,000		(370,600,000)							5,200,000
Unrecognized tax benefits that would impact effective tax rate																				5,700,000	5,700,000						377,000,000
Unrecognized Tax Benefits, Reversing																				700,000
Interest and penalties due to unrecognized tax benefits																			500,000		(4,800,000)						400,000
Unrecognized tax benefits, income tax interest accrued																					0						8,300,000
Gross reductions for tax positions related to the lapse of applicable statute of limitations																			0	0	20,261,000				28,200,000		0
Operating Loss Carryforwards																						985,300,000	1,975,400,000
Percentage of common stock purchase by one person or group of persons prohibited																				4.90%
Decrease in deferred tax liabilities and goodwill																			$ 158,400,000

[1] We recognized a goodwill impairment charge of $801.1 million during the three months ended June 30, 2011. See Note 2, “Summary of Significant Accounting Policies – Identifiable Intangible Assets and Goodwill” for further discussion.