Summary of Significant Accounting Policies - Schedule of Earnings Per Share, Basic and Diluted (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 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	Dec. 31, 2010 Successor Company	Dec. 31, 2012 Successor Company	Dec. 31, 2011 Successor Company	Jan. 31, 2010 Predecessor Company
Basic EPS
Net income (loss)	$ (35,446)	$ (12,665)	$ 52,940	$ 57,572	$ 5,549	$ 22,184	$ (602,107)	$ 55,410	$ (923,592)	$ 62,401	$ (518,964)	$ 6,920,009
Weighted average common shares outstanding									50,020	50,643	50,144	69,013
Basic earnings (loss) per share (in dollars per share)	$ (0.70)	$ (0.25)	$ 1.05	$ 1.15	$ 0.11	$ 0.44	$ (12.01)	$ 1.11	$ (18.46)	$ 1.23	$ (10.35)	$ 100.27
Diluted EPS
Net income (loss)	$ (35,446)	$ (12,665)	$ 52,940	$ 57,572	$ 5,549	$ 22,184	$ (602,107)	$ 55,410	$ (923,592)	$ 62,401	$ (518,964)	$ 6,920,009
Weighted average common shares outstanding									50,020	50,643	50,144	69,013
Dilutive effect of stock awards									0	10	0	39
Weighted average diluted shares outstanding									50,020	50,653	50,144	69,052
Diluted earnings (loss) per share (in dollars per share)	$ (0.70)	$ (0.25)	$ 1.05	$ 1.15	$ 0.11	$ 0.44	$ (12.01)	$ 1.11	$ (18.46)	$ 1.23	$ (10.35)	$ 100.21