Debt - Term Loan Facility (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jul. 15, 2015
Debt
Face amount of debt	$ 2,726.0	$ 2,726.0		$ 2,726.0
Term Loan Facility
Debt
Face amount of debt	$ 700.0	700.0		$ 700.0
Period prior to debt maturity				91 days
Weighted average interest rate (as a percent)	1.52%		8.75%	7.10%	8.75%
Interest expense		$ 0.0
Term Loan Facility | Liabilities Subject to Compromise
Debt
Accrued interest						$ 30.2
Incremental Term Loan | Variable Rate Base Adjusted Eurodollar
Debt
Variable interest margin (as a percent)				7.50%
Interest rate floor				1.25%
Incremental Term Loan | Alternate Base Rate
Debt
Variable interest margin (as a percent)				6.50%
Interest rate floor				2.25%