Voluntary Reorganization Under Chapter 11 (Narrative) (Details) (USD $)	0 Months Ended		12 Months Ended
	Oct. 10, 2014	Sep. 02, 2014	Dec. 31, 2014	Oct. 31, 2012	Feb. 29, 2012	Dec. 31, 2013	Jul. 31, 2011
Debt Instrument [Line Items]
Interest due		$ 33,500,000
Grace period			30 days
Proposed (decrease) in existing debt	(568,000,000)
First Priority Notes [Member]
Debt Instrument [Line Items]
Interest rate		12.00%			12.00%
Proposed debt issuance amount	262,500,000			54,000,000	350,000,000
Second Priority Notes [Member]
Debt Instrument [Line Items]
Interest rate		12.00%
Proposed debt issuance amount					150,000,000
6.5% Convertible Notes [Member]
Debt Instrument [Line Items]
Interest rate		6.50%
7.5% Fixed Rate [Member]
Debt Instrument [Line Items]
Interest rate	7.50%		7.50%			7.50%
Convertible Senior Notes, 5.5% Fixed Rate, Due 2016 [Member]
Debt Instrument [Line Items]
Interest rate	5.50%		5.50%			5.50%	5.50%
Proposed debt issuance amount							135,000,000
First And Second Priority Notes [Member]
Debt Instrument [Line Items]
Proposed debt issuance amount	$ 237,500,000