Debt - Summary of Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 10, 2015	Dec. 31, 2014	Jun. 05, 2013
Debt Disclosure [Abstract]
Cash Convertible Senior Subordinated Notes, Carrying Amount	$ 0		$ 117,259
8.25% Senior Secured Notes, Carrying Amount	0		305,000
6.875% Senior Secured Notes, Carrying Amount	495,113		0
Total Debt, Carrying Amount	495,113		422,259
Cash Convertible Senior Subordinated Notes, Fair Value	0		116,819
8.25% Senior Secured Notes, Fair Value	0		309,194
6.875% Senior Secured Notes, Fair Value	480,259		0
Total Debt, Fair Value	$ 480,259		$ 426,013
Senior Secured Notes [Member] | 8.25% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Interest rate	8.25%		8.25%	8.25%
Senior Secured Notes [Member] | 6.875% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Interest rate	6.875%	6.875%