Debt - Summary of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Mar. 10, 2015	Dec. 31, 2014	Jun. 05, 2013
Carrying Amount
Cash Convertible Senior Subordinated Notes	$ 0		$ 117,259
8.25% Senior Secured Notes	0		305,000
6.875% Senior Secured Notes	495,632		0
Total Debt	495,632		422,259
Fair Value
Cash Convertible Senior Subordinated Notes	0		116,819
8.25% Senior Secured Notes	0		309,194
6.875% Senior Secured Notes	450,000		0
Total Debt	$ 450,000		$ 426,013
Senior Secured Notes | 6.875% Senior Secured Notes
Debt Instrument [Line Items]
Interest rate	6.875%	6.875%
Senior Secured Notes | 8.25% Senior Secured Notes
Debt Instrument [Line Items]
Interest rate	8.25%			8.25%