Long-term Debt - Narrative (Details) - USD ($)		3 Months Ended		9 Months Ended
	Apr. 12, 2011	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Apr. 15, 2014
Debt Instrument [Line Items]
Private placement date	Apr. 12, 2011
Issuance of private placement, principal amount	$ 200,000,000.0
Interest rate	8.75%	8.75%		8.75%
Term of payments of interest on notes	semi-annually
Total amount of debt to be retired						$ 50,000,000
Percentage of debt to be retired from the total debt						25.00%
Proceeds from sale of assets, limit				$ 15,000,000
Interest expense on note		$ 3,300,000	$ 3,300,000	$ 9,800,000	$ 9,800,000