Other Long-Term Assets (Schedule of Other Long-Term Assets) (Details) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Long-term assets:
Advance coal royalties		$ 6,506	$ 5,496
Deferred financing costs, net		5,461	6,507
Marketable equity securities available for sale, at fair value (restricted)	[1]	1,723	2,249
Other		2,782	4,597
Long-term assets		$ 16,472	$ 18,849

[1] Held by Sunrise Indemnity, Inc., our wholly owned captive insurance company.