Other Long-Term Assets and Other Income (Schedule of Other Long-Term Assets) (Details) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014
Long-term assets:
Advance coal royalties		$ 6,563	$ 5,496
Deferred financing costs, net		5,112	6,507
Marketable equity securities available for sale, at fair value (restricted)	[1]	1,763	2,249
Other		3,090	4,597
Other noncurrent assets total		$ 16,528	$ 18,849

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