Summarized Quarterly Financial Information (Unaudited) - Schedule (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended										12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Selected Quarterly Financial Information [Abstract]
Operating revenues	$ 204,808			$ 150,626	$ 189,691	$ 198,134	$ 123,023	$ 123,126	$ 119,696	$ 105,304	$ 715,656	$ 498,752	$ 432,357
Costs and expenses	(223,095)			(115,759)	(173,962)	(200,209)	(124,214)	(111,721)	(114,394)	(102,037)	(721,480)	(443,911)	(401,744)
Depreciation and amortization of intangibles	(14,018)			(8,549)	(16,273)	(13,366)	(8,295)	(8,706)	(7,438)	(7,487)	(51,952)	(32,180)	(30,522)
Asset impairment charges		$ (24,613)									(24,613)	0	0
(Losses) gains, net on disposal of property, plant and equipment	96			(59)	(200)	(215)	(164)	2,979	(13)	(35)	(483)	2,872	(296)
Interest expense	(4,576)			(2,149)	(4,246)	(4,225)	(2,052)	(2,050)	(2,041)	(2,254)	(15,099)	(8,494)	(10,437)
Miscellaneous, net	(1,433)			(7,483)	1,061	387	(1,436)	170	(237)	(143)	(1,421)	(7,693)	(11,350)
Income (loss) before income taxes	(38,218)		$ (13,138)	16,627	(28,542)	(19,494)		3,798	(4,427)	(6,652)	(99,392)	9,346	(21,992)
Benefit (provision) for income taxes	(17,094)			1,197	(4,099)	(6,539)	(5,023)	2,755	(1,591)	(2,472)	(32,755)	(111)	(11,907)
Net (loss) income from continuing operations	(21,124)			15,430	(24,443)	(12,955)	(8,115)	1,043	(2,836)	(4,180)	(66,637)	9,457
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(407)			287	0	(18,448)	3,015	(2,384)	(399)	3,568	(15,840)	1,072	9,611
Net (loss) income	$ (21,531)			$ 15,717	$ (24,443)	$ (31,403)	$ (5,100)	$ (1,341)	$ (3,235)	$ (612)	$ (82,477)	$ 10,529	$ (474)
Income (Loss) from Continuing Operations, Per Basic Share	$ (0.25)			$ 0.26	$ (0.29)	$ (0.15)	$ (0.14)	$ 0.02	$ (0.05)	$ (0.07)	$ (0.86)	$ 0.16	$ (0.18)
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share	$ 0.00			0.01	$ 0.00	$ (0.22)	$ 0.05	(0.04)	(0.01)	0.06	(0.20)	0.02	0.17
Income (Loss) from Continuing Operations, Per Diluted Share				0.26				0.02	(0.05)	(0.07)	(0.86)	0.16	(0.18)
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share				$ 0.01				$ (0.04)	$ (0.01)	$ 0.06	$ (0.20)	$ 0.02	$ 0.17
Basic weighted-average shares outstanding	83,775			56,763	84,107	83,903	57,335	56,469	56,043	56,084	77,373	56,342	56,516
Diluted weighted-average shares outstanding	83,775			57,474	84,107	83,903	57,335	56,469	56,043	56,084	77,373	57,239	56,516
Cash dividends per share of common stock (USD per share)	$ 0.00			$ 0	$ 0.00	$ 1.03	$ 0.00	$ 0	$ 0	$ 0	$ 1.03	$ 0	$ 0