Consolidated and Combined Statement of Equity Prior Year - USD ($) $ in Thousands	Total	Parent Company Equity [Member]	AOCI Attributable to Parent [Member]	Noncontrolling Interest [Member]
Beginning balance at Dec. 31, 2012	$ 195,781	$ 209,931	$ (16,934)	$ 2,784
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(16,829)	(16,703)		(126)
Changes in defined benefit pension plans	3,589		3,589
Transfers to Parent, net	5,153	5,153
Other	150		150
Ending balance at Dec. 31, 2013	187,844	198,381	(13,195)	2,658
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(25,970)	(25,766)		(204)
Changes in defined benefit pension plans	(13,474)		(13,474)
Transfer of Knoxville and Memphis defined benefit pension plans (Note 14)	17,622	(6,505)	24,127
Transfers to Parent, net	3,465	3,465
Other	(240)		(240)
Ending balance at Dec. 31, 2014	169,247	169,575	(2,782)	2,454
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	3,029
Changes in defined benefit pension plans	886
Transfers to Parent, net	(7,262)	$ (7,262)
Ending balance at Dec. 31, 2015	$ 249,699		$ (2,587)	$ 2,356