Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Revenues	$ 206,557	$ 214,098	$ 413,373	$ 428,072
Operating expenses:
Cost of services and sales, excluding depreciation and amortization	93,302	97,968	198,341	232,349
Other post-employment benefit and pension expense	(53,486)	(52,460)	(106,714)	(59,358)
Selling, general and administrative expense, excluding depreciation and amortization	49,440	53,434	99,776	109,280
Depreciation and amortization	55,105	55,818	112,743	111,124
Reorganization related expense	0	20	0	27
Total operating expenses	144,361	154,780	304,146	393,422
Income from operations	62,196	59,318	109,227	34,650
Interest expense	(20,583)	(19,974)	(41,193)	(39,793)
Other, net	95	97	253	272
Total other expense	(20,488)	(19,877)	(40,940)	(39,521)
Income/(loss) before income taxes	41,708	39,441	68,287	(4,871)
Income tax (expense)/benefit	(12,393)	824	(20,404)	(77)
Net income/(loss)	$ 29,315	$ 40,265	$ 47,883	$ (4,948)
Weighted average shares outstanding:
Basic, in shares	26,858,029	26,654,518	26,834,863	26,621,662
Diluted, in shares	27,083,512	27,025,361	27,070,678	26,621,662
Income/(loss) per share, basic (in dollars per share)	$ 1.09	$ 1.51	$ 1.78	$ (0.19)
Income/(loss) per share, diluted (in dollars per share)	$ 1.08	$ 1.49	$ 1.77	$ (0.19)