Discontinued Operations - Financial Results (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net (loss) income from discontinued operations	$ (241,699)	$ 47,387	$ (222,458)	$ 75,443
Sightline Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) income from discontinued operations, before income taxes				(7,500)
Digital
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating revenues	272,746	334,807	592,147	659,280
Cost of revenue and SG&A expenses	206,350	234,737	461,984	480,556
Depreciation	9,700	8,149	19,570	15,531
Amortization	16,670	22,476	40,300	44,773
Asset impairment and facility consolidation charges	344,772	0	344,772	0
Total operating expenses	577,492	265,362	866,626	540,860
Total operating (loss) income	(304,746)	69,445	(274,479)	118,420
Non-operating income (expense)	211	(1,490)	(1,726)	(5,685)
(Loss) income from discontinued operations, before income taxes	(304,535)	67,955	(276,205)	112,735
Provision for income taxes	62,836	(20,568)	53,747	(37,292)
Net (loss) income from discontinued operations	$ (241,699)	$ 47,387	$ (222,458)	$ 75,443