Segment Information - EBITDA Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Information
Net income (loss) attributable to controlling interests and available to common shareholders	$ 8,781	$ (175,561)	$ 9,780	$ (161,304)
Interest expense, net	8,852	9,743	27,185	25,760
Amortization of deferred financing costs and note discount	3,397	3,195	10,060	9,317
Income tax expense (benefit)	7,854	(4,053)	10,409	(2,335)
Depreciation and accretion expense	30,647	29,807	93,453	88,683
Amortization of intangible assets	12,994	14,996	40,263	45,423
EBITDA	72,525	(121,873)	191,150	5,544
Loss on disposal and impairment of assets	466	22,307	15,583	26,170
Other income	(1,297)	(2,095)	(1,324)	(1,730)
Noncontrolling interests	12	(9)	31	(19)
Share-based compensation expense	4,669	4,151	10,627	9,971
Restructuring expenses add-back	1,058	22	5,534	9,025
Acquisition and divestiture-related expenses		2,889	2,633	15,338
Goodwill and intangible asset impairment		194,521		194,521
Adjusted EBITDA	77,433	99,913	224,234	258,820
Depreciation and accretion expense adjustment	30,646	29,805	93,451	88,677
Adjusted EBITA	$ 46,787	$ 70,108	$ 130,783	$ 170,143