Earnings (Losses) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jan. 31, 2017
Net income (loss) (numerator):
Income (loss) from continuing operations, net of tax	$ (195,215)	$ (115,476)	$ (338,802)	$ (263,104)
Less: net (income) loss attributable to noncontrolling interest	(2,953)	(1,971)	(3,492)	(2,888)
Less: preferred stock dividends	(3,680)		(3,680)
Less: accrued distribution on redeemable noncontrolling interest in subsidiary	(2,124)		(4,522)
Less: (earnings) losses allocated to unvested shareholders	4,826	3,306	8,186	7,117
Adjusted income (loss) from continuing operations, net of tax - basic	(199,146)	(114,141)	(342,310)	(258,875)
Income (loss) from discontinued operations, net of tax	$ (584)	$ (15,504)	$ (659)	$ (15,943)
Weighted-average number of shares outstanding - basic	328,372	278,916	318,580	278,348
Earnings (losses) Per Share - Basic
Basic from continuing operations (in dollars per share)	$ (0.61)	$ (0.41)	$ (1.08)	$ (0.93)
Basic from discontinued operations (in dollars per share)		(0.05)		(0.06)
Total Basic (in dollars per share)	$ (0.61)	$ (0.46)	$ (1.08)	$ (0.99)
DILUTED EPS:
Adjusted income (loss) from continuing operations, net of tax - basic	$ (199,146)	$ (114,141)	$ (342,310)	$ (258,875)
Adjusted income (loss) from continuing operations, net of tax - diluted	(199,146)	(114,141)	(342,310)	(258,875)
Income (loss) from discontinued operations, net of tax	$ (584)	$ (15,504)	$ (659)	$ (15,943)
Weighted-average number of shares outstanding - basic	328,372	278,916	318,580	278,348
Weighted-average number of shares outstanding - diluted	328,372	278,916	318,580	278,348
Earnings (losses) per share:
Diluted from continuing operations (in dollars per share)	$ (0.61)	$ (0.41)	$ (1.08)	$ (0.93)
Diluted from discontinued operations (in dollars per share)		(0.05)		(0.06)
Total Diluted (in dollars per share)	$ (0.61)	$ (0.46)	$ (1.08)	$ (0.99)
0.75% senior exchangeable notes due January 2024
Earnings (losses) per share:
Aggregate amount of senior notes	$ 575,000		$ 575,000		$ 575,000
Interest rate on senior notes due (as a percent)	0.75%		0.75%
0.75% senior exchangeable notes due January 2024 | Minimum
Earnings (losses) per share:
Share issued price (in dollars per share)	$ 25.16		$ 25.16