Earnings (Losses) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Jan. 31, 2017
Net income (loss) (numerator):
Income (loss) from continuing operations, net of tax	$ (147,628)	$ (396,644)
Less: net (income) loss attributable to noncontrolling interest	(917)	(724)
Less: (earnings) losses allocated to unvested shareholders	3,811	8,199
Adjusted income (loss) from continuing operations, net of tax - basic	(144,734)	(389,169)
Income (loss) from discontinued operations, net of tax	$ (439)	$ (926)
Weighted-average number of shares outstanding - basic	277,781	275,851
Earnings (losses) Per Share - Basic
Basic from continuing operations (in dollars per share)	$ (0.52)	$ (1.41)
Total Basic (in dollars per share)	$ (0.52)	$ (1.41)
DILUTED EPS:
Adjusted income (loss) from continuing operations, net of tax - basic	$ (144,734)	$ (389,169)
Adjusted income (loss) from continuing operations, net of tax - diluted	(144,734)	(389,169)
Income (loss) from discontinued operations, net of tax	$ (439)	$ (926)
Weighted-average number of shares outstanding - basic	277,781	275,851
Weighted-average number of shares outstanding - diluted	277,781	275,851
Earnings (losses) per share:
Diluted from continuing operations (in dollars per share)	$ (0.52)	$ (1.41)
Total Diluted (in dollars per share)	$ (0.52)	$ (1.41)
0.75% senior exchangeable notes due January 2024
Earnings (losses) per share:
Aggregate amount of senior notes	$ 575,000		$ 575,000
Interest rate on senior notes due (as a percent)	0.75%
Share issued price	$ 25.16		$ 25.16