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EARNINGS (LOSS) PER SHARE (Details) $ / shares in Units, $ in Millions		3 Months Ended						9 Months Ended
	Sep. 30, 2018 USD ($) item $ / shares	Sep. 30, 2018 USD ($) $ / shares shares	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Sep. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2017 USD ($) $ / shares shares	Sep. 14, 2018 USD ($) $ / shares
Numerator:
Net earnings (loss) from continuing operations		$ (100.4)	$ 22.2	$ 17.7	$ (42.7)	$ (176.5)	$ 8.4	$ (60.5)	$ (210.8)
Denominator (shares in thousands):
Weighted average shares for basic earnings (loss) per common share \| shares		123,126,000			131,077,000			126,386,000	127,902,000
Shares for diluted earnings (loss) per common share \| shares		123,126,000			131,077,000			126,386,000	127,902,000
Basic earnings (loss) per common share (in dollars per share) \| $ / shares		$ (0.82)			$ (0.33)			$ (0.48)	$ (1.65)
Diluted earnings (loss) per common share (in dollars per share) \| $ / shares		$ (0.82)			$ (0.33)			$ (0.48)	$ (1.65)
Interest Expense		$ 84.0			$ 71.4			$ 248.9	$ 203.4
Derivative liability	$ 144.5	$ 144.5						$ 144.5
Senior Unsecured Convertible Notes due 2024
Denominator (shares in thousands):
Number of shares upon conversion		5,900,000						2,000,000
Conversion rate (in dollars per share) \| $ / shares										$ 18.95
Interest Expense		$ 1.5
Derivative liability	$ 144.5	$ 144.5						$ 144.5		$ 90.4
Senior Unsecured Convertible Notes due 2024 \| Class A common stock
Denominator (shares in thousands):
Number of shares upon conversion	31,662,269							31,662,269
Conversion rate (in dollars per share) \| $ / shares	$ 18.95	$ 18.95						$ 18.95
Senior Unsecured Convertible Notes due 2024 \| Charges to Earnings
Denominator (shares in thousands):
Derivative liability	$ 54.1	$ 54.1						$ 54.1
Performance Vesting
Denominator (shares in thousands):
Anti-dilutive securities not included in the computations of diluted earnings per share (in shares) \| shares								411,657
Restricted stock unit
Denominator (shares in thousands):
Anti-dilutive securities not included in the computations of diluted earnings per share (in shares) \| shares								902,004