Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Noncontrolling Interest in Consolidated Subsidiary [Member]
Balance, beginning (in shares) at Dec. 31, 2013		515,888,942.000000				75,638,654.000000
Balance, beginning at Dec. 31, 2013	$ 1,523.6	$ 5.2	$ 3,210.8	$ (47.4)	$ (1,105.3)	$ (572.5)	$ 32.8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive (loss) income	198.0			5.9	189.7		2.4
Stock option exercises (in shares)		3,735,048
Stock option exercises	24.9	$ 0.0	24.9
Shares issued pursuant to the employee stock purchase plan (in shares)		1,346,677
Shares issued pursuant to the employee stock purchase plan	10.0		10.0
Restricted stock units and stock grant awards issued (in shares)		3,644,895
Restricted stock units and stock grant awards issued	0.0
Shares withheld for employee taxes on restricted stock units (in shares)						(976,786)
Shares withheld for employee taxes on restricted stock units	(9.1)					$ (9.1)
Share-based compensation expense	$ 45.8		45.8
Repurchase of common stock (in shares)	(13,900,000)					(13,900,105)
Repurchase of common stock	$ (121.2)					$ (121.2)
Dividend to non-controlling shareholder of consolidated subsidiary	4.2
Dividend to non-controlling shareholder of consolidated subsidiary	(4.2)						(4.2)
Acquisition of non-controlling interest	(20.4)		(10.3)
Balance, ending (in shares) at Dec. 31, 2014		524,615,562				90,515,545.000000
Balance, ending at Dec. 31, 2014	1,647.4	$ 5.2	3,281.2	(41.5)	(915.6)	$ (702.8)	20.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive (loss) income	208.2			(0.8)	206.2		2.8
Stock option exercises (in shares)		3,487,238
Stock option exercises	27.1	$ 0.1	27.0
Shares issued pursuant to the employee stock purchase plan (in shares)		1,729,100
Shares issued pursuant to the employee stock purchase plan	14.6		14.6
Restricted stock units and stock grant awards issued (in shares)		4,302,821
Restricted stock units and stock grant awards issued	0.0
Shares withheld for employee taxes on restricted stock units (in shares)						(1,226,764)
Shares withheld for employee taxes on restricted stock units	(14.7)					$ (14.7)
Share-based compensation expense	$ 46.9		46.9
Repurchase of common stock (in shares)	(30,400,000)					(30,352,607)
Repurchase of common stock	$ (348.2)					$ (348.2)
Dividend to non-controlling shareholder of consolidated subsidiary	0.0
Warrants and bond hedge, net	(56.9)		(56.9)
Issuance of convertible notes	107.5		107.5
Balance, ending (in shares) at Dec. 31, 2015		534,134,721				122,094,916.000000
Balance, ending at Dec. 31, 2015	1,631.9	$ 5.3	3,420.3	(42.3)	(709.4)	$ (1,065.7)	23.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive (loss) income	$ 176.6			(7.9)	182.1		2.4
Stock option exercises (in shares)	1,800,000	1,849,777
Stock option exercises	$ 14.9	$ 0.1	14.8
Shares issued pursuant to the employee stock purchase plan (in shares)		1,813,789
Shares issued pursuant to the employee stock purchase plan	15.0		15.0
Restricted stock units and stock grant awards issued (in shares)		4,519,501
Restricted stock units and stock grant awards issued	0.0
Shares withheld for employee taxes on restricted stock units (in shares)						(1,281,159)
Shares withheld for employee taxes on restricted stock units	(12.3)					$ (12.3)
Share-based compensation expense	$ 56.1		56.1
Repurchase of common stock (in shares)	0
Reclassification of 2.625% Notes, Series B -Convertible equity component to mezzanine equity	$ (32.9)		(32.9)
Dividend to non-controlling shareholder of consolidated subsidiary	4.3
Dividend to non-controlling shareholder of consolidated subsidiary	(4.3)
Balance, ending (in shares) at Dec. 31, 2016		542,317,788				123,376,075
Balance, ending at Dec. 31, 2016	$ 1,845.0	$ 5.4	$ 3,473.3	$ (50.2)	$ (527.3)	$ (1,078.0)	$ 21.8