CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) shares in Millions, $ in Millions	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Beginning Balance at Dec. 31, 2017	$ 2,908.6		$ 0.9	$ 1,153.2	$ 2,029.5	$ (287.0)	$ 12.0
Beginning Balance (in shares) at Dec. 31, 2017		0.7	85.5
Cumulative effect of new accounting standard, net of tax	13.0				13.0
Net (loss) income	50.1				50.2		(0.1)
Currency translation adjustment	(59.9)					(59.3)	(0.6)
Change in qualifying cash flow hedge, net of tax	0.5					0.5
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net	8.4			8.4
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net (in shares)			0.2
Repurchase and cancellation of convertible preferred stock	(14.8)			(29.3)	14.5
Repurchase and cancellation of convertible preferred stock (in shares)		(0.1)
Preferred stock dividend	(17.1)				(17.1)
Stock compensation expense	12.8			12.8
Ending Balance at Jun. 30, 2018	2,901.6		$ 0.9	1,145.1	2,090.1	(345.8)	11.3
Ending Balance (in shares) at Jun. 30, 2018		0.6	85.7
Beginning Balance at Mar. 31, 2018	2,952.1		$ 0.9	1,146.3	2,063.5	(270.7)	12.1
Beginning Balance (in shares) at Mar. 31, 2018		0.7	85.6
Net (loss) income	27.6				27.7		(0.1)
Currency translation adjustment	(76.2)					(75.5)	(0.7)
Change in qualifying cash flow hedge, net of tax	0.4					0.4
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net	7.7			7.7
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net (in shares)			0.1
Repurchase and cancellation of convertible preferred stock	(7.4)			(14.6)	7.2
Repurchase and cancellation of convertible preferred stock (in shares)		(0.1)
Preferred stock dividend	(8.3)				(8.3)
Stock compensation expense	5.7			5.7
Ending Balance at Jun. 30, 2018	2,901.6		$ 0.9	1,145.1	2,090.1	(345.8)	11.3
Ending Balance (in shares) at Jun. 30, 2018		0.6	85.7
Beginning Balance at Dec. 31, 2018	2,597.1		$ 0.9	1,162.6	1,789.2	(365.3)	9.7
Beginning Balance (in shares) at Dec. 31, 2018			90.7
Net (loss) income	(67.8)				(68.3)		0.5
Currency translation adjustment	6.1					5.8	0.3
Change in qualifying cash flow hedge, net of tax	0.6					0.6
Accelerated amortization of cash flow hedge, net of tax	2.3					2.3
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net	13.9			13.9
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net (in shares)			0.4
Stock compensation expense	10.0			10.0
Payments to noncontrolling interest				6.3			(6.3)
Ending Balance at Jun. 30, 2019	2,562.2		$ 0.9	1,192.8	1,720.9	(356.6)	4.2
Ending Balance (in shares) at Jun. 30, 2019			91.1
Beginning Balance at Mar. 31, 2019	2,570.5		$ 0.9	1,171.2	1,751.4	(356.9)	3.9
Beginning Balance (in shares) at Mar. 31, 2019			90.8
Net (loss) income	(30.2)				(30.5)		0.3
Currency translation adjustment	(2.4)					(2.4)
Change in qualifying cash flow hedge, net of tax	0.4					0.4
Accelerated amortization of cash flow hedge, net of tax	2.3					2.3
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net	15.9			15.9
Issuance of common stock for exercise of options, RSU vesting, and employee stock purchases, net (in shares)			0.3
Stock compensation expense	5.7			5.7
Ending Balance at Jun. 30, 2019	$ 2,562.2		$ 0.9	$ 1,192.8	$ 1,720.9	$ (356.6)	$ 4.2
Ending Balance (in shares) at Jun. 30, 2019			91.1