STOCKHOLDERS' EQUITY - Accumulated Other Comprehensive Income (Loss) Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ (591.2)	$ (629.6)	$ (649.6)	$ (429.8)
Other comprehensive income before reclassifications	(66.4)	83.5	(8.7)	(121.9)
Amounts reclassified from AOCI	1.3	(2.6)	2.0	3.0
Other comprehensive income (loss)	(65.1)	80.9	(6.7)	(118.9)
Ending balance	(656.3)	(548.7)	(656.3)	(548.7)
Cumulative Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(430.8)	(457.1)	(492.7)	(245.5)
Other comprehensive income before reclassifications	(72.4)	85.4	(10.5)	(126.2)
Amounts reclassified from AOCI	0.0	0.0	0.0	0.0
Other comprehensive income (loss)	(72.4)	85.4	(10.5)	(126.2)
Ending balance	(503.2)	(371.7)	(503.2)	(371.7)
Deriviatve Hedging Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(1.3)	(0.4)	2.3	(0.7)
Other comprehensive income before reclassifications	(1.1)	5.8	(3.5)	3.0
Amounts reclassified from AOCI	(0.1)	(5.0)	(1.3)	(1.9)
Other comprehensive income (loss)	(1.2)	0.8	(4.8)	1.1
Ending balance	(2.5)	0.4	(2.5)	0.4
Unrealized Gains and Losses on Debt and Equity Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(6.7)	(1.5)	(6.3)	1.6
Other comprehensive income before reclassifications	2.7	(2.3)	2.3	(5.4)
Amounts reclassified from AOCI	0.0	0.0	0.0	0.0
Other comprehensive income (loss)	2.7	(2.3)	2.3	(5.4)
Ending balance	(4.0)	(3.8)	(4.0)	(3.8)
Pension Liability Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(152.4)	(170.6)	(152.9)	(185.2)
Other comprehensive income before reclassifications	4.4	(5.4)	3.0	6.7
Amounts reclassified from AOCI	1.4	2.4	3.3	4.9
Other comprehensive income (loss)	5.8	(3.0)	6.3	11.6
Ending balance	$ (146.6)	$ (173.6)	$ (146.6)	$ (173.6)