Stockholders' Equity and Equity Instruments - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ (53.0)	$ 38.6	$ (15.5)	$ 34.5
Other comprehensive income (loss) before reclassifications	(37.7)	(28.9)	(76.9)	(24.8)
Amounts reclassified from accumulated other comprehensive income (loss)	0.5	0.3	2.2	0.3
Net current period other comprehensive income (loss)	(37.2)	(28.6)	(74.7)	(24.5)
Ending balance	(90.2)	10.0	(90.2)	10.0
Losses (gains) on foreign exchange of intercompany notes of long-term nature	13.0	10.4	27.6	10.8
Gains and (Losses) on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(1.5)	0.4	(2.0)	0.3
Other comprehensive income (loss) before reclassifications	(0.3)	(0.5)	(0.9)	0.2
Amounts reclassified from accumulated other comprehensive income (loss)	0.3	0.0	1.4	(0.6)
Net current period other comprehensive income (loss)	0.0	(0.5)	0.5	(0.4)
Ending balance	(1.5)	(0.1)	(1.5)	(0.1)
Defined Benefit Pension [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(8.4)	(8.7)	(9.0)	(9.3)
Other comprehensive income (loss) before reclassifications	0.0	0.0	0.0	0.0
Amounts reclassified from accumulated other comprehensive income (loss)	0.2	0.3	0.8	0.9
Net current period other comprehensive income (loss)	0.2	0.3	0.8	0.9
Ending balance	(8.2)	(8.4)	(8.2)	(8.4)
Foreign Currency [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(43.1)	46.9	(4.5)	43.5
Other comprehensive income (loss) before reclassifications	(37.4)	(28.4)	(76.0)	(25.0)
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0	0.0	0.0
Net current period other comprehensive income (loss)	(37.4)	(28.4)	(76.0)	(25.0)
Ending balance	$ (80.5)	$ 18.5	$ (80.5)	$ 18.5