Financial Instruments and Fair Value Measurement - Pretax Derivative Accumulated Other Comprehensive Loss (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Cumulative Changes in Derivative Net Gain (Loss) [Roll Forward]
Beginning balance	$ 2,856.6
Ending balance	2,571.1
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Cumulative Changes in Derivative Net Gain (Loss) [Roll Forward]
Beginning balance	(10.9)
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	(2.6)
Current Period Change in Fair Value	0.9
Ending balance	$ (12.6)

Cumulative Changes in Derivative Net Gain (Loss) [Roll Forward]

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- Definition

Amount of ownership interest in limited liability company (LLC), attributable to the parent entity.

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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