Revenue - Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Contract with Customer, Asset, after Allowance for Credit Loss, Current	$ 1,470.0		$ 1,470.0		$ 1,520.0
Contract (liabilities)	4,643.4		4,643.4		4,585.1
Net contract liabilities	(3,173.4)		(3,173.4)		$ (3,065.1)
Contract assets, increase (decrease)			$ (50.0)
Contract with Customer, Asset, Net, Current, Increase (Decrease), Percent			(3.30%)
Contract (liabilities), (increase) decrease			$ (58.3)
Contract with Customer Liability, Current, Increase (Decrease), Percent			1.30%
Net contract assets (liabilities), increase (decrease)			$ (108.3)
Contract Assets (Liabilities), Current, Net, Increase (Decrease), Percent			(3.50%)
Contract with Customer, Liability, Revenue Recognized	228.1	$ 503.6	$ 1,102.5	$ 1,984.4
Contract with Customer, Performance Obligation Satisfied in Previous Period	$ 181.1	$ 281.7	$ 340.0	$ 775.1