Investments (Details) - USD ($) $ in Millions			12 Months Ended
		Jun. 17, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Purchase of equity method investment			$ 15.0	$ 0.0	$ 0.0
Impact of ASU 2016-01			5,655.1	5,803.8	5,668.0		$ 6,170.5
Other (income) expense, net
Schedule of Equity Method Investments [Line Items]
Equity securities, fair value method, other expense (inxcome)			3.0	4.9	9.5
Equity securites, equity method, other expense (income)			(3.0)	(2.7)	(2.7)
Kazmira, LLC
Schedule of Equity Method Investments [Line Items]
Equity method investments		$ 50.0
Ownership interest (percent)		20.00%
Purchase of equity method investment		$ 15.0
Period for payment of balance of equity method investment		18 months
Retained Earnings (Accumulated Deficit)
Schedule of Equity Method Investments [Line Items]
Impact of ASU 2016-01			(1,858.1)	(1,695.5)	$ (1,838.3)		$ (1,975.5)
Retained Earnings (Accumulated Deficit) | ASU 2016-01
Schedule of Equity Method Investments [Line Items]
Impact of ASU 2016-01						$ 1.0
Prepaid expenses and other current assets
Schedule of Equity Method Investments [Line Items]
Equity securities, fair value method			2.5	6.6
Other non-current assets
Schedule of Equity Method Investments [Line Items]
Equity securities, fair value method	[1]		1.9	2.3
Equity method investments			$ 69.8	$ 17.8

[1] (1) Measured at fair value using the Net Asset Value practical expedient.