Condensed Consolidated Statements of Comprehensive Income Statement - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (1,068.1)	$ 459.8	$ (510.5)	$ 1,047.7
Other comprehensive loss, net of tax:
Foreign currency translation	1.5	1.5	(6.5)	(0.5)
Unrealized gains on debt securities	0.3	0.0	0.1	0.2
Unrealized losses on hedging activities, net of tax of $(3.3) $(12.1) $(11.5) and $(14.3), respectively	(11.2)	(38.9)	(37.7)	(47.9)
Other comprehensive loss, net of tax	(9.4)	(37.4)	(44.1)	(48.2)
Comprehensive (loss) income	$ (1,077.5)	$ 422.4	$ (554.6)	$ 999.5