Reconciliation of Effective Income Tax Rate (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. federal statutory income tax rate										21.00%	21.00%	35.00%
Income tax provision at U.S. federal statutory rate										$ 184.5	$ 176.0	$ 294.3
State and local income taxes, net of federal income tax benefit										14.0	23.8	23.5
Impact of foreign operations, including withholding taxes										34.2	50.7	(6.7)
U.S. tax incentives										(21.4)	(17.5)	(1.3)
Change in net valuation allowance	[1]									(26.3)	(16.9)	1.4
Divestitures										9.6	11.7	1.1
U.S. federal tax credits										0.4	(48.1)	(0.4)
Stock compensation										(3.3)	(6.8)	(15.3)
Change in unrecognized tax benefits										14.1	8.4	7.0
Net impact of the Tax Act										0.0	13.4	(36.0)
Other										(1.0)	4.5	3.7
Provision for income taxes		$ 86.1	$ 64.6	$ 43.6	$ 10.5	$ 62.2	$ 60.7	$ 63.6	$ 12.7	$ 204.8	$ 199.2	$ 271.3
Effective income tax rate on operations										23.30%	23.80%	32.30%

[1] Reflects changes in valuation allowances that impacted the effective income tax rate for each year presented.