Leases Leases (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Operating lease assets	$ 427.0	$ 0.0
Operating lease liability, noncurrent	412.7	0.0
Operating lease liabilities	486.3
Net lease cost	86.7
ASC 842 - Minimum lease payments, 2020	87.6
ASC 842 - Minimum lease payments, 2021	81.5
ASC 842 - Minimum lease payments, 2022	75.7
ASC 842 - Minimum lease payments, 2023	72.5
ASC 842 - Minimum lease payments, 2024	69.0
ASC 842 - Minimum lease payments, thereafter	158.3
Total lease payments	544.6
Less: interest	$ 58.3
ASC 840 - Minimum lease payments, 2019		87.0
ASC 840 - Minimum lease payments, 2020		80.7
ASC 840 - Minimum lease payments, 2021		75.9
ASC 840 - Minimum lease payments, 2022		71.7
ASC 840 - Minimum lease payments, 2023		71.0
ASC 840 - Minimum lease payments, thereafter		215.3
ASC 840 - Minimum lease payments, total		601.6
ASC 840 - Sublease income, 2019		(26.8)
ASC 840 - Sublease income, 2020		(25.6)
ASC 840 - Sublease income, 2021		(23.7)
ASC 840 - Sublease income, 2022		(24.0)
ACS 840 - Sublease income, 2023		(24.3)
ASC 840 - Sublease income, thereafter		(58.4)
ASC 840 - Sublease income, total		(182.8)
ASC 840 - Net minimum lease payments, 2019		60.2
ASC 840 - Net minimum lease payments, 2020		55.1
ASC 840 - Net minimum lease payments, 2021		52.2
ASC 840 - Net minimum lease payments, 2022		47.7
ASC 840 - Net minimum lease payments, 2023		46.7
ASC 840 - Net minimum lease payments, thereafter		156.9
ASC 840 - Net minimum lease payments, total		$ 418.8
Operating Lease, Weighted Average Remaining Lease Term	7 years 25 days
Operating Lease, Weighted Average Discount Rate, Percent	3.20%
Operating Lease, Payments	$ 93.8
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	35.9
Operating lease assets [Member]
Operating lease assets	427.0
Accrued expenses and other
Operating lease liability, current	73.6
Long-term operating lease liabilities [Member]
Operating lease liability, noncurrent	412.7
Research and development
Operating lease cost	6.7
Variable lease cost	1.2
Selling, General and Administrative Expenses
Operating lease cost	84.6
Variable lease cost	23.7
Sublease income	(25.6)
Other income (expense)
Sublease income	$ (3.9)

Net minimum lease payments total.

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