Leases (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Operating lease assets	$ 434.4	$ 434.4	$ 0.0
Long-term operating lease liabilities	423.0	423.0	0.0
Operating lease liabilities	495.3	495.3
Operating lease cost	14.4	30.1
Net lease cost	14.4	30.1
ASC 842 - Minimum lease payments 2019 (remaining six months)	50.2	50.2
ASC 842 - Minimum lease payments, 2020	80.5	80.5
ASC 842 - Minimum lease payments, 2021	74.9	74.9
ASC 842 - Minimum lease payments, 2022	70.9	70.9
ASC 842 - Minimum lease payments, 2023	69.4	69.4
ASC 842 - Minimum lease payments, 2024	66.7	66.7
ASC 842 - Minimum lease payments, thereafter	147.6	147.6
ASC 842 - Minimum lease payments	560.2	560.2
Less: Interest	$ 64.9	$ 64.9
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 940 - 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
ASC 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
Weighted average remaining lease term in years	7 years 4 months 24 days	7 years 4 months 24 days
Weighted average discount rate	3.30%	3.30%
Cash paid for amounts included in measurement of lease liabilities	$ 27.4	$ 46.8
Operating lease assets obtained in exchange for lease obligations	7.3	12.7
Research and development
Operating lease cost	3.4	3.7
Net lease cost	3.4	3.7
Selling, general and administrative
Operating lease cost	17.9	41.4
Sublease income	(6.0)	(13.1)
Net lease cost	17.9	41.4
Other income (expense)
Sublease income	(0.9)	(1.9)
Operating lease assets
Operating lease assets	434.4	434.4
Accrued expenses and other
Operating lease liability, current	72.3	72.3
Long-term operating lease liabilities
Long-term operating lease liabilities	$ 423.0	$ 423.0

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