Other Consolidated Financial Statement Detail - Accrued Expenses and Other (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Revenue-related reserves for discounts and allowances	$ 1,276.0	$ 1,198.9	$ 1,051.3	$ 761.6
Total accrued expenses and other	3,145.3	2,765.8
Component of accrued expenses and other
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Revenue-related reserves for discounts and allowances	1,080.6	1,001.1
Collaboration expenses	389.9	281.6
Employee-related Liabilities, Current	333.8	309.1
Accrued Royalties, Current	218.5	220.9
Derivative liabilities	181.5	6.7
Business Combination, Contingent Consideration, Liability, Current	149.6	148.4
Other Accrued Liabilities, Current	791.4	798.0
Total accrued expenses and other	$ 3,145.3	$ 2,765.8