Hedging transactions and derivative financial instruments Hedging transactions and derivative financial instruments (Derivative and Nonderivative Debt Instruments) (Details) - Net investment hedging $ in Millions	Dec. 31, 2019 USD ($)
Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	$ 25.7
Accrued expenses and other liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	111.7
Long-term debt
Derivatives, Fair Value [Line Items]
Nonderivative hedging instruments	$ 6,275.9