Income Taxes - Narrative (Details) € in Millions, $ in Millions			12 Months Ended
	Aug. 22, 2019 USD ($)	Aug. 15, 2017 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)	Apr. 26, 2019 USD ($)	Nov. 29, 2018 EUR (€)	Dec. 31, 2017 USD ($)
Operating Loss Carryforwards [Line Items]
Dividends received deduction (percent)			100.00%
Unrecognized tax benefits liability, interest and penalties accrued			$ 98.1	$ 86.8							$ 82.0
Unrecognized tax benefits that would impact effective tax rate			204.6	203.7							$ 204.0
Income tax examination, debts subject to limit of deductibility of interest expense	$ 7,500.0
Interest rate cap on debts for U.S. tax purposes, as percent of applicable Federal rate	130.00%
Income tax examination, reduction in blended interest rate due to cap for U.S. Federal tax purposes	4.00%
IRS notice of proposed audit adjustment to reduce deductible interest expense for fiscal years 2014 and 2015	$ 480.0
Income tax examination, estimated increase to tax expense from audit adjustment to fiscal years 2014 and 2015, excluding interest and penalties	170.0
Income tax examination, estimate of additional tax expense for the period from June 28, 2015 through December 31, 2019, excluding interest and penalties	$ 200.0
Income tax examination, penalties and interest expense		$ 163.6			$ 24.7	$ 40.2	$ 61.5	$ 37.2
Income tax overpayments applied to succeeding years			$ 29.7
Royalty conceded on all omeprazole sales as a percent of refund claims (percent)			24.00%
IRS notice of proposed audit adjustment from 2011, 2012, and 2013 audit of Athena, including penalty									$ 843.0
IRS notice of proposed adjustment, penalty (percent)									40.00%
Tax cuts and jobs act of 2017, change in tax rate, income tax expense (benefit)				(2.4)
Tax cuts and jobs act, transition tax for accumulated foreign earnings				17.5
Tax cuts and jobs act 2017, undistributed accumulated earnings of foreign subsidiary				1,200.0
Tax cuts and jobs act of 2017, transition tax for accumulated foreign earnings, provisional income tax expense (benefit)			$ 6.3
Tax cuts and jobs act of 2017, change in tax rate, provisional income tax expense (benefit)			$ 8.3
Irish Revenue
Operating Loss Carryforwards [Line Items]
Unsettled audit assessment from income tax examination | €										€ 1,636
Belgium Taxing Authority
Operating Loss Carryforwards [Line Items]
Income tax expense as a result of Belgium Tax Act				24.1
Income tax benefit as a result of Belgium Tax Act				$ 33.2