Income Taxes (Details) € in Millions, $ in Millions		3 Months Ended		12 Months Ended
	Aug. 15, 2017 USD ($)	Mar. 30, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)	Nov. 29, 2018 EUR (€)
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, percent		21.10%	26.90%
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%
Income tax benefit			$ 2.4
Tax expense in connection with Transition Toll Tax			$ 17.5
Foreign earnings				$ 1,200.0
Tax Cuts and Jobs Act of 2017, change in tax rate, 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
Global intangible low-taxed income, income tax expense (benefit)				$ 9.4
Revenue Commissioners, Ireland
Income Tax Contingency [Line Items]
Unsettled audit assessment from income tax examination | €									€ 1,636