Commitments and Contingencies - Contingencies - Additional Information (Detail) € in Millions, $ in Millions					1 Months Ended				3 Months Ended	12 Months Ended
	Nov. 20, 2020 EUR (€)	Oct. 21, 2019 USD ($) Number	Aug. 21, 2017 USD ($)	Jul. 15, 2015 USD ($)	May 31, 2019 USD ($)	Aug. 31, 2012 USD ($)	Dec. 31, 2010 USD ($)	Aug. 31, 2008 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2014 USD ($)	Sep. 01, 2020 USD ($)	Jan. 31, 2009 USD ($)	Jul. 31, 2008 USD ($)	Feb. 28, 2005 USD ($)
Commitment And Contingencies [Line Items]
Damages assessment									$ 235.5
Annual sales at the time of settlement												$ 700.0	$ 350.0
Annual sales of Effexor			$ 2,600.0
Annual sales of Lamictal														$ 2,300.0	$ 950.0
Annual sales of Aggrenox				$ 1.1				$ 416.0
Annual sales of Actos						$ 2,800.0	$ 3,700.0
Annual sales of Acto plus						$ 430.0	$ 500.0
Annual Sales Of Sensipar										$ 1,400.0
Litigation settlement amount awarded cash amount		$ 20.0
Annual Sales Of Copaxone											$ 380.0
Fines Imposed In Period | €	€ 60.5
Opioid Litigation [Member]
Commitment And Contingencies [Line Items]
Litigation settlement amount		$ 25.0			$ 85.0
Litigation settlement amount awarded distribution period		3 years
Litigation settlement amount awarded number of installments | Number		4
Litigation settlement amount awarded cash amount distribution period		3 years
Nationwide Settlement [Member]
Commitment And Contingencies [Line Items]
Litigation settlement amount		$ 23,000.0
Litigation settlement amount awarded distribution period		10 years
Litigation settlement amount awarded cash amount		$ 250.0
Litigation settlement amount awarded cash amount distribution period		10 years
Eosinophilic Esophagitis [Member]
Commitment And Contingencies [Line Items]
Damage claimed									200.0
Eosinophilic Esophagitis [Member] | United States [Member]
Commitment And Contingencies [Line Items]
Damage claimed									150.0
Eosinophilic Esophagitis [Member] | Europe [Member]
Commitment And Contingencies [Line Items]
Damage claimed									$ 50.0
AndroGel Rate at 1% [Member]
Commitment And Contingencies [Line Items]
Annual sales at the time of settlement													$ 140.0