Earnings (Loss) per Ordinary Share (Basic and Diluted Earnings Per Ordinary Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Earnings Per Share [Abstract]
Net earnings (loss) attributable to Viatris Inc. common shareholders	$ 94.8	$ 331.6	$ (117.7)	$ 820.3
Weighted average shares outstanding	1,193.5	1,199.5	1,193.3	1,200.4
Basic earnings (loss) per share attributable to Viatris Inc. shareholders	$ 0.08	$ 0.28	$ (0.10)	$ 0.68
Weighted average number diluted shares outstanding adjustment, stock-based awards and warrants	6.9	8.1	0.0	5.2
Total dilutive shares outstanding	1,200.4	1,207.6	1,193.3	1,205.6
Diluted earnings (loss) per ordinary share	$ 0.08	$ 0.27	$ (0.10)	$ 0.68