Cover - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Apr. 26, 2021	Jun. 26, 2020
Cover [Abstract]
Document Type	10-K/A
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-39695
Entity Registrant Name	VIATRIS INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-4364296
Entity Address, Address Line One	1000 Mylan Boulevard
Entity Address, City or Town	Canonsburg
Entity Address, Postal Zip Code	15317
Entity Address, State or Province	PA
City Area Code	(724)
Local Phone Number	514-1800
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	VTRS
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 0
Common Stock, Par or Stated Value Per Share	$ 0.01
Entity Common Stock, Shares Outstanding		1,208,643,411
Entity Central Index Key	0001792044
Amendment Flag	true
Amendment Description	This Amendment No. 1 on Form 10-K/A (this “Amendment”) amends our Annual Report on Form 10-K for the fiscal year ended December 31, 2020, originally filed on March 1, 2021 (the “Original Filing”). We are filing this Amendment to include the information required by Part III and not included in the Original Filing, as we do not intend to file a definitive proxy statement for an annual meeting of shareholders within 120 days of the end of our fiscal year ended December 31, 2020. In addition, in connection with the filing of this Amendment and pursuant to the rules of the Securities and Exchange Commission (the “SEC”), we are including with this Amendment new certifications of our principal executive officer and principal financial officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. Item 15 of Part IV has also been amended to reflect the filing of these new certifications and a corrected exhibit. Except as described above, no other changes have been made to the Original Filing. The Original Filing continues to speak as of the date of the Original Filing, and we have not updated the disclosures contained therein to reflect any events which occurred at a date subsequent to the filing of the Original Filing. As used in this Amendment, unless the context requires otherwise, the “Company,” “Viatris,” “our,” and “we” mean Viatris Inc. and its consolidated subsidiaries, “NASDAQ” means The NASDAQ Global Select Stock Market, and “U.S. GAAP” means accounting principles generally accepted in the United States (“U.S.”). On November 16, 2020, Viatris, formerly known as Upjohn Inc. (“Upjohn”), Mylan N.V. (“Mylan”) and Pfizer Inc. (“Pfizer”) consummated the combination of Mylan with Pfizer’s Upjohn business (the “Upjohn Business”) through a Reverse Morris Trust transaction. In accordance with the terms and conditions of the Business Combination Agreement, dated as of July 29, 2019, as amended from time to time, among Viatris, Mylan, Pfizer and certain of their affiliates (the “Business Combination Agreement”) and the Separation and Distribution Agreement between Viatris and Pfizer, dated as of July 29, 2019, as amended from time to time, (1) Pfizer contributed the Upjohn Business to Viatris so that the Upjohn Business was separated from the remainder of Pfizer’s businesses (the “Separation”), (2) following the Separation, Pfizer distributed, on a pro rata basis (based on the number of shares of Pfizer common stock held by holders of Pfizer common stock as of the record date of November 13, 2020 (the “Record Date”)), all of the shares of Viatris common stock held by Pfizer to Pfizer shareholders as of the Record Date (the “Distribution”), and (3) immediately following the Distribution, Viatris and Mylan engaged in a strategic business combination transaction (the “Combination”). As a result of the Combination, Viatris holds the combined Upjohn Business and Mylan business. In accordance with ASC 805, Business Combinations, Mylan is considered the accounting acquirer of the Upjohn Business and all historical financial information of the Company prior to November 16, 2020 represents Mylan’s historical results and the Company’s thereafter.
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31