Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Oct. 23, 2019
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	0-26301
Entity Registrant Name	United Therapeutics Corporation
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	52-1984749
Entity Address, Address Line One	1040 Spring Street
Entity Address, City or Town	Silver Spring
Entity Address, State or Province	MD
Entity Address, Postal Zip Code	20910
City Area Code	301
Local Phone Number	608-9292
Security 12b Title	Common Stock, par value $0.01 per share
Trading Symbol	UTHR
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		43,881,350
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001082554
Amendment Flag	false