Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Jul. 25, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2019
Entity File Number	001-36860
Entity Registrant Name	IOVANCE BIOTHERAPEUTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	75-3254381
Entity Address, Address Line One	999 Skyway Road, Suite 150
Entity Address, City or Town	San Carlos
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94070
City Area Code	650
Local Phone Number	260-7120
Title of 12(b) Security	Common stock, par value $0.000041666 per value
Trading Symbol	IOVA
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		123,830,506
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001425205
Amendment Flag	false