Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Jul. 31, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
Document Transition Report	false
Entity File Number	001-35418
Entity Registrant Name	EPAM SYSTEMS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	22-3536104
Entity Address, Street Name	41 University Drive
Entity Address, Suite No.	Suite 202
Entity Address, City or Town	Newtown
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	18940
City Area Code	267
Local Phone Number	759-9000
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	EPAM
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Central Index Key	0001352010
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		54,850,289
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false