Cover - shares	6 Months Ended
	Jun. 30, 2020	Jul. 31, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	001-33089
Entity Registrant Name	EXLSERVICE HOLDINGS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-0572194
Entity Address, Address Line One	320 Park Avenue,
Entity Address, Address Line Two	29th Floor,
Entity Address, City or Town	New York,
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10022
City Area Code	212
Local Phone Number	277-7100
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	EXLS
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		34,176,255
Entity Central Index Key	0001297989
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Amendment Flag	false