Cover Page - shares	3 Months Ended
	Mar. 31, 2022	Apr. 29, 2022
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	0-25092
Entity Registrant Name	INSIGHT ENTERPRISES, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	86-0766246
Entity Address, Address Line One	2701 E. Insight Way
Entity Address, City or Town	Chandler
Entity Address, State or Province	AZ
Entity Address, Postal Zip Code	85286
City Area Code	480
Local Phone Number	333-3000
Title of 12(b) Security	Common stock, par value $0.01
Trading Symbol	NSIT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		35,074,362
Entity Central Index Key	0000932696
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Filer Category	Large Accelerated Filer
Former Address
Document Information [Line Items]
Entity Address, Address Line One	6820 South Harl Avenue
Entity Address, City or Town	Tempe
Entity Address, State or Province	AZ
Entity Address, Postal Zip Code	85283