Cover - shares	3 Months Ended
	Mar. 31, 2022	May 03, 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	001-39548
Entity Registrant Name	BENTLEY SYSTEMS, INCORPORATED
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	95-3936623
Entity Address, Address Line One	685 Stockton Drive
Entity Address, City or Town	Exton
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19341
City Area Code	610
Local Phone Number	458-5000
Title of 12(b) Security	Class B Common Stock, par value $0.01 per share
Trading Symbol	BSY
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
Current Fiscal Year End Date	--12-31
Central Index Key	0001031308
Amendment Flag	false
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2022
Class A Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		11,601,757
Class B Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		275,932,539