Executive Bonus Plan	3 Months Ended
Mar. 31, 2023
Compensation Related Costs [Abstract]
Executive Bonus Plan	Executive Bonus PlanFor the three months ended March 31, 2023 and 2022, the incentive compensation, including cash payments, election to receive shares of fully vested Class B Common Stock, and deferred compensation to plan participants, recognized under the amended and restated Bentley Systems, Incorporated Bonus Pool Plan (the “Bonus Plan”) (net of all applicable holdbacks) was $7,948 and $9,719, respectively.

The entire disclosure for compensation costs, including compensated absences accruals, compensated absences liability, deferred compensation arrangements and income statement compensation items. Deferred compensation arrangements may include a description of an arrangement with an individual employee, which is generally an employment contract between the entity and a selected officer or key employee containing a promise by the employer to pay certain amounts at designated future dates, usually including a period after retirement, upon compliance with stipulated requirements. This type of arrangement is distinguished from broader based employee benefit plans as it is usually tailored to the employee. Disclosure also typically includes the amount of related compensation expense recognized during the reporting period, the number of shares (units) issued during the period under such arrangements, and the carrying amount as of the balance sheet date of the related liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-URI https://asc.fasb.org/topic&trid=2127225

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6409950&loc=d3e20396-108366

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