Executive Bonus Plan	9 Months Ended
Sep. 30, 2023
Compensation Related Costs [Abstract]
Executive Bonus Plan	Executive Bonus PlanFor the three months ended September 30, 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 $5,081 and $8,454, respectively, and $17,326 and $24,984 for the nine months ended September 30, 2023 and 2022, 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
-Topic 710
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//710/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 710
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482969/710-10-50-1

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