Employee Benefit Plans	12 Months Ended
Dec. 31, 2021
Compensation Related Costs [Abstract]
Employee Benefit Plans	10. EMPLOYEE BENEFIT PLANS The Company provides a 401(k) plan that covers substantially all U.S. employees. Participants can elect to contribute up to 50% of their eligible earnings on a pre-tax basis, subject to Internal Revenue Service annual limitations. The U.S.-based plan offers a year-end employer matching contribution, requiring the participant to be an employee at year-end to qualify for the match. Participants with one year or more of service are eligible for the matching contribution. Participants fully vest in the employer contributions after three years of service. The employer contribution represents a percentage of a participant’s eligible compensation. The Company’s 401(k) Plan costs were $4.3 million, $3.7 million and $3.1 million during the years ended December 31, 2021, 2020 and 2019, respectively, and were allocated between Total direct costs, and Selling, general and administrative in the consolidated statements of operations. The Company has various defined contribution arrangements for eligible employees of non-U.S. entities. These defined contribution arrangements provide employees with retirement savings and life insurance benefits. The Company incurred expenses related to these arrangements of $1.9 million, $1.5 million and $1.2 million in the years ended December 31, 2021, 2020 and 2019, respectively, and were allocated between Total direct costs, and Selling, general and administrative in the consolidated statements of operations. The Company is also required to pay certain minimum statutory post-employment benefits. The Company recognizes a liability and the associated expense for these benefits when it is probable that employees are entitled to the benefit.

Employee Benefit Plans

12 Months Ended

Dec. 31, 2021

10. EMPLOYEE BENEFIT PLANS

The Company provides a 401(k) plan that covers substantially all U.S. employees. Participants can elect to contribute up to 50% of their eligible earnings on a pre-tax basis, subject to Internal Revenue Service annual limitations.

The U.S.-based plan offers a year-end employer matching contribution, requiring the participant to be an employee at year-end to qualify for the match. Participants with one year or more of service are eligible for the matching contribution. Participants fully vest in the employer contributions after three years of service. The employer contribution represents a percentage of a participant’s eligible compensation. The Company’s 401(k) Plan costs were $4.3 million, $3.7 million and $3.1 million during the years ended December 31, 2021, 2020 and 2019, respectively, and were allocated between Total direct costs, and Selling, general and administrative in the consolidated statements of operations.

The Company has various defined contribution arrangements for eligible employees of non-U.S. entities. These defined contribution arrangements provide employees with retirement savings and life insurance benefits. The Company incurred expenses related to these arrangements of $1.9 million, $1.5 million and $1.2 million in the years ended December 31, 2021, 2020 and 2019, respectively, and were allocated between Total direct costs, and Selling, general and administrative in the consolidated statements of operations.

The Company is also required to pay certain minimum statutory post-employment benefits. The Company recognizes a liability and the associated expense for these benefits when it is probable that employees are entitled to the benefit.