Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2021

Revenue From Contract With Customer [Abstract]

Summary of Percent of Revenues

The following table discloses the percent of the Company’s revenue generated from time and materials contracts:

	Fiscal Years
	2021	2020	2019
Engineering & Other Scientific	61%	61%	66%
Environmental and Health	17%	19%	18%
Total time and materials revenues	78%	80%	84%

The following table discloses the percent of the Company’s revenue generated from fixed price contracts:  

	Fiscal Years
	2021	2020	2019
Engineering & Other Scientific	21%	19%	15%
Environmental and Health	1%	1%	1%
Total fixed price revenues	22%	20%	16%