Summary of Significant Accounting Policies - Revenue by Contract Type (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Revenue By Contract Type [Line Items]
Revenue percent	100.00%	100.00%	100.00%
Time-and-material [Member]
Schedule Of Revenue By Contract Type [Line Items]
Revenue percent	79.80%	81.00%	79.60%
Progress Billing [Member]
Schedule Of Revenue By Contract Type [Line Items]
Revenue percent	17.80%	15.90%	10.20%
Percentage-of-completion [Member]
Schedule Of Revenue By Contract Type [Line Items]
Revenue percent	2.40%	3.10%	10.20%