Annual report pursuant to Section 13 and 15(d)

Business Segments and Customer Information - Major Customers (Details)

v3.22.0.1
Business Segments and Customer Information - Major Customers (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Revenue, Major Customer [Line Items]      
Revenues $ 750,853 $ 661,659 $ 752,627
Revenue from Contract with Customer Benchmark | Customer Concentration Risk      
Revenue, Major Customer [Line Items]      
Percentage of revenue by customer 100.00% 100.00% 100.00%
Commercial      
Revenue, Major Customer [Line Items]      
Revenues $ 322,318 $ 208,305 $ 242,518
Commercial | Revenue from Contract with Customer Benchmark | Customer Concentration Risk      
Revenue, Major Customer [Line Items]      
Percentage of revenue by customer 43.00% 31.00% 32.00%
DoD      
Revenue, Major Customer [Line Items]      
Revenues $ 233,422 $ 236,397 $ 304,334
DoD | Revenue from Contract with Customer Benchmark | Customer Concentration Risk      
Revenue, Major Customer [Line Items]      
Percentage of revenue by customer 31.00% 36.00% 41.00%
Other government      
Revenue, Major Customer [Line Items]      
Revenues $ 195,113 $ 216,957 $ 205,775
Other government | Revenue from Contract with Customer Benchmark | Customer Concentration Risk      
Revenue, Major Customer [Line Items]      
Percentage of revenue by customer 26.00% 33.00% 27.00%