v3.26.1
Basis of Presentation - Summary of Disaggregation of Revenue by Segment and Products and Services (Detail) - USD ($)
$ in Thousands
 3 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Disaggregation Of Revenue [Line Items]    
Total revenues $ 1,156,543 $ 1,171,054
Service [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues 832,438 826,370
Product [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues 324,105 344,684
Operating Segments [Member] | Communication Services [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues 825,083 827,371
Operating Segments [Member] | Communication Services [Member] | Service [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues 773,042 777,198
Operating Segments [Member] | Communication Services [Member] | Product [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues 52,041 50,173
Operating Segments [Member] | Defense and Advanced Technologies [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues 331,460 343,683
Operating Segments [Member] | Defense and Advanced Technologies [Member] | Service [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues 59,396 49,172
Operating Segments [Member] | Defense and Advanced Technologies [Member] | Product [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenues $ 272,064 $ 294,511