The Company and a Summary of Its Significant Accounting Policies - Summary of Disaggregation of Revenue by Segment and Product and Services (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Disaggregation Of Revenue [Line Items]
Total revenues	$ 2,556,158	$ 2,417,179	$ 1,920,878
Product [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	954,126	860,726	739,373
Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	1,602,032	1,556,453	1,181,505
Operating Segments [Member] | Satellite Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	1,210,733	1,188,816	868,943
Operating Segments [Member] | Satellite Services [Member] | Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	1,210,733	1,188,816	868,943
Operating Segments [Member] | Commercial Networks [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	612,647	512,099	320,856
Operating Segments [Member] | Commercial Networks [Member] | Product [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	530,374	443,435	268,830
Operating Segments [Member] | Commercial Networks [Member] | Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	82,273	68,664	52,026
Operating Segments [Member] | Government Systems [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	732,778	716,264	731,079
Operating Segments [Member] | Government Systems [Member] | Product [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	423,752	417,291	470,543
Operating Segments [Member] | Government Systems [Member] | Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	$ 309,026	$ 298,973	$ 260,536