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, 2024	Mar. 31, 2023	Mar. 31, 2022
Disaggregation Of Revenue [Line Items]
Total revenues	$ 4,283,758	$ 2,556,158	$ 2,417,179
Product [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	1,279,164	954,126	860,726
Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	3,004,594	1,602,032	1,556,453
Operating Segments [Member] | Satellite Services [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	2,141,775	1,210,733	1,188,816
Operating Segments [Member] | Satellite Services [Member] | Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	2,141,775	1,210,733	1,188,816
Operating Segments [Member] | Commercial Networks [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	777,841	612,647	512,099
Operating Segments [Member] | Commercial Networks [Member] | Product [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	685,868	530,374	443,435
Operating Segments [Member] | Commercial Networks [Member] | Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	91,973	82,273	68,664
Operating Segments [Member] | Government Systems [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	1,364,142	732,778	716,264
Operating Segments [Member] | Government Systems [Member] | Product [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	593,296	423,752	417,291
Operating Segments [Member] | Government Systems [Member] | Service [Member]
Disaggregation Of Revenue [Line Items]
Total revenues	$ 770,846	$ 309,026	$ 298,973