Segment Information - Segment Revenues and Operating Profits (Losses) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Revenues:
Total revenues	$ 2,787,635	$ 2,256,107	$ 2,309,238
Operating profits (losses):
Income from operations	8,330	58,233	38,421
Amortization of acquired intangible assets	(28,729)	(5,482)	(7,611)
Product [Member]
Revenues:
Total revenues	1,210,411	1,044,450	1,172,541
Service [Member]
Revenues:
Total revenues	1,577,224	1,211,657	1,136,697
Operating Segments [Member]
Operating profits (losses):
Income from operations	37,059	63,715	46,032
Operating Segments [Member] | Satellite Services [Member]
Revenues:
Total revenues	1,188,816	868,943	826,583
Operating profits (losses):
Income from operations	42,862	35,853	7,015
Amortization of acquired intangible assets	(27,220)	(2,164)	(2,897)
Operating Segments [Member] | Satellite Services [Member] | Service [Member]
Revenues:
Total revenues	1,188,816	868,943	826,583
Operating Segments [Member] | Commercial Networks [Member]
Revenues:
Total revenues	512,099	320,856	344,557
Operating profits (losses):
Income from operations	(180,298)	(180,749)	(186,877)
Amortization of acquired intangible assets		(257)	(1,539)
Operating Segments [Member] | Commercial Networks [Member] | Product [Member]
Revenues:
Total revenues	443,435	268,830	289,959
Operating Segments [Member] | Commercial Networks [Member] | Service [Member]
Revenues:
Total revenues	68,664	52,026	54,598
Operating Segments [Member] | Government Systems [Member]
Revenues:
Total revenues	1,086,720	1,066,308	1,138,098
Operating profits (losses):
Income from operations	174,495	208,611	225,894
Amortization of acquired intangible assets	(1,509)	(3,061)	(3,175)
Operating Segments [Member] | Government Systems [Member] | Product [Member]
Revenues:
Total revenues	766,976	775,620	882,582
Operating Segments [Member] | Government Systems [Member] | Service [Member]
Revenues:
Total revenues	319,744	290,688	255,516
Material Reconciling Items [Member]
Operating profits (losses):
Amortization of acquired intangible assets	$ (28,729)	$ (5,482)	$ (7,611)