Segment Information - Segment Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 6,389,346	$ 5,349,467
Operating Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	1,127,083	702,771
Operating Segments [Member] | Satellite Services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	444,976	64,048
Operating Segments [Member] | Commercial Networks [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	202,941	168,334
Operating Segments [Member] | Government Systems [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	479,166	470,389
Corporate, Non-Segment [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 5,262,263	$ 4,646,696