Goodwill and Acquired Intangible Assets - Schedule of Goodwill by Segments (Detail) - USD ($) $ in Thousands	Mar. 31, 2025	Mar. 31, 2024
Goodwill [Line Items]
Goodwill	$ 1,622,132	$ 1,621,763
Communication Services [Member]
Goodwill [Line Items]
Goodwill	1,582,083	1,581,937
Defense and Advanced Technologies [Member]
Goodwill [Line Items]
Goodwill	$ 40,049	$ 39,826