Subsequent Event - Additional Information (Detail) - Subsequent Event [Member] shares in Thousands, $ in Millions	Nov. 08, 2021 USD ($) shares
Inmarsat [Member]
Subsequent Event [Line Items]
Principal amount of senior secured debt	$ 2,100.0
Outstanding borrowings under the Credit Facility	1,700.0
Financing commitments	2,400.0
Inmarsat [Member]
Subsequent Event [Line Items]
Consideration payable under the Share Purchase Agreement in cash, subject to adjustments	$ 850.0
Consideration payable under the Share Purchase Agreement in common stock, subject to adjustments | shares	46,360
Termination fee payable upon termination of the Share Purchase Agreement under certain circumstances	$ 200.0
Reimbursement of certain out-of-pocket expenses of certain sellers upon termination of the Share Purchase Agreement under certain circumstances	40.0
Financing commitments in connection with acquisition	2,300.0
Commitment obtained to backstop certain amendments required under current credit facilities	$ 3,200.0