Goodwill and Intangible Assets - Narrative (Details)	4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2021 USD ($)	Sep. 07, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2020 License
Goodwill And Intangible Assets Disclosure [Abstract]
Impairment losses recognized in goodwill	$ 0	$ 0	$ 0	$ 0
Finite-lived intangible assets	963,000,000.0		193,200,000
Indefinite-lived intangible assets	6,600,000
Number of wireless spectrum licenses | License					56
Number of locations with wireless spectrum licenses | License					17
Amortization of finite-lived intangible assets	41,400,000	9,900,000	14,400,000	14,700,000
Impairment of intangible assets, finite-lived	$ 0	$ 0	$ 0	$ 0