Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Summary of Significant Accounting Policies
Period to amortize assets recognized related to costs to obtain subscriber contract			1 year
Contract cost capitalized during the period	$ 24	$ 32	$ 68	$ 93
Amortization expense related to the programs	37	$ 41	118	$ 116
Total costs capitalized	$ 248		$ 248		$ 298