Revenue Recognition - Contract Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Acquisition Costs
Capitalized Contract Cost [Line Items]
Beginning of period balance	$ 63	$ 69	$ 64	$ 73
Costs incurred	12	13	25	24
Amortization	(13)	(14)	(27)	(29)
End of period balance	62	68	62	68
Fulfillment Costs
Capitalized Contract Cost [Line Items]
Beginning of period balance	47	52	47	54
Costs incurred	10	6	19	12
Amortization	(10)	(9)	(19)	(17)
End of period balance	$ 47	$ 49	$ 47	$ 49