Revenue Recognition - Contract Cost (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 [Roll Forward]
Beginning of period balance	$ 77	$ 75	$ 76	$ 78
Costs incurred	14	15	29	29
Amortization	(13)	(15)	(27)	(32)
Change in contract costs held for sale (1)	0	0	0	0
End of period balance	78	75	78	75
Fulfillment Costs (1)
Capitalized Contract Cost [Roll Forward]
Beginning of period balance	100	123	99	122
Costs incurred	22	23	43	46
Amortization	(20)	(22)	(40)	(44)
Change in contract costs held for sale (1)	(1)	0	(1)	0
End of period balance	101	124	101	124
Fulfillment Costs (1) | Discontinued Operations, Held-for-sale
Capitalized Contract Cost [Roll Forward]
Beginning of period balance	$ 27		$ 27
End of period balance		$ 28		$ 28