Other Financial Data - Schedule of Other Current Liabilities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Other Financial Data [Abstract]
Deferred revenue	$ 256		$ 256		$ 251
Leases	218		218
Taxes payable	152		152		83
Other	537		537		602
Total	1,163		1,163		$ 936
Revenue recognized from deferred revenue	$ 144	$ 133	$ 385	$ 348