Software Development and Intellectual Property Licenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Software development and intellectual property licenses:
Internally-developed software costs	$ 485	$ 345
Payments made to third-party software developers	27	31
Total software development costs	512	376
Amortization:
Amortization of capitalized software development costs and intellectual property licenses	$ 263	$ 241	$ 501