Software Development and Intellectual Property Licenses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Software development and intellectual property licenses:
Internally-developed software costs	$ 436		$ 436		$ 345
Payments made to third-party software developers	29		29		31
Total software development costs	465		465		$ 376
Amortization:
Amortization of capitalized software development costs and intellectual property licenses	$ 30	$ 54	$ 112	$ 164