Segment Reporting and Information about Geographic Areas - Schedule of Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived Assets	$ 16,744	$ 16,534
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived Assets	15,657	15,644
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived Assets	$ 1,087	$ 890