Segment Reporting and Information about Geographic Areas - Schedule of Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived Assets	$ 16,092,566	$ 17,601,473
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived Assets	15,577,311	16,741,409
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived Assets	$ 515,255	$ 860,064