Segment Reporting and Information about Geographic Areas - Schedule of Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Revenues From External Customers And Long Lived Assets [Line Items]
Long-lived Assets	$ 15,682,362	$ 11,902,839
United States [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Long-lived Assets	14,935,394	11,399,545
International [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Long-lived Assets	$ 746,968	$ 503,294