Segment Information - Long-Lived Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Company's long-lived assets	$ 10,898,210	$ 10,732,909	$ 11,026,020
Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Company's long-lived assets	4,982,068		5,010,507
EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Company's long-lived assets	3,773,205		3,726,596
Asia-Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Company's long-lived assets	$ 2,142,937		$ 2,288,917