Summary of Non-Monetary Long-Lived Assets by Geographic Region (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Revenue from External Customer [Line Items]
Total long-lived assets	$ 2,010,142	$ 1,999,339
United States
Revenue from External Customer [Line Items]
Total long-lived assets	1,183,791	1,183,938
Europe
Revenue from External Customer [Line Items]
Total long-lived assets	823,657	812,833
Rest of World
Revenue from External Customer [Line Items]
Total long-lived assets	$ 2,694	$ 2,568