Business Segment Information - Property And Equipment Net Of Accumulated Depreciation By Geographic Region (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Property and equipment, net	$ 1,805,989	$ 1,651,610
United States [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	894,680	956,458
United Kingdom [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	270,499	299,699
Brazil [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	334,454	123,461
Singapore [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	295,798	194,649
Other [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	$ 10,558	$ 77,343