Segment and Geographic Area Information Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Cash and cash equivalents	$ 80,472	$ 32,319	$ 35,941	$ 59,727
Property and equipment, net	4,656,921	4,503,319
North American Operations [Member]
Segment Reporting Information [Line Items]
Cash and cash equivalents	13,584	10,137
Property and equipment, net	3,657,801	3,590,625
Australian Operations [Member]
Segment Reporting Information [Line Items]
Cash and cash equivalents	52,407	9,213
Property and equipment, net	664,367	634,148
U.K./European Operations [Member]
Segment Reporting Information [Line Items]
Cash and cash equivalents	14,481	12,969
Property and equipment, net	$ 334,753	$ 278,546