Segment Information - Reportable Segment Total Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total assets	$ 4,886,742	$ 4,871,065
U.S.
Segment Reporting Information [Line Items]
Total assets	3,971,289	4,087,039
U.K.
Segment Reporting Information [Line Items]
Total assets	784,896	654,154
Brazil
Segment Reporting Information [Line Items]
Total assets	$ 130,557	$ 129,872