Segment Operating Results - Assets by Geographic Area (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total Assets	$ 3,370,888	$ 2,598,613	$ 2,125,667
United States [Member]
Segment Reporting Information [Line Items]
Total Assets	2,862,343	2,158,347
Europe And Other [Member]
Segment Reporting Information [Line Items]
Total Assets	504,977	373,822
Latin America [Member]
Segment Reporting Information [Line Items]
Total Assets	$ 3,568	$ 66,444