Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 546,675	$ 339,629	$ 274,122
Restricted cash	196,385	186,921	198,123
Total Cash and cash equivalents and Restricted cash shown in the Consolidated Statements of Cash Flows	$ 743,060	$ 526,550	$ 472,245	$ 583,572