Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 1,856,856	$ 750,147	$ 716,799
Restricted cash	104,999	117,151	30,857
Total Cash and cash equivalents and Restricted cash shown in the Consolidated Statements of Cash Flows	$ 1,961,855	$ 867,298	$ 747,656