Summary of Significant Accounting Policies (Reconciliation of Cash, Cash Equivalents, and Restricted Cash) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Accounting Policies [Abstract]
Cash and cash equivalents	$ 238,305	$ 193,411
Restricted cash and cash equivalents included in other assets	1,438	1,438
Total cash, cash equivalents, and restricted cash shown in the condensed consolidated statements of cash flows	$ 239,743	$ 194,849	$ 395,084	$ 365,677