Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of cash, cash equivalents, and restricted cash to balance sheet:
Cash and cash equivalents - unrestricted	$ 56,697	$ 362,430	$ 103,437
Cash and cash equivalents - restricted	23,057	57,966	45,652
Cash, cash equivalents, and restricted cash, end of period	$ 79,754	$ 420,396	$ 149,089	$ 78,710