Organization and Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Cash and cash equivalents	$ 55,902	$ 34,598
Restricted cash	86,761	54,106
Total cash, cash equivalents, and restricted cash shown on consolidated statement of cash flows	$ 142,663	$ 88,704	$ 86,384	$ 87,200