Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Schedule of Reconciliation of Cash and Cash Equivalents, and Restricted Cash (Details)

v3.19.2
Summary of Significant Accounting Policies - Schedule of Reconciliation of Cash and Cash Equivalents, and Restricted Cash (Details) - USD ($)
$ in Thousands
Jun. 30, 2019
Dec. 31, 2018
Jun. 30, 2018
Accounting Policies [Abstract]      
Cash and cash equivalents $ 19,390 $ 125,298 $ 25,420
Restricted cash 15 $ 15 15
Total cash, cash equivalents, and restricted cash shown in the statements of cash flows $ 19,405   $ 25,435