Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Restricted Cash (Details)

v3.19.1
Summary of Significant Accounting Policies - Restricted Cash (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Mar. 31, 2018
Accounting Policies [Abstract]      
Restricted cash non-current $ 20,920 $ 19,637 $ 20,778