Basis of Presentation - Summary of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Cash and Cash Equivalents		$ 9,506	$ 10,740	$ 24,924	$ 18,026
Restricted Cash		50	951	0	37,505
Cash, Cash Equivalents, and Restricted Cash	[1]	$ 9,556	$ 11,691	$ 24,924	$ 55,531

[1] See Note 2. Basis of Presentation for our reconciliation of total cash.