Supplemental Cash Flow Information - Reconciliation of Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 8,301	$ 51,040	$ 12,326
Restricted cash and cash equivalents - current	516	1,269	11,787
Restricted cash and cash equivalents - long-term	2,258	1,999	2,565
Cash, cash equivalents, restricted cash, and restricted cash equivalents	$ 11,075	$ 54,308	$ 26,678	$ 43,267