Supplemental Cash Flow Information - Schedule of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 85,321	$ 78,861	$ 121,497	$ 172,680
Restricted cash	21,734	9,848	18,428	14,443
Total cash, cash equivalents and restricted cash	$ 107,055	$ 88,709	$ 139,925	$ 187,123