Supplemental Cash Flow Information - Schedule of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash and Cash Equivalents [Line Items]
Cash, cash equivalents, and restricted cash	$ 96,790	$ 60,507	$ 75,710	$ 94,907
Restricted cash - long-term	3,437	3,437	2,672	0
Restricted cash (note 18)	3,071	2,153	1,599	750
Cash and cash equivalents	88,824	54,917	71,439	94,157
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	23,725	0
Cash, cash equivalents and restricted cash
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	1,121
Cash and Cash Equivalents [Domain]
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents		0	0	0
Restricted Cash [Member]
Cash and Cash Equivalents [Line Items]
Restricted cash (note 18)		$ 0	$ 0	$ 0
Restricted Cash and Cash Equivalents	$ 337

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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