XML 107 R76.htm IDEA: XBRL DOCUMENT v3.19.1
Short Term Investments (Details) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Subclassifications of assets, liabilities and equities [abstract]    
Short-term investments (Note 9) $ 74,004 $ 51,590
Short-term investments, cost 73,796 49,985
Short-term investments, accumulated unrealized holding gains $ 208 $ 1,605