XML 57 R43.htm IDEA: XBRL DOCUMENT v3.19.1
Composition of Certain Financial Statement Captions - Other Assets (Details) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Other Assets [Abstract]    
Long-term supplies $ 1,540 $ 2,181
Deposits 365 389
Total other assets $ 1,905 $ 2,570