XML 44 R31.htm IDEA: XBRL DOCUMENT v3.8.0.1
Other Assets (Tables)
12 Months Ended
Dec. 31, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]  
Schedule of Other Assets

Other assets consist of the following:

 

December 31,  2017   2016 
         
Patents, at cost  $6,814   $6,525 
Accumulated amortization   (4,202)   (3,915)
Deposits on capital items   7,958    21,436 
Other   3,169    3,495 
   $13,739   $27,541