Acquisition (Australia Expansion) (Details) - USD ($)
$ in Thousands
12 Months Ended
Apr. 01, 2016
Dec. 31, 2016
Dec. 31, 2015
Purchase Agreement      
Goodwill   $ 14,100 $ 2,780
Australia Expansion      
Purchase Agreement      
Total consideration transferred $ 700    
Goodwill $ 300