Inventories (Tables)

6 Months Ended

Jun. 30, 2017

Inventory Disclosure [Abstract]

Schedule of Inventory, Current [Table Text Block]

	June 30, 2017		December 31, 2016
Finished goods	$	22,506	$	21,635
Parts and materials	11,762		11,185
Work in progress	1,330		900
Total inventories	$	35,598	$	33,720