Inventories (Allowance) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for excess and obsolete inventories:
Balance, beginning of period	$ 714	$ 579	$ 363
Provisions for excess and obsolete inventories	178	135	243
Inventories written off	(135)	0	(27)
Balance, end of period	$ 757	$ 714	$ 579