SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS AND RESERVES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
ALLOWANCE FOR DOUBTFUL ACCOUNTS
VALUATION AND QUALIFYING ACCOUNTS AND RESERVES
Balance at beginning of period	$ 542	$ 419	$ 406
Additions charged to income	1,072	140	221
Accounts receivable written off	(191)	0	(13)
Other Adjustments	(449)	(17)	(195)
Balance at end of period	974	542	419
WARRANTY RESERVE
VALUATION AND QUALIFYING ACCOUNTS AND RESERVES
Balance at beginning of period	130	188	421
Additions charged to income	339	162	0
Accounts receivable written off	(308)	(216)	(117)
Other Adjustments	(31)	(4)	(116)
Balance at end of period	130	130	188
INVENTORY RESERVE
VALUATION AND QUALIFYING ACCOUNTS AND RESERVES
Balance at beginning of period	3,117	1,729	337
Additions charged to income	1,952	1,287	1,800
Accounts receivable written off	(1,160)	(77)	(408)
Other Adjustments	(227)	178	0
Balance at end of period	$ 3,682	$ 3,117	$ 1,729