Unaudited Condensed Consolidated Statement of Equity - USD ($) $ in Thousands	Total	Stockholders' Equity [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Non-controlling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASC 606	$ (3,365)	$ (3,365)			$ (3,365)
Beginning balance at Dec. 31, 2017	264,080	263,990	$ 209	$ 199,474	64,307	$ 90
Beginning Balance, Shares at Dec. 31, 2017			20,876,837
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(651)	(640)			(640)	(11)
Stock-based compensation expense	842	842		842
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans	(954)	(954)		(954)
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans, shares			(83,816)
Shares issued through stock plans	0	0	$ 1	(1)
Shares issued through stock plans, shares			214,881
Ending balance at Mar. 31, 2018	259,952	259,873	$ 210	199,361	60,302	79
Ending Balance, Shares at Mar. 31, 2018			21,007,902
Beginning balance at Dec. 31, 2018	$ 240,030	239,954	$ 201	193,132	46,621	76
Beginning Balance, Shares at Dec. 31, 2018	20,058,904		20,058,904
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ (1,987)	(1,987)			(1,987)	0
Stock-based compensation expense	566	566		566
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans	(488)	(488)		(488)
Shares net settled with the Company to satisfy employee personal income tax liabilities resulting from share based compensation plans, shares			(85,420)
Shares issued through stock plans	0	0	$ 1	(1)
Shares issued through stock plans, shares			229,545
Repurchase of common stock, Shares			(153,916)
Repurchase of common stock	(1,042)	(1,042)	$ (2)	(1,040)	0
Ending balance at Mar. 31, 2019	$ 237,079	$ 237,003	$ 200	$ 192,169	$ 44,634	$ 76
Ending Balance, Shares at Mar. 31, 2019	20,049,113		20,049,113