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Goodwill and Other Intangibles (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Oct. 01, 2019	Dec. 31, 2019	Dec. 31, 2018
Beginning Balance		$ 11,082	$ 9,998
Acquisition of Mirabito and Prism (see Note 2)		1,744	1,084
Prism of acquisition purchase price allocation adjustment (see Note 2)		(280)
Impairment of Prism goodwill	$ (400)	(400)
Cumulative translation adjustment		(11)
Ending Balance		12,135	11,082
GRE [Member]
Beginning Balance		9,998	9,998
Acquisition of Mirabito and Prism (see Note 2)
Prism of acquisition purchase price allocation adjustment (see Note 2)
Impairment of Prism goodwill
Cumulative translation adjustment
Ending Balance		9,998	9,998
GRE International [Member]
Beginning Balance
Acquisition of Mirabito and Prism (see Note 2)		1,744
Prism of acquisition purchase price allocation adjustment (see Note 2)
Impairment of Prism goodwill
Cumulative translation adjustment		(11)
Ending Balance		1,733
GES [Member]
Beginning Balance		1,084
Acquisition of Mirabito and Prism (see Note 2)			1,084
Prism of acquisition purchase price allocation adjustment (see Note 2)		(280)
Impairment of Prism goodwill		(400)
Cumulative translation adjustment
Ending Balance		$ 404	$ 1,084