Disaggregated Revenue (Tables)

6 Months Ended

Jun. 30, 2019

Disaggregation Of Revenue [Abstract]

Schedule of Disaggregates Revenue by Product Line

The following table disaggregates revenue by product line:

	Three Months Ended				Six Months Ended
	June 30				June 30
	2019		2018		2019		2018
Oilfield and Industrial Technologies and Services segment
Technology products and services	$	8,426	$	12,786	$	15,615	$	22,656
Industrial products and services		3,141		3,269		7,868		6,562
Base ceramic and sand proppants		22,944		33,733		49,609		63,038
Sublease and rental income		1,402		—		2,908		—
		35,913		49,788		76,000		92,256
Environmental Technologies and Services segment		7,186		8,201		14,557		15,100
	$	43,099	$	57,989	$	90,557	$	107,356