Note 13 - Segment Reporting - Revenues by Geography (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
Revenue		$ 46,919	$ 37,068
Well Enhancement Services Segment [Member]
Revenue		42,759	34,686
Water Transfer Services Segment [Member]
Revenue		4,160	2,128
Rocky Mountain Region [Member] | Well Enhancement Services Segment [Member]
Revenue	[1]	27,582	23,514
Rocky Mountain Region [Member] | Water Transfer Services Segment [Member]
Revenue	[1]	4,160	2,128
Central USA Region [Member] | Well Enhancement Services Segment [Member]
Revenue	[2]	10,950	9,613
Central USA Region [Member] | Water Transfer Services Segment [Member]
Revenue	[2]
Eastern USA Region [Member] | Well Enhancement Services Segment [Member]
Revenue	[3]	4,227	1,813
Eastern USA Region [Member] | Water Transfer Services Segment [Member]
Revenue	[3]

[1] Includes the D-J Basin/Niobrara field (northeastern Colorado and southeastern Wyoming), the San Juan Basin (southeastern Colorado and northeastern New Mexico), the Powder River and Green River Basins (northeastern and southwestern Wyoming), the Bakken area (western North Dakota and eastern Montana).

[2] Includes the Scoop/Stack Shale in Oklahoma and the Eagle Ford Shale.

[3] Consists of the southern region of the Marcellus Shale formation (southwestern Pennsylvania and northern West Virginia) and the Utica Shale formation (eastern Ohio).