Business Segments (Details) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment					2
Total revenues	$ 5,003		$ 11,095		$ 18,841	$ 24,070
Depreciation	2,266		2,295		4,536	4,585
Loss from operations before equity income	(3,972)		(723)		(4,605)	(926)
Net equity income from foreign joint ventures' operations	948		0		774	0
Income (loss) from operations	(3,024)		(723)		(3,831)	(926)
Net loss	(3,463)	$ (1,050)	(1,038)	$ (559)	(4,513)	(1,597)
Total assets	81,610				81,610		$ 90,326
LNG
Segment Reporting Information [Line Items]
Total revenues	4,027		11,095		16,555	24,070
Depreciation	2,234		2,295		4,469	4,585
Loss from operations before equity income	(3,531)		(723)		(3,730)	(926)
Net equity income from foreign joint ventures' operations	0				0
Income (loss) from operations	(3,531)				(3,730)
Net loss	(3,740)		(1,038)		(4,220)	(1,597)
Total assets	67,358				67,358		75,883
Power Delivery
Segment Reporting Information [Line Items]
Total revenues	976		0		2,286	0
Depreciation	32		0		67	0
Loss from operations before equity income	(441)		0		(875)	0
Net equity income from foreign joint ventures' operations	948				774
Income (loss) from operations	507				(101)
Net loss	277		$ 0		(293)	$ 0
Total assets	$ 14,252				$ 14,252		$ 14,443
Bomay
Segment Reporting Information [Line Items]
Ownership percentage	40.00%				40.00%