Business Segments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) segment	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment	2
Segment Reporting Information [Line Items]
Revenues	$ 23,033	$ 17,664
Depreciation	2,322	2,225
Loss from operations before equity income	(392)	1
Net equity income from foreign joint ventures' operations	87	354
Income (loss) from operations	(305)	355
Interest income (expense), net	(154)	(17)
Interest expense, net - related parties	(31)	(173)
Income tax expense (benefit)	(129)	80
Net income (loss)	(406)	175
Total assets	86,603		$ 87,336
LNG
Segment Reporting Information [Line Items]
Revenues	20,267	16,120
Depreciation	2,277	2,188
Loss from operations before equity income	(295)	268
Net equity income from foreign joint ventures' operations	0	0
Income (loss) from operations	(295)	268
Interest income (expense), net	(137)	(7)
Interest expense, net - related parties	(31)	(173)
Income tax expense (benefit)	(132)	44
Net income (loss)	(376)	15
Total assets	68,903		70,735
Power Delivery
Segment Reporting Information [Line Items]
Revenues	2,766	1,544
Depreciation	45	37
Loss from operations before equity income	(97)	(267)
Net equity income from foreign joint ventures' operations	87	354
Income (loss) from operations	(10)	87
Interest income (expense), net	(17)	(10)
Interest expense, net - related parties	0	0
Income tax expense (benefit)	3	36
Net income (loss)	(30)	$ 160
Total assets	$ 17,700		$ 16,601