Segments - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Revenues	$ 23,708		$ 13,483		$ 36,632	$ 22,601
Total cost of revenues	17,455		11,267		27,243	18,811
Gross profit	6,253		2,216		9,389	3,790
Selling, general and administrative	6,420		5,339		11,679	9,433
Amortization of intangible assets	785		590		1,509	1,032
Income (loss) from operations	(952)		(3,713)		(3,799)	(6,675)
EBITDA	5,452		(3,252)		3,386	(5,127)
Depreciation and amortization	(1,464)		(795)		(2,746)	(1,483)
Interest income (expense), net	(80)		221		(98)	595
Income tax benefit (provision)	(457)		39		1,733	4
Net Income (loss)	3,451	$ (1,176)	(3,787)	$ (2,224)	2,275	(6,011)
Energy Services
Segment Reporting Information [Line Items]
Revenues	3,324		0		4,130	0
Operating segments | Building Solutions
Segment Reporting Information [Line Items]
Revenues	20,384		13,483		32,502	22,601
Total cost of revenues	15,141		11,254		24,330	18,694
Gross profit	5,243		2,229		8,172	3,907
Selling, general and administrative	3,286		2,481		6,194	4,615
Amortization of intangible assets	687		590		1,411	1,032
Income (loss) from operations	1,270		(842)		567	(1,740)
EBITDA	2,214		(203)		2,545	(525)
Depreciation and amortization	(965)		(774)		(1,978)	(1,341)
Interest income (expense), net	(163)		(138)		(345)	(174)
Income tax benefit (provision)	0		0		0	0
Net Income (loss)	1,086		(1,115)		222	(2,040)
Operating segments | Energy Services
Segment Reporting Information [Line Items]
Revenues	3,324		0		4,130	0
Total cost of revenues	2,240		0		2,764	0
Gross profit	1,084		0		1,366	0
Selling, general and administrative	877		0		1,151	0
Amortization of intangible assets	98		0		98	0
Income (loss) from operations	109		0		117	0
EBITDA	530		0		720	0
Depreciation and amortization	(417)		0		(600)	0
Interest income (expense), net	(97)		0		(96)	0
Income tax benefit (provision)	0		0		0	0
Net Income (loss)	16		0		24	0
Operating segments | Investments
Segment Reporting Information [Line Items]
Revenues	158		194		316	382
Total cost of revenues	74		13		149	117
Gross profit	84		181		167	265
Selling, general and administrative	84		1,372		134	1,412
Amortization of intangible assets	0		0		0	0
Income (loss) from operations	0		(1,191)		33	(1,147)
EBITDA	5,033		(1,451)		4,605	(1,075)
Depreciation and amortization	(74)		(13)		(149)	(117)
Interest income (expense), net	166		199		321	390
Income tax benefit (provision)	0		0		0	0
Net Income (loss)	5,125		(1,265)		4,777	(802)
Corporate and Intersegment eliminations
Segment Reporting Information [Line Items]
Revenues	(158)		(194)		(316)	(382)
Total cost of revenues	0		0		0	0
Gross profit	(158)		(194)		(316)	(382)
Selling, general and administrative	2,173		1,486		4,200	3,406
Amortization of intangible assets	0		0		0	0
Income (loss) from operations	(2,331)		(1,680)		(4,516)	(3,788)
EBITDA	(2,325)		(1,598)		(4,484)	(3,527)
Depreciation and amortization	(8)		(8)		(19)	(25)
Interest income (expense), net	14		160		22	379
Income tax benefit (provision)	(457)		39		1,733	4
Net Income (loss)	$ (2,776)		$ (1,407)		$ (2,748)	$ (3,169)