Note 15 - Segment Reporting - Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021
Revenues from external customers									$ 176,759	$ 145,619
Revenue from Contract with Customer, Including Assessed Tax	$ 40,060	$ 44,843	$ 50,012	$ 41,844	$ 26,011	$ 40,389	$ 46,491	$ 32,728	176,759	145,619
Operating (loss) income	(2,102)	$ (520)	$ (1,912)	$ (2,073)	(3,975)	$ (1,997)	$ (2,311)	$ (4,311)	(6,607)	(12,594)
Depreciation and amortization									6,060	6,336
Capital expenditures									3,098	1,707
Total assets	144,540				118,047				144,540	118,047
Consolidation, Eliminations [Member]
Revenues from external customers									0	0
Revenue from Contract with Customer, Including Assessed Tax									(839)	(360)
Operating (loss) income									(4)	0
Depreciation and amortization									0	0
Capital expenditures									0	0
Total assets	(190,510)				(204,347)				(190,510)	(204,347)
Intersegment Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax									0	0
Heavy Fabrications [Member]
Operating (loss) income									(1,044)	(3,214)
Total assets	45,475				37,131				45,475	37,131
Heavy Fabrications [Member] | Operating Segments [Member]
Revenues from external customers									117,194	101,989
Revenue from Contract with Customer, Including Assessed Tax									117,206	101,994
Depreciation and amortization									3,446	3,844
Capital expenditures									2,601	1,038
Heavy Fabrications [Member] | Intersegment Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax									12	5
Gearing [Member]
Operating (loss) income									43	(2,593)
Total assets	51,944				46,219				51,944	46,219
Gearing [Member] | Operating Segments [Member]
Revenues from external customers									42,572	28,583
Revenue from Contract with Customer, Including Assessed Tax									42,588	28,583
Depreciation and amortization									1,978	1,855
Capital expenditures									446	328
Gearing [Member] | Intersegment Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax									16	0
Industrial Solutions [Member]
Operating (loss) income									120	(386)
Total assets	12,775				10,825				12,775	10,825
Industrial Solutions [Member] | Operating Segments [Member]
Revenues from external customers									16,993	15,047
Revenue from Contract with Customer, Including Assessed Tax									17,804	15,402
Depreciation and amortization									397	425
Capital expenditures									48	261
Industrial Solutions [Member] | Intersegment Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax									811	355
Corporate Segment [Member]
Operating (loss) income									(5,722)	(6,401)
Total assets	$ 224,856				$ 228,219				224,856	228,219
Corporate Segment [Member] | Operating Segments [Member]
Revenues from external customers									0	0
Revenue from Contract with Customer, Including Assessed Tax									0	0
Depreciation and amortization									239	212
Capital expenditures									3	80
Corporate Segment [Member] | Intersegment Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax									$ 0	$ 0