Note 15 - Segment Reporting - Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Revenues from external customers	$ 37,616		$ 48,873
Revenue from Contract with Customer, Including Assessed Tax	37,616	$ 48,873	48,873
Operating income (loss)	2,078	1,282	1,282
Depreciation and amortization	1,596	1,605	1,605
Capital expenditures	1,744		1,065
Total assets	123,071		135,156
Operating Segments [Member] | Heavy Fabrications [Member]
Revenues from external customers	22,016		31,593
Revenue from Contract with Customer, Including Assessed Tax	22,016	31,593	31,593
Operating income (loss)	2,046		2,790
Depreciation and amortization	911		858
Capital expenditures	461		662
Total assets	37,322		46,931
Operating Segments [Member] | Gearing [Member]
Revenues from external customers	8,337		11,965
Revenue from Contract with Customer, Including Assessed Tax	8,337	11,965	11,965
Operating income (loss)	25		581
Depreciation and amortization	540		596
Capital expenditures	1,068		385
Total assets	47,207		48,599
Operating Segments [Member] | Industrial Solutions [Member]
Revenues from external customers	7,263		5,315
Revenue from Contract with Customer, Including Assessed Tax	7,994	5,423	5,423
Operating income (loss)	1,767		622
Depreciation and amortization	100		94
Capital expenditures	215		18
Total assets	16,127		16,295
Operating Segments [Member] | Corporate Segment [Member]
Revenues from external customers	0		0
Revenue from Contract with Customer, Including Assessed Tax	0		0
Operating income (loss)	(1,760)		(2,711)
Depreciation and amortization	45		57
Capital expenditures	0		0
Total assets	52,329		58,487
Consolidation, Eliminations [Member]
Revenues from external customers	0		0
Revenue from Contract with Customer, Including Assessed Tax	(731)	$ (108)	(108)
Operating income (loss)	0		0
Depreciation and amortization	0		0
Capital expenditures	0		0
Total assets	(29,914)		(35,156)
Intersegment Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax	(731)		(108)
Intersegment Eliminations [Member] | Heavy Fabrications [Member]
Revenue from Contract with Customer, Including Assessed Tax	0		0
Intersegment Eliminations [Member] | Gearing [Member]
Revenue from Contract with Customer, Including Assessed Tax	0		0
Intersegment Eliminations [Member] | Industrial Solutions [Member]
Revenue from Contract with Customer, Including Assessed Tax	731		108
Intersegment Eliminations [Member] | Corporate Segment [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 0		$ 0