Note 2 - Revenues - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Revenues	$ 46,598	$ 57,163	$ 50,843	$ 48,873	$ 40,060	$ 44,843	$ 50,012	$ 41,844	$ 203,477	$ 176,759
Consolidation, Eliminations [Member]
Revenues									(458)	(839)
Heavy Fabrications [Member] | Operating Segments [Member]
Revenues									133,368	117,206
Gearing [Member] | Operating Segments [Member]
Revenues									45,408	42,588
Industrial Solutions [Member] | Operating Segments [Member]
Revenues									$ 25,159	$ 17,804