Note 2 - Revenues - Disaggregation of Revenue (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	$ 40,060	$ 44,843	$ 50,012	$ 41,844	$ 26,011	$ 40,389	$ 46,491	$ 32,728	$ 176,759	$ 145,619
Consolidation, Eliminations [Member]
Revenues									(839)	(360)
Heavy Fabrications [Member] | Operating Segments [Member]
Revenues									117,206	101,994
Gearing [Member] | Operating Segments [Member]
Revenues									42,588	28,583
Industrial Solutions [Member] | Operating Segments [Member]
Revenues									$ 17,804	$ 15,402