Note 4 - Revenue Recognition - Disaggregation of Revenues, Percentage (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Percentage of net sales	100.00%	100.00%	100.00%
Carbon Flat Products [Member]
Percentage of net sales	26.30%	30.30%	25.40%
Specialty Metals Flat Products [Member]
Percentage of net sales	56.60%	53.00%	58.10%
Tubular and Pipe Products [Member]
Percentage of net sales	17.10%	16.70%	16.50%
Hot Rolled Products [Member]
Percentage of net sales	28.80%	29.80%	31.40%
Hot Rolled Products [Member] | Carbon Flat Products [Member]
Percentage of net sales	28.80%	0.00%	0.00%
Hot Rolled Products [Member] | Specialty Metals Flat Products [Member]
Percentage of net sales	0.00%	29.80%	31.40%
Hot Rolled Products [Member] | Tubular and Pipe Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%
Plate Products [Member]
Percentage of net sales	12.90%	13.30%	10.40%
Plate Products [Member] | Carbon Flat Products [Member]
Percentage of net sales	12.90%	0.00%	0.00%
Plate Products [Member] | Specialty Metals Flat Products [Member]
Percentage of net sales	0.00%	13.30%	10.40%
Plate Products [Member] | Tubular and Pipe Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%
Cold Rolled Products [Member]
Percentage of net sales	4.00%	4.70%	7.00%
Cold Rolled Products [Member] | Carbon Flat Products [Member]
Percentage of net sales	4.00%	0.00%	0.00%
Cold Rolled Products [Member] | Specialty Metals Flat Products [Member]
Percentage of net sales	0.00%	4.70%	7.00%
Cold Rolled Products [Member] | Tubular and Pipe Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%
Coated Products [Member]
Percentage of net sales	10.30%	4.50%	7.70%
Coated Products [Member] | Carbon Flat Products [Member]
Percentage of net sales	10.30%	0.00%	0.00%
Coated Products [Member] | Specialty Metals Flat Products [Member]
Percentage of net sales	0.00%	4.50%	7.70%
Coated Products [Member] | Tubular and Pipe Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%
Specialty [Member]
Percentage of net sales	26.30%	30.30%	25.30%
Specialty [Member] | Carbon Flat Products [Member]
Percentage of net sales	0.00%	30.30%	25.30%
Specialty [Member] | Specialty Metals Flat Products [Member]
Percentage of net sales	26.30%	0.00%	0.00%
Specialty [Member] | Tubular and Pipe Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%
Pipe and Tube Products [Member]
Percentage of net sales	17.10%	16.70%	16.50%
Pipe and Tube Products [Member] | Carbon Flat Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%
Pipe and Tube Products [Member] | Specialty Metals Flat Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%
Pipe and Tube Products [Member] | Tubular and Pipe Products [Member]
Percentage of net sales	17.10%	16.70%	16.50%
Product and Service, Other [Member]
Percentage of net sales	0.60%	0.70%	1.70%
Product and Service, Other [Member] | Carbon Flat Products [Member]
Percentage of net sales	0.60%	0.00%	0.10%
Product and Service, Other [Member] | Specialty Metals Flat Products [Member]
Percentage of net sales	0.00%	0.70%	1.60%
Product and Service, Other [Member] | Tubular and Pipe Products [Member]
Percentage of net sales	0.00%	0.00%	0.00%