Revenue Recognition - Percentage of Sales by Major Product Lines (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Product Line
Percentage of sales by major product lines	100.00%	100.00%	100.00%	100.00%
Carbon Steel Flat [Member]
Product Line
Percentage of sales by major product lines	29.00%	31.00%	30.00%	30.00%
Carbon Steel Plate [Member]
Product Line
Percentage of sales by major product lines	10.00%	10.00%	10.00%	10.00%
Carbon Steel Long [Member]
Product Line
Percentage of sales by major product lines	13.00%	13.00%	13.00%	13.00%
Stainless Steel Flat [Member]
Product Line
Percentage of sales by major product lines	18.00%	17.00%	18.00%	17.00%
Stainless Steel Plate [Member]
Product Line
Percentage of sales by major product lines	4.00%	5.00%	5.00%	5.00%
Stainless Steel Long [Member]
Product Line
Percentage of sales by major product lines	5.00%	4.00%	5.00%	4.00%
Aluminum Flat [Member]
Product Line
Percentage of sales by major product lines	13.00%	13.00%	12.00%	13.00%
Aluminum Plate [Member]
Product Line
Percentage of sales by major product lines	2.00%	2.00%	2.00%	2.00%
Aluminum Long [Member]
Product Line
Percentage of sales by major product lines	4.00%	4.00%	4.00%	4.00%
Other [Member]
Product Line
Percentage of sales by major product lines	2.00%	1.00%	1.00%	2.00%