Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement of Comprehensive Income [Abstract]
Net sales	$ 1,406.1	$ 1,748.8
Cost of materials sold	1,141.9	1,338.7
Gross profit	264.2	410.1
Warehousing, delivery, selling, general, and administrative	194.2	175.3
Operating profit	70.0	234.8
Other income and (expense), net	0.1	(5.7)
Interest and other expense on debt	(7.6)	(10.3)
Income before income taxes	62.3	218.8
Provision for income taxes	14.8	55.0
Net income	47.5	163.8
Less: Net income attributable to noncontrolling interest	0.2	0.2
Net income attributable to Ryerson Holding Corporation	47.3	163.6
Comprehensive income	48.2	166.7
Less: Comprehensive income attributable to noncontrolling interest	0.1	0.2
Comprehensive income attributable to Ryerson Holding Corporation	$ 48.1	$ 166.5
Basic earnings per share	$ 1.30	$ 4.26
Diluted earnings per share	1.27	4.17
Dividends declared per share	$ 0.17	$ 0.10