Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net sales	$ 1,743.5	$ 1,419.0	$ 3,492.3	$ 2,566.3
Cost of materials sold	1,277.6	1,162.0	2,616.3	2,111.4
Gross profit	465.9	257.0	876.0	454.9
Warehousing, delivery, selling, general, and administrative	182.9	178.3	358.2	350.1
Gain on sale of assets	(3.8)	(87.4)	(3.8)	(107.7)
Operating profit	286.8	166.1	521.6	212.5
Other income and (expense), net	(15.3)	(0.7)	(21.0)	(0.4)
Interest and other expense on debt	(8.3)	(13.6)	(18.6)	(27.1)
Income before income taxes	263.2	151.8	482.0	185.0
Provision for income taxes	66.8	38.5	121.8	46.1
Net income	196.4	113.3	360.2	138.9
Less: Net income attributable to noncontrolling interest		0.4	0.2	0.7
Net income attributable to Ryerson Holding Corporation	196.4	112.9	360.0	138.2
Comprehensive income	194.8	117.3	361.5	145.3
Less: Comprehensive income (loss) attributable to noncontrolling interest	(0.1)	0.5	0.1	0.7
Comprehensive income attributable to Ryerson Holding Corporation	$ 194.9	$ 116.8	$ 361.4	$ 144.6
Basic earnings per share	$ 5.20	$ 2.94	$ 9.45	$ 3.61
Diluted earnings per share	5.10	$ 2.91	9.26	$ 3.57
Dividends declared per share	$ 0.125		$ 0.225