Summary of Accounting and Financial Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2025 USD ($) Segment shares	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($)	Jun. 29, 2022 USD ($)	Jun. 28, 2022 USD ($)
Summary Of Accounting And Financial Policies [Line Items]
Parent company percentage owned by affiliates	12.20%
Parent company shares owned by affiliates \| shares	3,924,478
Treasury Stock, Common, Shares \| shares	8,164,148	8,051,226
Equity investments, income (loss)	$ (600,000)	$ 0	$ 100,000
Number of operating segment \| Segment	1
Book overdrafts	$ 72,600,000	74,200,000
Software	$ 5,100,000	2,700,000
Real estate leases option to renew description	Many of our real estate leases include one or more options to renew, with renewal terms that can extend the lease term from one to five years or more. To determine the expected lease term, we include any noncancelable periods within the lease agreement as well as any periods covered by an option to extend the lease if we are reasonably certain to exercise the option. The equipment leases do not typically include options for renewal but may include options for purchase at the end of the lease. We determine the likelihood of exercising the option for purchase by assessing the option price versus the estimated fair value at the end of the lease term to determine if the option price is advantageous enough that we are reasonably certain to exercise it. The depreciable life of finance lease assets and leasehold improvements are limited by the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise.
Lessee, Operating Lease, Existence of Option to Extend [true false]	true
Real estate leases option to extend lease term	one to five years or more
Foreign currency transaction (loss) gain	$ 4,500,000	(4,100,000)	(2,000,000)
Ryerson Credit Facility [Member]
Summary Of Accounting And Financial Policies [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 1,300,000,000	$ 1,000,000,000
Revolving credit facility maximum borrowing capacity				$ 1,300,000,000	$ 1,000,000,000
Shipping and Handling [Member]
Summary Of Accounting And Financial Policies [Line Items]
Shipping and handling costs	$ 144,000,000	$ 138,400,000	$ 139,100,000
Minimum [Member]
Summary Of Accounting And Financial Policies [Line Items]
Consolidates entities voting shares percentage	50.00%
Minimum [Member] \| Investments in Affiliates [Member]
Summary Of Accounting And Financial Policies [Line Items]
Investment in affliates, ownership percentage.	20.00%
Maximum [Member] \| Investments in Affiliates [Member]
Summary Of Accounting And Financial Policies [Line Items]
Investment in affliates, ownership percentage.	50.00%

Ryerson Holding Corp 10-K