Property, Plant and Equipment - Additional Information (Detail) £ in Thousands	1 Months Ended		12 Months Ended
	Jun. 30, 2023 USD ($)	Aug. 31, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 GBP (£)	Oct. 31, 2022	Oct. 14, 2022
Property Plant And Equipment [Line Items]
Remaining lease term			20 years			20 years	20 years	20 years
Estimated cost on upgrading existing equipment					$ 26,000,000
Finance lease assets gross value			$ 4,223,000	$ 3,917,000
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]			Long-Term Debt and Lease Obligation, Current	Long-Term Debt and Lease Obligation, Current		Long-Term Debt and Lease Obligation, Current
Finance lease, lease related accumulated amortization			$ 1,959,000	$ 1,577,000
Depreciation expense			17,317,000	17,040,000
Depreciation on assets under finance leases			333,000	496,000
Impairment of long lived assets			0
Interest capitalized on strategic capital projects			1,522,000	$ 435,000
Union Electric Steel UK Limited [Member]
Property Plant And Equipment [Line Items]
Land and buildings held as collateral			2,701,000			£ 2,122
Union Electric Steel UK Limited [Member] | Construction-in-Process, Machinery and Equipment or Buildings [Member]
Property Plant And Equipment [Line Items]
Machinery and equipment purchased			16,719,000
Capital Expenditures [Member]
Property Plant And Equipment [Line Items]
Proceeds from disbursement agreement	$ 2,500,000		2,500,000
Estimated cost on upgrading existing equipment		$ 2,500,000	$ 26,000,000