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Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Smith, Gambrell & Russell, LLP [Member]
Related Party Transaction [Line Items]
Fees payable to Smith, Gambrell & Russell	$ 0.2	$ 0.1
European Metal Recycling Limited [Member]
Related Party Transaction [Line Items]
Tendering process to select best buyer of scrap metal	0.1	0.1
Advan Six [Member]
Related Party Transaction [Line Items]
Tendering process to select best buyer of scrap metal	0.2	$ 0.3
Related Party [Member] \| Smith, Gambrell & Russell, LLP [Member]
Related Party Transaction [Line Items]
Amount due to related party	0.1		$ 0.0
Related Party [Member] \| European Metal Recycling Limited [Member]
Related Party Transaction [Line Items]
Amount due to related party	0.1		0.0
Related Party [Member] \| Advan Six [Member]
Related Party Transaction [Line Items]
Amount due to related party	$ 0.0		$ 0.0