Related Party Transactions - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Smith, Gambrell & Russell, LLP [Member]
Related Party Transaction [Line Items]
Fees incured from Smith, Gambrell & Russell		$ 200,000
European Metal Recycling Limited [Member]
Related Party Transaction [Line Items]
Other Liabilities	$ 0		$ 0
European Metal Recycling Limited [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Tendering process to select best buyer of scrap metal	100,000	100,000
Advan Six [Member]
Related Party Transaction [Line Items]
Other Liabilities	0		$ 0
Tendering process to select best buyer of scrap metal	$ 0	$ 0

Amount of liabilities classified as other.

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

INNOSPEC INC. 10-Q