v3.26.1

BASIS OF PRESENTATION (Details) $ in Millions		3 Months Ended
BASIS OF PRESENTATION (Details) $ in Millions	Mar. 19, 2026 Y	Mar. 31, 2026 USD ($) item D	Mar. 31, 2025 USD ($)	Apr. 10, 2026 USD ($)	Dec. 31, 2025 USD ($)
BASIS OF PRESENTATION
Liquidity amount		$ 114.2
Accumulated deficit		(1,455.2)			$ (1,339.3)
Used cash in operations		$ (232.9)	$ (110.2)
Restriction period for second lien enforcement	180	180
Number of new board members appointed \| item		2
Principal amount		$ 2,782.4			2,558.4
Super-Priority Revolver
BASIS OF PRESENTATION
Principal amount		$ 265.0			$ 75.0
Super-Priority Revolver \| Subsequent Event
BASIS OF PRESENTATION
Principal amount				$ 50.0

Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]

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Amount of which the company has ability to meet its shortterm financial obligations.

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Number of new board members appointed with significant experience in debt restructuring and strategic transactions.

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Trinseo PLC 10-Q