Ecovyst, Inc. Annual report [Section 13 and 15(d), not S-K Item 405]

Annual report [Section 13 and 15(d), not S-K Item 405]

Benefit Plans - Projected and Accumulated Benefit Obligation (Details)

Benefit Plans - Projected and Accumulated Benefit Obligation (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 17,791	$ 18,305
Accumulated benefit obligation	17,791	18,305
Fair value of plan assets	16,454	16,183
Other Postretirement Benefit Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	488	463
Accumulated benefit obligation	0	0
Fair value of plan assets	$ 0	$ 0

- 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.

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+ Details