Ecovyst, Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Cover
- Cover
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Benefit Plans - Weighted Average Assumptions for Net Periodic Cost (Details)

v3.20.4

Benefit Plans - Weighted Average Assumptions for Net Periodic Cost (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Pension Plans \| United States
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost
Discount rate	3.32%	4.32%	3.74%
Rate of compensation increase	3.00%	3.00%	3.00%
Expected return on assets	5.55%	6.00%	6.00%
Defined Benefit Pension Plans \| Foreign
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost
Discount rate	2.34%	3.19%	3.11%
Rate of compensation increase	2.07%	2.08%	2.22%
Expected return on assets	2.82%	3.30%	3.37%
Supplemental Retirement Plans
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost
Discount rate	3.10%	4.20%	3.60%
Other Postretirement Benefits Plans
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost
Discount rate	3.06%	4.09%	3.53%

- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2919-114920

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- Definition

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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- References

No definition available.

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