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 Pension Obligation (Details)

v3.20.4

Benefit Plans - Weighted Average Assumptions for Pension Obligation (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Pension Plans \| United States
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	2.42%	3.32%
Rate of compensation increase		3.00%
Defined Benefit Pension Plans \| Foreign
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	1.78%	2.34%
Rate of compensation increase	2.05%	2.07%
Supplemental Retirement Plans
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	2.20%	3.10%
Other Postretirement Benefits Plans
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	2.18%	3.06%
Immediate trend rate	5.67%	5.91%
Ultimate trend rate	4.38%	4.39%
Year that the rate reaches ultimate trend rate	2038	2038

- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation 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)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related 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)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement 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 (l)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- References

No definition available.

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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