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

Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details
Uncategorized

Benefit Plans - Weighted Average Assumptions for Pension Obligation (Details)

v3.8.0.1

Benefit Plans - Weighted Average Assumptions for Pension Obligation (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Immediate trend rate	6.20%	6.84%
Ultimate trend rate	4.50%	4.50%
Year that the rate reaches ultimate trend rate	2037	2035
Defined Benefit Pension Plans \| U.S.
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	3.74%	4.24%
Rate of compensation increase	3.00%	3.00%
Defined Benefit Pension Plans \| U.S. \| Eco Services Hourly Pension Plan
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Rate of compensation increase	3.00%	3.00%
Defined Benefit Pension Plans \| Foreign
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	2.91%	2.99%
Rate of compensation increase	2.57%	2.97%
Supplemental Retirement Plans
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	3.60%	3.90%
Other Postretirement Benefits Plans
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation
Discount rate	3.53%	3.74%

- Definition

Defined Benefit Plan Benefit Obligation, Health Care Cost Trend Rate Assumed, Next Fiscal Year

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate, Benefit Obligation

+ References

No definition available.

+ Details

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- 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- References

No definition available.

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- Details

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