Pension, Post-Retirement and Post-Employment Plans - Key Assumptions Used to Determine Benefit Obligations (Details)	Dec. 31, 2020	Dec. 31, 2019
Pension and SERP Benefits \| Domestic
Defined Benefit Plans and Other Postretirement Benefit Plans
Discount rate	2.50%	3.30%
Rate of compensation increase	3.00%	3.50%
Interest crediting rate	5.30%	5.30%
Pension and SERP Benefits \| Foreign
Defined Benefit Plans and Other Postretirement Benefit Plans
Discount rate	0.70%	1.00%
Rate of compensation increase	2.70%	3.10%
Interest crediting rate	2.70%	2.60%
Post-retirement Medical Benefits \| Domestic
Defined Benefit Plans and Other Postretirement Benefit Plans
Discount rate	2.50%	3.20%
Post-retirement Medical Benefits \| Foreign
Defined Benefit Plans and Other Postretirement Benefit Plans
Discount rate	7.20%	7.30%

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

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

Weighted-average interest crediting rate used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate.

+ 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)(4)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- 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.

+ References

No definition available.

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