Pension and Other Post-Retirement Benefits - Assumptions (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Retiree Health and Life [Member] \| Salaried and Hourly Health [Member] [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	1.93%	2.88%
Retiree Health and Life [Member] \| Salaried and Hourly Life Insurance [Member] [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	2.46%	3.19%
UNITED STATES \| Salaried Funded Plans [Member] [Domain]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	2.42%	3.17%
us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationCashBalance	3.09%	3.09%
UNITED STATES \| Hourly Funded Plans [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	2.73%	3.35%
Discount rate, net periodic cost (benefit)	3.35%	4.43%
Expected return on plan assets, net periodic cost (benefit)	5.30%	6.00%
UNITED STATES \| Salaried Funded and Unfunded Plans [Member]
Expected long term return on assets and to measure the periodic cost
Rate of compensation and pension-in-payment increases, benefit obligation	3.00%	3.00%
Discount rate, net periodic cost (benefit)	3.17%	4.32%
Expected return on plan assets, net periodic cost (benefit)	5.60%	6.20%
Rate of compensation and pension-in-payment increases, net periodic cost (benefit)	3.00%	3.00%
Foreign Plan [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	1.20%	1.90%
Rate of compensation and pension-in-payment increases, benefit obligation	2.90%	3.00%
Discount rate, net periodic cost (benefit)	1.90%	2.60%
Expected return on plan assets, net periodic cost (benefit)	3.60%	4.00%
Rate of compensation and pension-in-payment increases, net periodic cost (benefit)	3.00%	3.20%
Minimum [Member] \| UNITED STATES \| Salaried Unfunded Plans [Domain]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	1.19%	2.45%
Maximum [Member] \| UNITED STATES \| Salaried Unfunded Plans [Domain]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	2.35%	3.12%
Health Care [Member] \| Retiree Health and Life [Member] \| Salaried and Hourly Health [Member] [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, net periodic cost (benefit)	2.85%	4.05%
Postretirement Life Insurance [Member] \| Retiree Health and Life [Member] \| Salaried and Hourly Health [Member] [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, net periodic cost (benefit)	3.19%	4.32%

us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationCashBalance

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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

+ Details

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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

+ Details

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- 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

+ Details

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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.

+ References

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- References

No definition available.

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