Pension and Other Post-Retirement Benefits - Assumptions (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Multiemployer Plans, Certified Zone Status [Fixed List]	Green
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	2.88%	4.06%
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	3.19%	4.32%
UNITED STATES \| Salaried Funded Plans [Member] [Domain]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	3.17%	4.32%
UNITED STATES \| Hourly Funded Plans [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	3.35%	4.42%
Discount rate, net periodic cost (benefit)	4.43%	3.74%
Expected return on plan assets, net periodic cost (benefit)	6.00%	5.50%
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)	4.32%	3.68%
Expected return on plan assets, net periodic cost (benefit)	6.20%	5.90%
Rate of compensation and pension-in-payment increases, net periodic cost (benefit)	3.00%	2.50%
Foreign Plan [Member]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	1.90%	2.60%
Rate of compensation and pension-in-payment increases, benefit obligation	3.00%	3.20%
Discount rate, net periodic cost (benefit)	2.60%	2.40%
Expected return on plan assets, net periodic cost (benefit)	4.00%	4.10%
Rate of compensation and pension-in-payment increases, net periodic cost (benefit)	3.20%	3.10%
Minimum [Member] \| UNITED STATES \| Salaried Unfunded Plans [Domain]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	0.00%	0.00%
Maximum [Member] \| UNITED STATES \| Salaried Unfunded Plans [Domain]
Expected long term return on assets and to measure the periodic cost
Discount rate, benefit obligation	0.00%	0.00%
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)	4.05%	3.41%
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)	4.32%	3.66%

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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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://fasb.org/us-gaap/role/ref/legacyRef
-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 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://fasb.org/us-gaap/role/ref/legacyRef
-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

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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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.

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- Definition

Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

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