Pension and Postretirement Benefit Plans and Defined Contribution Plans - Weighted-Average Actuarial Assumptions (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Postretirement Benefits Plan [Member]
Weighted-average assumptions used to determine benefit obligations:
Weighted-average assumptions used to determine benefit obligations, Discount rate	3.20%	4.30%	3.70%
Weighted-average assumptions used to determine net periodic benefit cost:
Weighted-average assumptions used to determine net periodic benefit cost, Discount rate	4.30%	3.70%	4.20%
Weighted-average assumptions used to determine net periodic benefit cost, Expected return on plan assets	7.30%	7.50%	8.00%
Foreign Plan [Member] \| Pension Plan [Member]
Weighted-average assumptions used to determine benefit obligations:
Weighted-average assumptions used to determine benefit obligations, Discount rate	1.70%	2.50%	2.30%
Weighted-average assumptions used to determine benefit obligations, Rate of compensation increase	1.40%	1.40%	2.50%
Weighted-average assumptions used to determine net periodic benefit cost:
Weighted-average assumptions used to determine interest cost, Discount rate	2.20%	2.00%	2.10%
Weighted-average assumptions used to determine service cost, Discount rate	2.40%	2.30%	2.30%
Weighted-average assumptions used to determine net periodic benefit cost, Expected return on plan assets	3.90%	4.40%	4.70%
Weighted-average assumptions used to determine net periodic benefit cost, Rate of compensation increase	1.40%	2.50%	2.60%
Qualified Plan [Member] \| United States [Member] \| Pension Plan [Member]
Weighted-average assumptions used to determine benefit obligations:
Weighted-average assumptions used to determine benefit obligations, Discount rate	3.30%	4.40%	3.80%
Weighted-average assumptions used to determine benefit obligations, Rate of compensation increase	0.00%	0.00%	2.80%
Weighted-average assumptions used to determine net periodic benefit cost:
Weighted-average assumptions used to determine net periodic benefit cost, Discount rate	4.40%	3.80%	4.30%
Weighted-average assumptions used to determine net periodic benefit cost, Expected return on plan assets	7.20%	7.50%	8.00%
Weighted-average assumptions used to determine net periodic benefit cost, Rate of compensation increase	0.00%	2.80%	2.80%
Nonqualified Plan [Member] \| United States [Member] \| U.S. Supplemental (Non-Qualified) Pension Plans [Member]
Weighted-average assumptions used to determine benefit obligations:
Weighted-average assumptions used to determine benefit obligations, Discount rate	3.20%	4.30%	3.70%
Weighted-average assumptions used to determine benefit obligations, Rate of compensation increase	0.00%	0.00%	2.80%
Weighted-average assumptions used to determine net periodic benefit cost:
Weighted-average assumptions used to determine net periodic benefit cost, Discount rate	4.30%	3.70%	4.20%
Weighted-average assumptions used to determine net periodic benefit cost, Rate of compensation increase	0.00%	2.80%	2.80%

Defined Benefit Plan, Assumptions Used Calculating Interest Cost, Discount Rate

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Service Cost, Discount Rate

+ References

No definition available.

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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://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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- 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://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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- 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

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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