Pension and Postretirement Plans (Summary of Weighted-Average Assumptions) (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Pension Benefits \| United States
Assumptions Used to Determine Benefit Obligations:
Discount rate	3.30%	4.30%
Rate of compensation increase	4.00%	4.00%
Interest crediting rate on cash balance plan	2.70%	3.25%
Assumptions Used to Determine Net Periodic Benefit Cost:
Discount rate	4.30%	3.60%
Expected return on plan assets	6.50%	6.50%
Rate of compensation increase	4.00%	4.00%
Interest crediting rate on cash balance plan	3.25%	3.00%
Pension Benefits \| Int’l.
Assumptions Used to Determine Benefit Obligations:
Discount rate	1.81%	2.59%
Rate of compensation increase	3.34%	3.34%
Interest crediting rate on cash balance plan	0.00%	0.00%
Assumptions Used to Determine Net Periodic Benefit Cost:
Discount rate	2.59%	2.36%
Expected return on plan assets	4.93%	4.78%
Rate of compensation increase	3.34%	3.74%
Interest crediting rate on cash balance plan	0.00%	0.00%
Other Benefits
Assumptions Used to Determine Benefit Obligations:
Discount rate	3.05%	4.15%
Assumptions Used to Determine Net Periodic Benefit Cost:
Discount rate	4.15%	3.35%
Expected return on plan assets	0.00%	0.00%
Interest crediting rate on cash balance plan	0.00%	0.00%

Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Interest Crediting Rate, Cash Balance

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Interest Crediting Rate, Cash Balance

+ References

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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.

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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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