Weighted Average Rates used to Determine Net Periodic Pension Expense (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2018
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components			$ 1
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation			$ 2
Foreign Plan [Member] \| Pension Plan [Member]
Discount rate	1.30%	1.90%	1.20%	1.90%
Rate of increase in future compensation levels	3.40%	2.30%	3.40%	2.40%
Expected long-term rate of return on plan assets	2.60%	3.10%	3.10%	3.10%
Foreign Plan [Member] \| Other Postretirement Benefits Plan [Member]
Discount rate	6.90%	6.30%	5.20%	5.30%
Rate of increase in future compensation levels	0.00%	0.00%	0.00%	0.00%
Expected long-term rate of return on plan assets	0.00%	0.00%	0.00%	0.00%
UNITED STATES \| Pension Plan [Member]
Discount rate	3.30%	4.10%	3.10%	3.50%
Rate of increase in future compensation levels	0.00%	0.00%	0.00%	0.00%
Expected long-term rate of return on plan assets	6.60%	6.60%	6.60%	6.70%
UNITED STATES \| Other Postretirement Benefits Plan [Member]
Discount rate	0.00%	4.10%	0.00%	3.20%
Rate of increase in future compensation levels	0.00%	0.00%	0.00%	0.00%
Expected long-term rate of return on plan assets	0.00%	0.00%	0.00%	0.00%

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://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

+ Details

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- Definition

Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- Definition

Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate.

+ References

+ Details

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