PENSION AND POSTRETIREMENT EMPLOYEE BENEFIT PLANS - Weighted-average assumptions used to determine net periodic benefit costs and benefit obligations (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Benefit Plans \| United States
For Determining Net Periodic (Benefit) Cost
Discount rate	3.16%	4.25%	3.56%
Expected rate of return on plan assets	6.25%	7.25%	7.50%
Rate of compensation increase	0.00%	0.00%	0.00%
Interest crediting rate	5.00%	5.00%	5.00%
For Determining Benefit Obligation
Discount rate	2.25%	3.16%
Rate of compensation increase	0.00%	0.00%
Interest crediting rate	4.75%	5.00%
Pension Benefit Plans \| Foreign Plan
For Determining Net Periodic (Benefit) Cost
Discount rate	1.68%	2.39%	2.29%
Expected rate of return on plan assets	2.98%	3.46%	3.66%
Rate of compensation increase	3.05%	2.89%	2.87%
Interest crediting rate	0.00%	0.00%	0.00%
For Determining Benefit Obligation
Discount rate	1.37%	1.68%
Rate of compensation increase	2.60%	3.05%
Interest crediting rate	0.00%	0.00%
U.S. Postretirement Benefit Plan
For Determining Net Periodic (Benefit) Cost
Discount rate	3.04%	4.16%	3.47%
Expected rate of return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	0.00%	0.00%	0.00%
For Determining Benefit Obligation
Discount rate	2.09%	3.04%
Rate of compensation increase	0.00%	0.00%

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

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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 interest crediting rate used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate.

+ References

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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://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

Weighted-average interest crediting rate used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate.

+ References

+ Details

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