Represents the percentage actual rate of return on asset under defined benefit plan.

No definition available.

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Rate of Return on Plan Assets

+ References

No definition available.

+ Details

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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

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.

+ References

No definition available.

+ Details

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RETIREMENT BENEFITS - Discount Rate and Expected Rate of Return (Details)	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension and Postretirement Plan \| U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans
Expected rate of return at period end (as a percent)		6.70%	5.80%	6.70%	6.70%
Expected return on assets during period (as a percent)	6.80%	6.70%	6.70%	6.70%
Actual rate of return (as a percent)			12.84%	15.20%	(3.40%)
VEBA Trust
Defined Benefit Plans and Other Postretirement Benefit Plans
Expected return on assets during period (as a percent)			3.00%	3.00%	3.00%
VEBA Trust \| U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans
Expected return on assets during period (as a percent)			3.00%	3.00%	3.00%
Actual rate of return (as a percent)			2.11%
Minimum \| VEBA Trust \| U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans
Actual rate of return (as a percent)				1.91%	0.43%
Maximum \| VEBA Trust \| U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans
Actual rate of return (as a percent)				2.76%	1.41%