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.

No definition available.

+ Details

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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- Details

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Postretirement Benefit Plans (Target and Actual Allocation Percentages) (Details)	Mar. 31, 2025	Mar. 31, 2024
Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation in aggregate	29.00%	29.00%
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation in aggregate	53.00%	53.00%
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation in aggregate	7.00%	7.00%
Other [Member]
Defined Benefit Plan Disclosure [Line Items]
Allocation in aggregate	11.00%	11.00%
Minimum \| Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	10.00%
Minimum \| Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	15.00%
Minimum \| Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	3.00%
Minimum \| Other [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	1.00%
Maximum \| Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	50.00%
Maximum \| Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	89.00%
Maximum \| Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	25.00%
Maximum \| Other [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Ranges	100.00%