Benefit Plans (Assumed long-term healthcare cost trend rate) (Details)	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Postemployment Benefits [Abstract]
Healthcare cost trend rate medical	7.50%	7.00%	7.00%
Healthcare prescription drug	7.50%	7.00%	7.00%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	4.50%	4.50%	4.50%

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

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

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant