SUPPLEMENTARY FINANCIAL INFORMATION (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Valuation allowance for deferred income taxes
Movement in valuation and qualifying accounts
Beginning Balance	$ 121.9	$ 95.7	$ 86.9
Additions	218.5	27.9	11.5
Deductions	(2.2)	(1.7)	(2.7)
Other	0.0	0.0	0.0
Ending Balance	338.2	121.9	95.7
Allowance for doubtful accounts
Movement in valuation and qualifying accounts
Beginning Balance	0.4	0.4	0.4
Additions	0.0	0.0	0.0
Deductions	0.0	0.0	0.0
Other	0.9	0.0	0.0
Ending Balance	$ 1.3	$ 0.4	$ 0.4

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of increase (decrease) in valuation and qualifying accounts and reserves from adjustment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column B))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column E))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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Amount of decrease in valuation and qualifying accounts and reserves.

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