UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares shares in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Mar. 31, 2024	Sep. 30, 2024	Mar. 31, 2024	Mar. 31, 2023
Common stock, par value (in per share)	$ 0	$ 0	$ 0	$ 0
Common stock, shares authorized (in shares)	Unlimited	Unlimited	Unlimited	Unlimited
Common stock, shares issued (in shares)	253.4	288.7	253.4	253.4

Face amount per share of no-par value common stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Indicates whether number of common shares permitted to be issued is unlimited. Acceptable value is "Unlimited".

+ References

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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