Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Jan. 26, 2018
Equity [Abstract]
Share repurchase authorization			10.0
Treasury shares repurchased (in shares)	0.5
Treasury shares repurchased (in usd)	$ 24.5	$ 9.2
Share repurchase authorization, remaining	9.2
Dividends declared (per share)	$ 0.15
Dividends declared	$ 8.4
Dividends to common shareholders	$ (8.5)	$ 0.0

Aggregate dividends declared during the period for each share of common stock outstanding.

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

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-Publisher FASB
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- References

No definition available.

+ Details

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- Definition

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

+ References

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-Publisher FASB
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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

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