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Affiliate Equity - Changes in the Company's Interest in its Affiliates on the Controlling Interest's Equity (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Affiliate Equity [Abstract]
Net income (controlling interest)	$ 212.4	$ 123.6	$ 369.0	$ 349.5
Decrease in controlling interest paid-in capital from Affiliate equity issuances	(4.4)	0.0	(4.1)	(2.6)
Decrease in controlling interest paid-in capital from Affiliate equity purchases	(45.1)	(0.5)	(36.5)	(22.9)
Net income (controlling interest) including the net impact of Affiliate equity transactions	$ 162.9	$ 123.1	$ 328.4	$ 324.0

X

- Definition

Adjustments to Additional Paid in Capital Increase (Decrease) in Carrying Amount of Redeemable Noncontrolling Interests, Issuances

+ References

No definition available.

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X

- Definition

The increase (decrease) in additional paid-in capital of the reporting entity from purchases and sales of Affiliate equity.

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- Definition

Affiliate Equity [Abstract]

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- Definition

Increase (decrease) in equity during the period due to net income attributable to the parent company and net transfers with non-controlling interests.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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