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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
	Mar. 31, 2022	Mar. 31, 2021
Affiliate Equity [Abstract]
Net income (controlling interest)	$ 146.0	$ 149.9
(Decrease) Increase in controlling interest paid-in capital from Affiliate equity issuances	3.4	(0.5)
Decrease in controlling interest paid-in capital from Affiliate equity purchases	(25.9)	(47.8)
Net income (controlling interest) including the net impact of Affiliate equity transactions	$ 123.5	$ 101.6

X

- Definition

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

+ References

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Adjustments to Additional Paid in Capital Decrease in Carrying Amount of Redeemable Noncontrolling Interests

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

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