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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, 2019	Mar. 31, 2018
Affiliate Equity [Abstract]
Net income (loss) (controlling interest)	$ (200.8)	$ 153.0
Decrease in controlling interest paid-in capital from Affiliate equity issuances	(0.7)	(1.0)
Decrease in controlling interest paid-in capital from Affiliate equity repurchases	(17.3)	(33.1)
Net income (loss) (controlling interest) including the net impact of Affiliate equity transactions	$ (218.8)	$ 118.9

X

- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Affiliate Equity [Abstract]

+ References

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X

- Definition

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

+ References

No definition available.

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X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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