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Affiliate Equity - Schedule of the Changes in Redeemable Non-controlling Interests (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Changes in redeemable non-controlling interests during the period
Beginning balance	$ 645.5	$ 641.9
Repurchases of redeemable Affiliate equity	(161.3)	(61.7)
Transfers from Non-controlling interests	49.5	22.7	$ 19.5
Changes in redemption value	81.6	43.0
Decrease attributable to consolidated products	(2.8)	(0.4)
Ending balance	$ 612.5	$ 645.5	$ 641.9

X

- Definition

Noncontrolling Interest, Decrease from Transfers to Noncontrolling Interest Holders

+ References

No definition available.

+ Details

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- Definition

Noncontrolling Interest, Increase (decrease) Attributable to Consolidated Partnerships

+ References

No definition available.

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X

- Definition

Increase (decrease) in redeemable non-controlling interests during the period as a result of a change in the redemption value.

+ References

No definition available.

+ Details

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- Definition

-- None. No documentation exists for this element. --

+ References

No definition available.

+ Details

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X

- Definition

The cash outflow during the period for redemption of redeemable noncontrolling interests.

+ References

No definition available.

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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (12)(c)
-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (16)(c)
-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 15
-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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