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Redeemable Non-Controlling Interests (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Redeemable Noncontrolling Interest [Roll Forward]
Balance, as of December 31, 2017	$ 811.9
Changes attributable to consolidated products	1.9
Transfers to Other liabilities	(45.6)
Transfers from Non-controlling interests	4.9	$ 25.7
Changes in redemption value	168.5
Balance, as of March 31, 2018	$ 941.6
Minimum
Noncontrolling Interest [Line Items]
Term of conditional right to put interest	5 years
Maximum
Noncontrolling Interest [Line Items]
Term of conditional right to put interest	15 years

X

- Definition

Noncontrolling Interest, Decrease from Transfers to Noncontrolling Interest Holders

+ References

No definition available.

+ Details

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X

- Definition

Noncontrolling Interest, Decrease from Transfers to Other Liabilities

+ References

No definition available.

+ Details

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- Definition

Noncontrolling Interest, Increase (decrease) Attributable to Consolidated Partnerships

+ References

No definition available.

+ Details

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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

Term Of Conditional Right to Put Interest

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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X

- 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=65877616&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=65877616&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=65877616&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=65877616&loc=SL6540498-122764

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