Redeemable Noncontrolling Interest (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Redeemable Noncontrolling Interest, Equity, Rollforwad [Roll Forward]
Beginning Balance	$ 304.3
Net Loss Attributable to Redeemable Noncontrolling Interest	(5.3)
Other Comprehensive Income, Net of Tax	8.4	$ 0.3
Redemption of IP's Ownership Interest	(250.0)	$ (6.7)
Redeemable Noncontrolling Interest Redemption Value Adjustment	(18.1)
Distributions of Membership Interest	(1.1)
Ending Balance	$ 38.2

Other Comprehensive Income (Loss), Net Of Tax, Portion Attributable To Redeemable Noncontrolling Interest

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- Definition

Redeemable Noncontrolling Interest, Equity

+ References

No definition available.

+ Details

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- Definition

Temporary Equity, Distributions Of Membership Interest

+ References

No definition available.

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- Definition

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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-Section S99
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 23
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
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-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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- Definition

The portion of net income or loss attributable to temporary equity interest.

+ References

No definition available.

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