Equity and Noncontrolling Interests - Redeemable Noncontrolling Interest (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 16	$ 11
Net income	1	1
Distributions to noncontrolling interest and other	(1)	(1)
Redemption value adjustments/accretion	0	2
Ending balance	$ 15	$ 13

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
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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

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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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.

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