Financing - Schedule of Temporary Equity (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Temporary Equity [Line Items]
Redeemable preferred stock	$ 324	$ 324
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	324
Redeemed	(33)	(658)	$ 0
Issuance costs		(6)
Ending balance	291	324
Redeemable Preferred Stock
Temporary Equity [Line Items]
Redeemable preferred stock	324	118	118
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	324	118	118
Issued		250
Redeemed	(33)	(38)
Ending balance	$ 291	$ 324	$ 118

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

The cash outflow to reacquire preferred stock during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

+ Details

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- Definition

Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ 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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- Definition

Amount of increase (decrease) in temporary equity from changes classified as other.

+ References

No definition available.

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- Definition

Value of new stock classified as temporary equity issued during the period.

+ References

No definition available.

+ Details

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