Goodwill and Intangible Assets, Net - Definite-lived and Indefinite-lived Intangible Assets Table (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Definite-lived intangible assets: [Abstract]
Gross carrying amount of definite-lived intangible assets	$ 670		$ 670		$ 671
Accumulated amortization of definite-lived intangible assets	(332)		(332)		(302)
Net carrying amount of definite-lived intangible assets	338		338		369
Net carrying amount of indefinite-lived intangible assets	62		62		62
Intangible assets, net	400		400		431
Amortization of intangible assets	10	$ 10	31	$ 31
WPH
Definite-lived intangible assets: [Abstract]
Impairment of goodwill	3
Customer relationships
Definite-lived intangible assets: [Abstract]
Gross carrying amount of definite-lived intangible assets	397		397		397
Accumulated amortization of definite-lived intangible assets	(170)		(170)		(155)
Net carrying amount of definite-lived intangible assets	227		227		242
Other
Definite-lived intangible assets: [Abstract]
Gross carrying amount of definite-lived intangible assets	273		273		274
Accumulated amortization of definite-lived intangible assets	(162)		(162)		(147)
Net carrying amount of definite-lived intangible assets	$ 111		$ 111		$ 127

Finite-Lived Intangible Assets, Gross and Net [Abstract]

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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