Basis of Presentation and Significant Accounting Policies Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Intangible assets	$ 362	$ 409
Goodwill, Impaired, Accumulated Impairment Loss	0
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	0
Impairment of Intangible Assets, Finite-lived	0
PWIC
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	$ 9

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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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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