Summary of Significant Accounting Policies (New Accounting Pronouncements) (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Adoption of New Accounting Standard Current Expected Credit Losses	$ 0	$ 14	$ 0
Accounting Standards Update 2016-13 [Member]
Adoption of New Accounting Standard Current Expected Credit Losses	$ 15

Adoption of New Accounting Standard Current Expected Credit Losses

No definition available.

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