Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Income Taxes [Abstract]
Unrecognized tax benefits that would impact effective tax rate if recognized	$ 13		$ 14
Unrecognized tax benefits, reasonably possible decrease within the next 12 months	$ 2
Effective tax rate on income from continuing operations (as a percent)	227.30%	5.50%

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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-Name Accounting Standards Codification
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