v3.19.3.a.u2

Income Taxes (Income Tax Contingencies) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Balance, beginning of period	$ (28)	$ (38)	$ (59)
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	0	7	0
Decreases related to prior year tax positions	0	17	11
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions	(1)	0	(2)
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	0	0	12
Balance, end of period	$ (29)	$ (28)	$ (38)

X

- Definition

Decreases Related to Change in Tax Rate of Net Deferred Tax Asset

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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