Provision for Income Tax.

No definition available.

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- Definition

Unrecognized Tax Benefits, Portion Expected To Be Resolved in the Next Fiscal Year

+ References

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
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-Topic 740
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=116821951&loc=d3e32123-109318

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- Definition

Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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- Definition

Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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-Publisher FASB
-Name Accounting Standards Codification
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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Taxes (Textuals) [Abstract]
Effective tax rate (percent)	19.20%	24.70%	20.00%	40.60%
Unrecognized tax benefits from lapse of statute of limitations			$ 7
Unrecognized tax benefits decrease in period	$ 10
Unrecognized tax benefits, portion expected to be resolved in the next fiscal year	54		54
Unrecognized tax benefits that would impact effective tax rate	$ 51		$ 51
State and Local Jurisdiction \| West Virginia
Income Taxes (Textuals) [Abstract]
Re-measurement in state deferred taxes		$ 126