Income Taxes - Income (Loss) Before Income Taxes (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income (Loss) Before Income Taxes - United States	$ (219)	$ (2,784)	$ (2,431)
Income (Loss) Before Income Taxes - Foreign	439	(2,994)	(1,423)
Income (Loss) Before Income Taxes	$ 220	$ (5,778)	$ (3,854)

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
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- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
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-Publisher FASB
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-Topic 944
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-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

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