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Income Taxes - Summary of Net Operating Loss Carryforwards (Detail) $ in Millions	Dec. 31, 2019 USD ($)
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	$ 1,213
Tax Effected NOL	270
Valuation Allowance (VA)	(269)
Tax Effected NOL Net of VA	1
Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	234
Tax Effected NOL	49
Valuation Allowance (VA)	(49)
State [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	154
Tax Effected NOL	9
Valuation Allowance (VA)	(9)
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	825
Tax Effected NOL	212
Valuation Allowance (VA)	(211)
Tax Effected NOL Net of VA	1
2020 - 2024 Expiration [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	83
2020 - 2024 Expiration [Member] | Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	6
2020 - 2024 Expiration [Member] | State [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	4
2020 - 2024 Expiration [Member] | Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	73
2025 - 2039 Expiration [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	526
2025 - 2039 Expiration [Member] | Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	30
2025 - 2039 Expiration [Member] | State [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	150
2025 - 2039 Expiration [Member] | Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	346
Unlimited Expiration [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	604
Unlimited Expiration [Member] | Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	198
Unlimited Expiration [Member] | Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	$ 406

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Operating loss carryforward tax effected.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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