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Income Taxes - Summary of Net Operating Loss Carryforwards (Detail) $ in Millions	Dec. 31, 2018 USD ($)
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	$ 893
Tax Effected NOL	182
Valuation Allowance (VA)	(154)
Tax Effected NOL Net of VA	28
Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	34
Tax Effected NOL	7
Valuation Allowance (VA)	(6)
Tax Effected NOL Net of VA	1
State [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	144
Tax Effected NOL	8
Valuation Allowance (VA)	(8)
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	715
Tax Effected NOL	167
Valuation Allowance (VA)	(140)
Tax Effected NOL Net of VA	27
2019 - 2021 Expiration [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	59
2019 - 2021 Expiration [Member] | Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	6
2019 - 2021 Expiration [Member] | State [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	2
2019 - 2021 Expiration [Member] | Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	51
2022 - 2033 Expiration [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	178
2022 - 2033 Expiration [Member] | Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	16
2022 - 2033 Expiration [Member] | State [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	20
2022 - 2033 Expiration [Member] | Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	142
2034 - 2038 Expiration [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	228
2034 - 2038 Expiration [Member] | Federal [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	12
2034 - 2038 Expiration [Member] | State [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	122
2034 - 2038 Expiration [Member] | Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	94
Unlimited Expiration [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	428
Unlimited Expiration [Member] | Foreign [Member]
Operating Loss Carryforwards [Line Items]
Total Net Operating Loss (NOL)	$ 428

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Operating loss carryforward tax effected.

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

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-Publisher FASB
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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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