Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Valuation allowance	$ (1)	$ 52
Undistributed earnings of certain foreign subsidiaries	5,730
Income taxes paid, net	484	665
Income tax loss carryforwards	2,430
Tax credit carryforwards	70
Total losses	1,670
Gross unrecognized tax benefits	192	198	$ 243
Recognized tax benefits	174	183
Interest and penalties on the unrecognized tax benefits	46	39
Recoveries/(expenses) related to changes in reserves for interest and penalties	(7)	$ (6)
Decrease in gross unrecognized tax benefits	32
Decrease in recognized tax benefits	$ 24
Minimum [Member]
Income Taxes [Line Items]
Expiry date of losses	2020
Maximum [Member]
Income Taxes [Line Items]
Expiry date of losses	2039

Income Taxes [Line Items]

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Net Operating Losses Expiration Year

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Significant change in unrecognized tax benefits reasonably possible amount of unrecorded benefit that would impact effective tax rate.

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Unrecognized tax benefits income tax recovery related to changes in penalties and interest.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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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.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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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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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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

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