Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Undistributed earnings of certain foreign subsidiaries	$ 3,900
Income taxes paid, net	647	$ 527
Income tax loss carryforwards	1,920
Tax credit carryforwards	24
Total losses	$ 1,250
Expiry date of losses	Between 2016 and 2035
Gross unrecognized tax benefits	$ 221	202	$ 238
Recognized tax benefits	158	177
Interest and penalties on the unrecognized tax benefits	21	24
Recoveries/(expenses) related to changes in reserves for interest and penalties	3	$ 18
Decrease in gross unrecognized tax benefits	50
Decrease in recognized tax benefits	$ 49

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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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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 pertaining to uncertain tax positions taken in tax returns.

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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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