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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Tax Credit Carryforward [Line Items] |  |  |  |
Federal statutory income tax rate | 21.00% | 35.00% |  |
Income tax benefit related to revaluation of net deferred tax liability |  | $ 242 |  |
Effective income tax rate | 153.70% | 39.80% |  |
Unrecognized tax benefit | $ 98 | $ 132 | $ 78 | $ 46
Decrease in unrecognized tax benefits from settlements of foreign jurisdiction audit | 69 |  | 3 |
Increase in unrecognized tax position from completion of audits of foreign jurisdictions from prior years | 31 | 64 | 65 |
Decrease in unrecognized tax benefits is reasonably possible | 7 |  |  |
Income tax interest and penalties related to unrecognized tax benefit | 0 | 17 | $ 10 |
Accrued income tax interest and penalties related to unrecognized tax benefit | 12 | $ 32 |  |
Foreign tax credit | 766 |  |  |
Net operating loss carry forward | 893 |  |  |
Tax-deductible goodwill | 133 |  |  |
Undistributed earnings of foreign subsidiaries | $ 3,254 |  |  |
Maximum [Member] |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Period of amortization of goodwill | 12 years |  |  |
Carry Forward Expiration Year 2020 [Member] |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Net operating loss carry forward | $ 10 |  |  |
Carry Forward Expiration Year 2022 [Member] |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Net operating loss carry forward | 141 |  |  |
Carry Forward Expiration Year 2026 [Member] |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Net operating loss carry forward | 286 |  |  |
Carry Forward Expiration Year 2027 [Member] |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Net operating loss carry forward | 142 |  |  |
Carry Forward Expiration Year 2028 [Member] |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Net operating loss carry forward | $ 187 |  |  |

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- Definition The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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- Definition Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
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