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Income Taxes - Summary of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Income Tax Disclosure [Abstract] |  |
Tax benefit of loss carryforwards | $ 735 | $ 622
Operating lease liabilities | 469 | 452
Liabilities currently not deductible for tax | 259 | 234
Unrealized loss on foreign exchange hedges and retirement liabilities | 87 | 69
Tax credit carryforwards | 64 | 70
Others | 46 | 41
Deferred tax assets, Gross, Total | 1,660 | 1,488
Valuation allowance against tax benefit of loss carryforwards | (569) | (515)
Other valuation allowance | (206) | (170)
Deferred tax assets, Net, Total | 885 | 803
Operating lease right-of-use assets | 470 | 447
Tax depreciation in excess of book depreciation | 239 | 242
Tax on undistributed foreign earnings | 163 | 137
Other assets book value in excess of tax values | 65 | 66
Unrealized gain on foreign exchange hedges and retirement liabilities | 17 | 18
Unrealized gain on remeasurement of investments | 11 | 4
Deferred tax liabilities, Total | 965 | 914
Net deferred tax liabilities | $ (80) | $ (111)

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