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Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Allowance for Doubtful Accounts [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | $ 161 | $ 187 | $ 209
Additions (Deductions) charged to costs and expenses | 21 | 17 | 6
Charge off's and other | (50) | (43) | (28)
Balance end of year | 132 | 161 | 187
Reserve for Excess and Obsolete Inventories [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 644 | 800 | 1,017
Additions (Deductions) charged to costs and expenses | 659 | 49 | 114
Charge off's and other | (460) | (205) | (331)
Balance end of year | 843 | 644 | 800
Valuation Allowance for Deferred Tax Assets [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 955 | 1,202 | 544
Additions (Deductions) charged to costs and expenses | 218 | 49 | 280
Charge off's and other | 2 | (296) | 378
Balance end of year | 1,175 | 955 | 1,202
Environmental Accruals [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 66 | 38 | 43
Additions (Deductions) charged to costs and expenses | 57 | 37 | 2
Charge off's and other | (19) | (9) | (7)
Balance end of year | 104 | 66 | 38
Warranty Reserve [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 105 | 135 | 172
Additions (Deductions) charged to costs and expenses | 41 | 38 | 46
Charge off's and other | (56) | (68) | (83)
Balance end of year | $ 90 | $ 105 | $ 135

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