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Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Allowance for Doubtful Accounts [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | $ 187 | $ 209 | $ 159
Additions (Deductions) charged to costs and expenses | 17 | 6 | 52
Charge off's and other | (43) | (28) | (2)
Balance end of year | 161 | 187 | 209
Reserve for Excess and Obsolete Inventories [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 800 | 1,017 | 500
Additions (Deductions) charged to costs and expenses | 49 | 114 | 606
Charge off's and other | (205) | (331) | (89)
Balance end of year | 644 | 800 | 1,017
Valuation Allowance for Deferred Tax Assets [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 1,202 | 544 | 63
Additions (Deductions) charged to costs and expenses | 49 | 280 | 476
Charge off's and other | (296) | 378 | 5
Balance end of year | 955 | 1,202 | 544
Warranty Reserve [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 135 | 172 | 244
Additions (Deductions) charged to costs and expenses | 38 | 46 | 50
Charge off's and other | (68) | (83) | (122)
Balance end of year | $ 105 | $ 135 | $ 172

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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