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Schedule II - Valuation and Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Allowance for Doubtful Accounts [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | $ 107 | $ 107 | $ 95
Additions (Deductions) charged to costs and expenses | 6 | 9 | 39
Charge off's and other | 7 | (9) | (27)
Balance end of year | 120 | 107 | 107
Allowance for excess and obsolete inventories [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 281 | 270 | 206
Additions (Deductions) charged to costs and expenses | 99 | 70 | 106
Charge off's and other | (42) | (59) | (42)
Balance end of year | 338 | 281 | 270
Valuation allowance for deferred tax assets [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 13 | 9 | 8
Additions (Deductions) charged to costs and expenses | 80 | 4 | 1
Charge off's and other |  |  |
Balance end of year | 93 | 13 | 9
Warranty reserve [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance beginning of year | 211 | 215 | 217
Additions (Deductions) charged to costs and expenses | 51 | 40 | 52
Charge off's and other | (68) | (44) | (54)
Balance end of year | $ 194 | $ 211 | $ 215

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- Definition Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 09 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690 + Details
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