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Valuation and Qualifying Accounts (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Allowance for Doubtful Accounts [Member] |  |  |
Valuation of Qualifying Accounts |  |  |
Balance beginning of year | $ 107 | $ 95 | $ 73
Additions (Deductions) charged to costs and expenses | 9 | 39 | 53
Charge off's and other | (9) | (27) | (31)
Balance end of year | 107 | 107 | 95
Allowance for excess and obsolete inventories [Member] |  |  |
Valuation of Qualifying Accounts |  |  |
Balance beginning of year | 270 | 206 | 123
Additions (Deductions) charged to costs and expenses | 70 | 106 | 100
Charge off's and other | (59) | (42) | (17)
Balance end of year | 281 | 270 | 206
Valuation allowance for deferred tax assets [Member] |  |  |
Valuation of Qualifying Accounts |  |  |
Balance beginning of year | 9 | 8 | 10
Additions (Deductions) charged to costs and expenses | 4 | 1 | 0
Charge off's and other | 0 | 0 | (2)
Balance end of year | 13 | 9 | 8
Warranty reserve [Member] |  |  |
Valuation of Qualifying Accounts |  |  |
Balance beginning of year | 215 | 217 | 114
Additions (Deductions) charged to costs and expenses | 40 | 52 | 144
Charge off's and other | (44) | (54) | (41)
Balance end of year | $ 211 | $ 215 | $ 217

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- Definition Valuation allowances and reserves charge offs and other accounts. + References No definition available. + Details
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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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- 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, charged to costs and expenses. + 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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