Schedule II - Valuation and Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance beginning of year	$ 132	$ 120	$ 107
Additions (Deductions) charged to costs and expenses	31	32	6
Charge off's and other	(38)	(20)	7
Balance end of year	125	132	120
Allowance for Excess and Obsolete Inventories [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance beginning of year	396	338	281
Additions (Deductions) charged to costs and expenses	128	89	99
Charge off's and other	(154)	(31)	(42)
Balance end of year	370	396	338
Valuation Allowance for Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance beginning of year	133	93	13
Additions (Deductions) charged to costs and expenses	(83)	40	80
Charge off's and other	(2)
Balance end of year	48	133	93
Warranty Reserve [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance beginning of year	228	194	211
Additions (Deductions) charged to costs and expenses	123	101	51
Charge off's and other	(79)	(67)	(68)
Balance end of year	$ 272	$ 228	$ 194

Valuation allowances and reserves charge offs and other accounts.

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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 FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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