Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Segment Y M D	Sep. 30, 2010	Dec. 31, 2010 Segment Y
Reportable Segments
Number of operating segments			7		25
Number of reportable segments			4		12
Number of operating segments led by Group Presidents			3
Number of operating segment led by Group president responsible for corporate services			1
Number of smaller operating segments led by Group President			3
Useful life of goodwill (in years)			20
External sales and revenues	$ 15,716	$ 11,134	$ 42,895	$ 29,781
Depreciation and amortization	658	565	1,832	1,681
Segment profit	1,759	1,187	5,193	2,672
Segment assets	77,767		77,767		64,020
Machinery and Power Systems
Reportable Segments
External sales and revenues	15,023	10,452	40,835	27,726
Depreciation and amortization	477	388	1,287	1,138
Segment assets	51,505		51,505		39,491
Machinery and Power Systems \| Reportable segments
Reportable Segments
External sales and revenues	14,574	9,924	39,327	26,202
Inter-segment sales and revenues	1,052	870	2,976	2,162
Total sales and revenues	15,626	10,794	42,303	28,364
Depreciation and amortization	424	325	1,078	945
Segment profit	2,035	1,478	6,089	3,259
Segment assets	30,509		30,509		19,140
Capital expenditures	672	284	1,287	701
Construction Industries \| Reportable segments
Reportable Segments
External sales and revenues	4,900	3,466	14,312	9,469
Inter-segment sales and revenues	162	179	433	481
Total sales and revenues	5,062	3,645	14,745	9,950
Depreciation and amortization	136	123	382	377
Segment profit	496	246	1,522	496
Segment assets	7,390		7,390		6,927
Capital expenditures	234	124	471	288
Resource Industries \| Reportable segments
Reportable Segments
External sales and revenues	4,599	2,262	10,573	5,860
Inter-segment sales and revenues	290	206	848	552
Total sales and revenues	4,889	2,468	11,421	6,412
Depreciation and amortization	155	70	298	210
Segment profit	745	538	2,337	1,183
Segment assets	14,903		14,903		3,892
Capital expenditures	159	68	320	139
Power Systems \| Reportable segments
Reportable Segments
External sales and revenues	5,075	4,196	14,442	10,873
Inter-segment sales and revenues	600	485	1,695	1,129
Total sales and revenues	5,675	4,681	16,137	12,002
Depreciation and amortization	133	132	398	358
Segment profit	794	694	2,230	1,580
Segment assets	8,216		8,216		8,321
Capital expenditures	279	92	496	274
Financial Products Segment \| Reportable segments
Reportable Segments
External sales and revenues	757	737	2,251	2,220
Total sales and revenues	757	737	2,251	2,220
Depreciation and amortization	177	175	535	538
Segment profit	145	108	453	324
Segment assets	31,116		31,116		30,346
Capital expenditures	311	290	830	677
Reportable segments
Reportable Segments
External sales and revenues	15,331	10,661	41,578	28,422
Inter-segment sales and revenues	1,052	870	2,976	2,162
Total sales and revenues	16,383	11,531	44,554	30,584
Depreciation and amortization	601	500	1,613	1,483
Segment profit	2,180	1,586	6,542	3,583
Segment assets	61,625		61,625		49,486
Capital expenditures	$ 983	$ 574	$ 2,117	$ 1,378

The overall number of the entity's operating segments for its business activity.

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The number of the entity's reportable segments, which are operating segments that meet the segment reporting criteria set forth in the related guidance and thus need to report separate information.

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Amount of total capital expenditures attributable to the reportable segments.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Statement of Financial Accounting Concepts (CON)

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-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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-Publisher FASB

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-SubTopic 10

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-Paragraph 28

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The useful life of all finite-lived intangible assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 12, 13, 14

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The net result for the period of deducting operating expenses from operating revenues.

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 225

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Amount of revenue from transactions with other operating segments of the same entity.

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Amount of total revenue for the reportable segments, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. All considered to be "operating revenue" for purposes of the taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 27

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-SubTopic 10

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-Paragraph 22

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