Segment Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) group_presidents segments dealers	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information
Number of group presidents \| group_presidents	5
Number of operating segments \| segments	6
Useful life to amortize goodwill for segment assets	20 years
Reportable Segments
Sales and revenues	$ 12,859	$ 9,822
Depreciation and amortization	681	710
Consolidated profit before taxes	2,134	289
Segment assets	78,014		$ 76,962
Capital expenditures	757	509
Revenues earned from Machinery, Energy & Transportation	$ 105	86
All Other operating segments
Segment Reporting Information
Number of group presidents \| group_presidents	1
Number of smaller operating segments led by Group President \| group_presidents	2
Number of wholly-owned dealers involved in segment reallocation \| dealers	1
Reportable Segments
Sales and revenues		37
Depreciation and amortization	$ 57	54
Consolidated profit before taxes	57	(14)
Segment assets	1,342		1,312
Capital expenditures	11	20
Reportable Segments Including Intersegment Eliminations
Reportable Segments
Sales and revenues	$ 13,998	10,757
Reportable Segments
Segment Reporting Information
Number of operating segments led by Group Presidents \| segments	3
Number of operating segments led by Group President responsible for corporate services \| segments	1
Reportable Segments
Number of reportable segments \| segments	4
Sales and revenues	$ 12,936	9,877
Depreciation and amortization	566	595
Consolidated profit before taxes	2,510	1,522
Segment assets	54,584		53,698
Capital expenditures	588	429
Intersegment sales and revenues
Reportable Segments
Sales and revenues	1,062	880
Machinery, Energy & Transportation \| Reportable Segments Including Intersegment Eliminations
Reportable Segments
Sales and revenues	13,205	9,997
Machinery, Energy & Transportation \| Reportable Segments
Reportable Segments
Sales and revenues	12,143	9,117
Depreciation and amortization	363	387
Consolidated profit before taxes	2,369	1,339
Segment assets	19,252		18,805
Capital expenditures	227	158
Machinery, Energy & Transportation \| Intersegment sales and revenues
Reportable Segments
Sales and revenues	1,062	880
Construction Industries \| Reportable Segments Including Intersegment Eliminations
Reportable Segments
Sales and revenues	5,677	4,100
Construction Industries \| Reportable Segments
Reportable Segments
Sales and revenues	5,659	4,091
Depreciation and amortization	89	102
Consolidated profit before taxes	1,117	634
Segment assets	4,961		4,838
Capital expenditures	42	21
Construction Industries \| Intersegment sales and revenues
Reportable Segments
Sales and revenues	18	9
Resource Industries \| Reportable Segments Including Intersegment Eliminations
Reportable Segments
Sales and revenues	2,309	1,761
Resource Industries \| Reportable Segments
Reportable Segments
Sales and revenues	2,208	1,670
Depreciation and amortization	116	127
Consolidated profit before taxes	378	160
Segment assets	6,172		6,403
Capital expenditures	23	21
Resource Industries \| Intersegment sales and revenues
Reportable Segments
Sales and revenues	101	91
Energy & Transportation \| Reportable Segments Including Intersegment Eliminations
Reportable Segments
Sales and revenues	5,219	4,136
Energy & Transportation \| Reportable Segments
Reportable Segments
Sales and revenues	4,276	3,356
Depreciation and amortization	158	158
Consolidated profit before taxes	874	545
Segment assets	8,119		7,564
Capital expenditures	162	116
Energy & Transportation \| Intersegment sales and revenues
Reportable Segments
Sales and revenues	943	780
Financial Products Segment \| Reportable Segments Including Intersegment Eliminations
Reportable Segments
Sales and revenues	793	760
Financial Products Segment \| Reportable Segments
Reportable Segments
Sales and revenues	793	760
Depreciation and amortization	203	208
Consolidated profit before taxes	141	183
Segment assets	35,332		$ 34,893
Capital expenditures	361	271
Financial Products Segment \| Intersegment sales and revenues
Reportable Segments
Sales and revenues	$ 0	$ 0

The number of group presidents that comprise the reporting entity's executive office.

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Represents the number of operating segments that are led by the group president who is responsible for corporate services.

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Number of wholly-owned dealers moved from one operating segment to different operating segment.

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Amount of total capital expenditures attributable to the reportable segments.

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Represents the useful life used to amortize goodwill to allocate to segments assets.

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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.

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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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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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