Investments in Unconsolidated Affiliated Companies (Details) - USD ($) $ in Millions	1 Months Ended
Feb. 28, 2015	Sep. 30, 2016	Dec. 31, 2015
Caterpillar's investments in unconsolidated affiliated companies:
Investments in equity method companies		$ 192	$ 203
Plus: Investments in cost method companies		55	43
Total investments in unconsolidated affiliated companies		$ 247	$ 246
Third party logistics business, investment
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest sold	35.00%
Sale price of investment	$ 177
Cash proceeds from sale	167
Note receivable from sale	10
Realized gain on disposal	120
Carrying value of noncontrolling interest	$ 57

This item represents the amount of cash proceeds received on disposal of an equity method investment.

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This item represents the note receivable received on disposal of an equity method investment.

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Percent of the reporting entity's equity method investment which has been sold.

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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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Amount of gain (loss) on sale or disposal of an equity method investment.

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Amount of equity attributable to noncontrolling interests of an equity method investment of the entity.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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