Investments in Unconsolidated Affiliated Companies (Details) - USD ($) $ in Millions	May 01, 2017	Sep. 30, 2017	Dec. 31, 2016
Caterpillar's investments in unconsolidated affiliated companies:
Investments in equity method companies		$ 219	$ 192
Plus: Investments in cost method companies		33	57
Total investments in unconsolidated affiliated companies		$ 252	$ 249
Iron Planet Holdings, Inc. investment
Schedule of Equity Method Investments [Line Items]
Sale price of investment	$ 93
Realized gain on sale of investment	$ 85

The cash inflow associated with the sale of cost method investments.

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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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This item represents the gain (loss) realized during the period from the sale of investments accounted for under the cost method of accounting and any losses recognized thereon for impairments of other than a temporary nature.

+ References

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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.

+ References

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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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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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