Guarantees and Product Warranty (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Related liability	$ 5	$ 5
Guarantor Obligations
Guarantees, maximum potential amount of future payments	1,403	1,485
SPC assets in consolidated statement	80,784	78,324
SPC liabilities in consolidated statement	64,089	62,946
Caterpillar dealer performance guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	908	993
Supplier consortium performance guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	247	258
Other guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	248	234
Variable Interest Entity, Primary Beneficiary
Guarantor Obligations
SPC assets in consolidated statement	899	1,026
SPC liabilities in consolidated statement	$ 899	$ 1,025

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 current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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