Guarantees and Product Warranty (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Related liability	$ 8	$ 8
Guarantor Obligations
Guarantees, maximum potential amount of future payments	2,152	2,105
Special-Purpose Corporation assets in Consolidated Statement of Financial Position	1,133	1,107
Special-Purpose Corporation liabilities in Consolidated Statement of Financial Position	1,133	1,106
Caterpillar dealer performance guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	1,375	1,313
Customer loan guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	31	40
Supplier consortium performance guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	556	565
Third party logistics business lease guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	68	69
Other guarantees
Guarantor Obligations
Guarantees, maximum potential amount of future payments	$ 122	$ 118

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

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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.

+ References

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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