Nature of Operations, Basis of Presentation and Change in Accounting Principle (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Variable Interest Entity Maximum Exposure
Payments made for terminated contract with a related guarantee	$ 0
Receivables - trade and other	7,974	$ 7,370	$ 7,436
Receivables - finance	8,824		8,757
Long-term receivables - finance	13,244		13,542
Guarantees	2,152		2,105
Amount of deferred revenue reclassified from other current liabilities to customer advances			233
Variable Interest Entity
Variable Interest Entity Maximum Exposure
Receivables - trade and other	29		34
Receivables - finance	47		42
Long-term receivables - finance	26		38
Investments in unconsolidated affiliated companies	30		39
Guarantees	0		259
Total	$ 132		$ 412

Amount of deferred revenue reclassified from other current liabilities to customer advances

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Payments made for terminated contract with a related guarantee

+ References

No definition available.

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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-Publisher FASB
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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

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Amount of investment in equity method investee and investment in and advance to affiliate.

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An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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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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