Operations and summary of significant accounting policies (Details 2) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Variable Interest Entity [Line Items]
Receivables - trade and other	$ 5,981	$ 6,695
Receivables - finance	8,522	8,991
Long-term receivables - finance	13,556	13,651
Investments in unconsolidated affiliated companies	249	246
Guarantees	1,856	681
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Receivables - trade and other	55	19
Receivables - finance	174	466
Long-term receivables - finance	246	62
Investments in unconsolidated affiliated companies	31	35
Guarantees	210	175
Total	$ 716	$ 757

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.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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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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