Financing Receivables - Past Due (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Past Due Financing Receivable
Total Recorded Investment	$ 27,114	$ 30,877
Total Lease Receivable and Loan Receivable Portfolio Segments
Past Due Financing Receivable
Total Recorded Investment	17,747	19,259
Recorded Investment Not Accruing	359	331
Recorded investment, impaired financing receivables with related allowance	291	269
Impaired financing receivables, related allowance	250	250
Total Lease Receivable and Loan Receivable Portfolio Segments \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	853	825
Recorded Investment > 90 Days and Accruing	561	507
Billed Invoices > 90 Days and Accruing	70	77
Total Lease Receivable and Loan Receivable Portfolio Segments \| Americas
Past Due Financing Receivable
Total Recorded Investment	9,644	10,626
Total Lease Receivable and Loan Receivable Portfolio Segments \| EMEA
Past Due Financing Receivable
Total Recorded Investment	4,690	4,946
Total Lease Receivable and Loan Receivable Portfolio Segments \| Asia Pacific
Past Due Financing Receivable
Total Recorded Investment	3,413	3,687
Lease receivables
Past Due Financing Receivable
Total Recorded Investment	6,064	6,593
Recorded Investment Not Accruing	105	107
Lease receivables \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	330	328
Recorded Investment > 90 Days and Accruing	230	225
Billed Invoices > 90 Days and Accruing	31	36
Lease receivables \| Americas
Past Due Financing Receivable
Total Recorded Investment	3,526	3,911
Recorded Investment Not Accruing	59	44
Lease receivables \| Americas \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	268	239
Recorded Investment > 90 Days and Accruing	213	197
Billed Invoices > 90 Days and Accruing	27	29
Lease receivables \| EMEA
Past Due Financing Receivable
Total Recorded Investment	1,377	1,349
Recorded Investment Not Accruing	17	27
Lease receivables \| EMEA \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	26	32
Recorded Investment > 90 Days and Accruing	10	5
Billed Invoices > 90 Days and Accruing	2	3
Lease receivables \| Asia Pacific
Past Due Financing Receivable
Total Recorded Investment	1,161	1,333
Recorded Investment Not Accruing	29	36
Lease receivables \| Asia Pacific \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	36	57
Recorded Investment > 90 Days and Accruing	8	23
Billed Invoices > 90 Days and Accruing	2	3
Loan receivables
Past Due Financing Receivable
Total Recorded Investment	11,683	12,667
Recorded Investment Not Accruing	254	224
Loan receivables \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	523	498
Recorded Investment > 90 Days and Accruing	330	283
Billed Invoices > 90 Days and Accruing	39	41
Loan receivables \| Americas
Past Due Financing Receivable
Total Recorded Investment	6,118	6,715
Recorded Investment Not Accruing	128	96
Loan receivables \| Americas \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	382	345
Recorded Investment > 90 Days and Accruing	276	254
Billed Invoices > 90 Days and Accruing	27	38
Loan receivables \| EMEA
Past Due Financing Receivable
Total Recorded Investment	3,313	3,597
Recorded Investment Not Accruing	77	74
Loan receivables \| EMEA \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	62	90
Recorded Investment > 90 Days and Accruing	23	17
Billed Invoices > 90 Days and Accruing	4	0
Loan receivables \| Asia Pacific
Past Due Financing Receivable
Total Recorded Investment	2,252	2,354
Recorded Investment Not Accruing	49	54
Loan receivables \| Asia Pacific \| Total Past Due > 90 days
Past Due Financing Receivable
Recorded Investment > 90 Days	78	63
Recorded Investment > 90 Days and Accruing	31	12
Billed Invoices > 90 Days and Accruing	$ 8	$ 3

Billed invoices in financing receivables that are 90 days or more past due and still accruing.

No definition available.

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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- Definition

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

No definition available.

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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- Details

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