Financing Receivables, Receivables Purchased/Participated from IBM - Past Due (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Past Due Financing Receivables
Period after which financing receivables become past due	90 days
Finance leases portfolio and loans receivable and participated loans
Past Due Financing Receivables
Amortized cost/Recorded investment	$ 16,997	$ 17,848
Amortized cost/Recorded Investment > 90 Days and Accruing	195	245
Billed Invoices > 90 Days and Accruing	23	25
Amortized cost/Recorded Investment Not Accruing	149	171
Amortized cost/Recorded investment, impaired financing receivables with related allowance		128
Impaired financing receivables, related allowance	95	110
Finance leases portfolio and loans receivable and participated loans \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	333	394
Finance leases portfolio and loans receivable and participated loans \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment	9,626	10,049
Finance leases portfolio and loans receivable and participated loans \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment	4,534	4,796
Finance leases portfolio and loans receivable and participated loans \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment	2,836	3,003
Lease receivables
Past Due Financing Receivables
Amortized cost/Recorded investment	4,314	4,274
Amortized cost/Recorded Investment > 90 Days and Accruing	115	156
Billed Invoices > 90 Days and Accruing	7	11
Amortized cost/Recorded Investment Not Accruing	56	59
Lease receivables \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	164	213
Lease receivables \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment	3,338	3,160
Amortized cost/Recorded Investment > 90 Days and Accruing	106	143
Billed Invoices > 90 Days and Accruing	7	10
Amortized cost/Recorded Investment Not Accruing	35	37
Lease receivables \| Americas \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	136	179
Lease receivables \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment	601	710
Amortized cost/Recorded Investment > 90 Days and Accruing	6	11
Billed Invoices > 90 Days and Accruing	0	1
Amortized cost/Recorded Investment Not Accruing	15	16
Lease receivables \| EMEA \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	19	24
Lease receivables \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment	376	404
Amortized cost/Recorded Investment > 90 Days and Accruing	3	2
Billed Invoices > 90 Days and Accruing	0	0
Amortized cost/Recorded Investment Not Accruing	6	7
Lease receivables \| Asia Pacific \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	9	9
Loan receivables
Past Due Financing Receivables
Amortized cost/Recorded investment	8,476	9,264
Amortized cost/Recorded Investment > 90 Days and Accruing	72	69
Billed Invoices > 90 Days and Accruing	14	11
Amortized cost/Recorded Investment Not Accruing	90	110
Loan receivables \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	158	161
Loan receivables \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment	5,657	6,173
Amortized cost/Recorded Investment > 90 Days and Accruing	60	66
Billed Invoices > 90 Days and Accruing	10	10
Amortized cost/Recorded Investment Not Accruing	38	56
Loan receivables \| Americas \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	97	107
Loan receivables \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment	2,219	2,415
Amortized cost/Recorded Investment > 90 Days and Accruing	7	3
Billed Invoices > 90 Days and Accruing	3	1
Amortized cost/Recorded Investment Not Accruing	50	51
Loan receivables \| EMEA \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	55	51
Loan receivables \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment	600	676
Amortized cost/Recorded Investment > 90 Days and Accruing	5	1
Billed Invoices > 90 Days and Accruing	0	0
Amortized cost/Recorded Investment Not Accruing	1	2
Loan receivables \| Asia Pacific \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	7	3
Long-term participated receivables from IBM
Past Due Financing Receivables
Amortized cost/Recorded investment	4,206	4,310
Amortized cost/Recorded Investment > 90 Days and Accruing	9	20
Billed Invoices > 90 Days and Accruing	2	3
Amortized cost/Recorded Investment Not Accruing	4	2
Long-term participated receivables from IBM \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	12	21
Long-term participated receivables from IBM \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment	631	717
Amortized cost/Recorded Investment > 90 Days and Accruing	5	8
Billed Invoices > 90 Days and Accruing	1	1
Amortized cost/Recorded Investment Not Accruing	3	0
Long-term participated receivables from IBM \| Americas \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	7	8
Long-term participated receivables from IBM \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment	1,715	1,671
Amortized cost/Recorded Investment > 90 Days and Accruing	0	7
Billed Invoices > 90 Days and Accruing	0	1
Amortized cost/Recorded Investment Not Accruing	1	1
Long-term participated receivables from IBM \| EMEA \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	1	7
Long-term participated receivables from IBM \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment	1,860	1,922
Amortized cost/Recorded Investment > 90 Days and Accruing	4	5
Billed Invoices > 90 Days and Accruing	1	1
Amortized cost/Recorded Investment Not Accruing	0	1
Long-term participated receivables from IBM \| Asia Pacific \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	$ 4	$ 6

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

No definition available.

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- Definition

Period after which financing receivables become past due if payment has not been received.

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- Definition

Amount of financing receivable 90 days or more past due and still accruing.

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- Definition

Amount of financing receivable on nonaccrual status.

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- Definition

Amount of financing receivable past due.

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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.

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- Definition

Amount of allowance for credit losses related to recorded investment.

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- Definition

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

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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.

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