Financing Receivables, Receivables Purchased/Participated from IBM - Past Due (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Past Due Financing Receivables
Period after which financing receivables become past due	90 days
Total Client Financing Receivables Portfolio Segment
Past Due Financing Receivables
Amortized cost/Recorded investment	$ 16,570	$ 17,848
Amortized cost/Recorded Investment > 90 Days and Accruing	271	245
Billed Invoices > 90 Days and Accruing	35	25
Amortized cost/Recorded Investment Not Accruing	172	171
Amortized cost/Recorded investment, impaired financing receivables with related allowance		128
Impaired financing receivables, related allowance	116	110
Total Client Financing Receivables Portfolio Segment \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	418	394
Total Client Financing Receivables Portfolio Segment \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment	8,948	10,049
Amortized cost/Recorded Investment > 90 Days and Accruing	230
Billed Invoices > 90 Days and Accruing	29
Amortized cost/Recorded Investment Not Accruing	96
Total Client Financing Receivables Portfolio Segment \| Americas \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	306
Total Client Financing Receivables Portfolio Segment \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment	4,759	4,796
Amortized cost/Recorded Investment > 90 Days and Accruing	30
Billed Invoices > 90 Days and Accruing	4
Amortized cost/Recorded Investment Not Accruing	68
Total Client Financing Receivables Portfolio Segment \| EMEA \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	93
Total Client Financing Receivables Portfolio Segment \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment	2,863	3,003
Amortized cost/Recorded Investment > 90 Days and Accruing	11
Billed Invoices > 90 Days and Accruing	2
Amortized cost/Recorded Investment Not Accruing	8
Total Client Financing Receivables Portfolio Segment \| Asia Pacific \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due	19
Lease receivables
Past Due Financing Receivables
Amortized cost/Recorded investment	3,888	4,274
Amortized cost/Recorded Investment > 90 Days and Accruing		156
Billed Invoices > 90 Days and Accruing		11
Amortized cost/Recorded Investment Not Accruing		59
Lease receivables \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		213
Lease receivables \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment		3,160
Amortized cost/Recorded Investment > 90 Days and Accruing		143
Billed Invoices > 90 Days and Accruing		10
Amortized cost/Recorded Investment Not Accruing		37
Lease receivables \| Americas \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		179
Lease receivables \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment		710
Amortized cost/Recorded Investment > 90 Days and Accruing		11
Billed Invoices > 90 Days and Accruing		1
Amortized cost/Recorded Investment Not Accruing		16
Lease receivables \| EMEA \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		24
Lease receivables \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment		404
Amortized cost/Recorded Investment > 90 Days and Accruing		2
Billed Invoices > 90 Days and Accruing		0
Amortized cost/Recorded Investment Not Accruing		7
Lease receivables \| Asia Pacific \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		9
Loan receivables
Past Due Financing Receivables
Amortized cost/Recorded investment	8,349	9,264
Amortized cost/Recorded Investment > 90 Days and Accruing		69
Billed Invoices > 90 Days and Accruing		11
Amortized cost/Recorded Investment Not Accruing		110
Loan receivables \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		161
Loan receivables \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment		6,173
Amortized cost/Recorded Investment > 90 Days and Accruing		66
Billed Invoices > 90 Days and Accruing		10
Amortized cost/Recorded Investment Not Accruing		56
Loan receivables \| Americas \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		107
Loan receivables \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment		2,415
Amortized cost/Recorded Investment > 90 Days and Accruing		3
Billed Invoices > 90 Days and Accruing		1
Amortized cost/Recorded Investment Not Accruing		51
Loan receivables \| EMEA \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		51
Loan receivables \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment		676
Amortized cost/Recorded Investment > 90 Days and Accruing		1
Billed Invoices > 90 Days and Accruing		0
Amortized cost/Recorded Investment Not Accruing		2
Loan receivables \| Asia Pacific \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		3
Long-term participated receivables from IBM
Past Due Financing Receivables
Amortized cost/Recorded investment	$ 4,333	4,310
Amortized cost/Recorded Investment > 90 Days and Accruing		20
Billed Invoices > 90 Days and Accruing		3
Amortized cost/Recorded Investment Not Accruing		2
Long-term participated receivables from IBM \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		21
Long-term participated receivables from IBM \| Americas
Past Due Financing Receivables
Amortized cost/Recorded investment		717
Amortized cost/Recorded Investment > 90 Days and Accruing		8
Billed Invoices > 90 Days and Accruing		1
Amortized cost/Recorded Investment Not Accruing		0
Long-term participated receivables from IBM \| Americas \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		8
Long-term participated receivables from IBM \| EMEA
Past Due Financing Receivables
Amortized cost/Recorded investment		1,671
Amortized cost/Recorded Investment > 90 Days and Accruing		7
Billed Invoices > 90 Days and Accruing		1
Amortized cost/Recorded Investment Not Accruing		1
Long-term participated receivables from IBM \| EMEA \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		7
Long-term participated receivables from IBM \| Asia Pacific
Past Due Financing Receivables
Amortized cost/Recorded investment		1,922
Amortized cost/Recorded Investment > 90 Days and Accruing		5
Billed Invoices > 90 Days and Accruing		1
Amortized cost/Recorded Investment Not Accruing		1
Long-term participated receivables from IBM \| Asia Pacific \| > 90 days
Past Due Financing Receivables
Amortized cost/Recorded Investment, Past Due		$ 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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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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