Document and Entity Information Document Information [Table] Document Information [Line Items] Document Type Document Quarterly Report Document Transition Report Document Period End Date Entity File Number Entity Registrant Name Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Address, Address Line One Entity Address, City or Town Entity Address, State or Province Entity Address, Postal Zip Code City Area Code Local Phone Number Title of 12(b) Security Entity Central Index Key No Trading Symbol Flag Security Exchange Name Amendment Flag Entity Filer Category Entity Current Reporting Status Entity Interactive Data Current Entity Small Business Entity Emerging Growth Company Entity Shell Company Entity Common Stock, Shares Outstanding Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Period Focus CONSOLIDATED INCOME STATEMENT Statement [Table] Statement [Line Items] Statement Revenues [Abstract] Revenue Aggregate financing revenue, including income attributable to direct financing leases and loans, working capital financing and purchased interests in trade account receivables, which is excluded from the scope of ASC 606. Financing Revenue Financing revenue Operating Lease, Lease Income, Lease Payments Operating lease revenue Operating lease revenue Revenues Total revenue Revenue Amount of expense for financing costs recognized in the current period, including but not limited to, interest cost, related party cost, property tax cost, and insurance cost. Financing Cost Financing cost (related party cost of $49 in 2020 and $74 in 2019) Depreciation Depreciation Depreciation of equipment under operating lease Gross Profit Net margin Expense and Other Income [Abstract] Expense and other (income) Selling, General and Administrative Expense Selling, general and administrative Provision for Loan, Lease, and Other Losses Provision for/(benefit from) credit losses Provision for credit losses The aggregate amount of (income) expense , not previously categorized, including interest income, gains and losses on certain derivative instruments, gains and losses from securities and other investments, gains and losses from certain real estate transactions, foreign currency transaction gains and losses, gains and losses from the sale of businesses and amounts related to accretion of asset retirement obligations. Other Income and Expense Other (income) and expense The aggregate amount of both recurring costs and income associated with normal operations (except for the portion of these expenses which can be clearly related to production and included in cost of sales, services or financing) and expense (income) from ancillary business-related activities. Includes selling, general and administrative expense, research, development and engineering expense, intellectual property and custom development income and interest and debt related expenses (except those related to the financing activities of the entity). Expense and Other Income Total expense and other (income) Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Loss (income) from continuing operations before income taxes Pre-tax income Income before income taxes Income Tax Expense (Benefit) Provision for/(benefit from) income taxes Net Income (Loss) Attributable to Parent Net income Net income Interest Expense, Related Party Financing cost - related party Interest expense on debt payable to IBM Interest expense incurred on related party borrowings CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME Other Comprehensive Income (Loss), before Tax [Abstract] Other comprehensive income/(loss), before tax: Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax, Portion Attributable to Parent Foreign currency translation Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent Retirement-related benefit plans (1) Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Other comprehensive income/(loss), before tax Other comprehensive income/(loss), Before Tax Amount Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Income tax (expense)/benefit related to items of other comprehensive income Other comprehensive income/(loss), Tax (Expense)/Benefit Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Other comprehensive income/(loss), net of tax Other comprehensive income/(loss), net of tax Comprehensive Income (Loss), Net of Tax, Attributable to Parent Total comprehensive income/(loss) CONSOLIDATED BALANCE SHEET Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Loans And Finance Receivables [Member] Financing Receivable Portfolio Loans and leases receivable from a related party. Loans And Leases Receivable From Related Party [Member] Financing receivables from IBM Purchased and participated receivables from a related party. Purchased And Participated Receivables From Related Party [Member] Purchased and participated receivables from IBM Assets [Abstract] Assets: Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash and cash equivalents at end of period Cash and cash equivalents at beginning of period Cash and cash equivalents Financing Receivable, Net Net financing receivables Net financing receivables Financing receivables Property, Plant and Equipment, Net Equipment under operating leases (net of accumulated depreciation of $220 in 2020 and $238 in 2019) Due from Affiliates Other receivables from IBM Other receivables from IBM Other Assets. Other assets Assets Total assets Liabilities [Abstract] Liabilities: Accounts Payable Accounts payable Accounts Payable, Related Parties Accounts payable to related party Accounts payable to IBM Debt and Capital Lease Obligations Debt Notes Payable, Related Parties Debt payable to IBM Related party borrowings outstanding Taxes Payable Taxes Other Liabilities. Other liabilities Liabilities Total liabilities Members' Equity [Abstract] Member's interest: Members' Capital Member's interest Retained Earnings (Accumulated Deficit) Retained earnings Retained earnings Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income/(loss) Members' Equity Balance at the end of the period Balance at the beginning of the period Total member's interest Liabilities and Equity Total liabilities and member's interest Financing Receivable, Allowance for Credit Losses Allowance for credit losses Allowance for credit losses, ending balance Allowance for credit losses, beginning balance Receivables - allowances Allowance for credit losses Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Equipment under operating leases - accumulated depreciation CONSOLIDATED STATEMENT OF CASH FLOWS Net Cash Provided by (Used in) Operating Activities [Abstract] Cash flows from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to cash provided by operating activities: Deferred Income Tax Expense (Benefit) Deferred taxes Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee, and amount of income (expense) included in net income that results in no cash inflow (outflow), classified as other. Gain (Loss) on Disposition of Assets and Other Net (gain)/loss on asset sales and other Increase (Decrease) in Operating Capital [Abstract] Change in operating assets and liabilities: Increase (Decrease) in Operating Capital Other assets/other liabilities Net Cash Provided by (Used in) Operating Activities Net cash provided by operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from investing activities: Payments to Acquire Finance Receivables Originations of financing receivables Proceeds from Collection of Finance Receivables Collection of financing receivables The cash outflow for the purchase of amounts due from customers, clients, lessees, borrowers, or others under the terms of its agreements therewith. The cash inflows (outflows) associated with the originations and collection of financing receivables due in three months or less. Proceeds From Collections (Payments From Originations) of Financing Receivables Due In Three Months Or Less Short-term financing receivables - net (1) Payments to Acquire Equipment on Lease Purchase of equipment under operating leases Proceeds from Sales of Assets, Investing Activities Proceeds from disposition of equipment under operating lease Amount of cash inflow (outflow) related to receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Payments for (Proceeds from) Receivables from Affiliate Other receivables from IBM - net Payments for (Proceeds from) Other Investing Activities Other investing activities - net Net Cash Provided by (Used in) Investing Activities Net cash provided by investing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Cash flows from financing activities: Proceeds from Issuance of Long-term Debt and Capital Securities, Net Proceeds from issuance of debt Repayments of Long-term Debt, Long-term Capital Lease Obligations, and Capital Securities Principal payments on debt Proceeds from (Repayments of) Short-term Debt, Maturing in Three Months or Less Short-term borrowings/(repayments) - net Distribution Made to Limited Liability Company (LLC) Member, Cash Distributions Paid Distributions to IBM Net Cash Provided by (Used in) Financing Activities Net cash used in financing activities Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Effect of exchange rate changes on cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Net change in cash and cash equivalents CONSOLIDATED STATEMENT OF CHANGES IN MEMBER'S INTEREST Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Parent [Member] Total IBM Stockholders' Equity Member Units [Member] Member's Interest Retained Earnings [Member] Retained Earnings Accumulated Other Comprehensive Income [Member] Accumulated Other Comprehensive Income/(Loss) A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. Increase (Decrease) In Members Equity [Roll Forward] Member's Interest Cumulative Effect of New Accounting Principle in Period of Adoption Cumulative effect of change in accounting principle Adjustment for adoption of new standard Equity contributions from parent company. Equity Contributions From Parent Contributions from IBM Distribution Paid to Parent Company Distributions to IBM Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Basis of Presentation Accounting Changes Accounting Changes and Error Corrections [Text Block] Accounting Changes Segments Segment Reporting Disclosure [Text Block] Segments Divestiture Mergers, Acquisitions and Dispositions Disclosures [Text Block] Divestiture Financial Assets and Liabilities Financial Instruments Disclosure [Text Block] Financial Assets and Liabilities Financing Receivables, Receivables Purchased/Participated from IBM Financing Receivables [Text Block] Financing Receivables, Receivables Purchased/Participated from IBM Leases The entire disclosure of information about leases. Lease Disclosure [Text Block] Leases Borrowings Debt Disclosure [Text Block] Borrowings Commitments Commitments Disclosure [Text Block] Commitments Contingencies Legal Matters and Contingencies [Text Block] Contingencies Equity Activity Stockholders' Equity Note Disclosure [Text Block] Equity Activity Derivative Financial Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Derivative Financial Instruments Retirement-Related Benefits Pension and Other Postretirement Benefits Disclosure [Text Block] Retirement-Related Benefits Relationship with IBM and Related Party Transactions Related Party Transactions Disclosure [Text Block] Relationship with IBM and Related Party Transactions SIGNIFICANT ACCOUNTING POLICIES Accounting Policies Basis of Accounting, Policy [Policy Text Block] Basis of Presentation New Accounting Pronouncements, Policy [Policy Text Block] Accounting Changes Fair Value Measurement, Policy [Policy Text Block] Financial Assets and Liabilities Measured At Fair Value Disclosure of accounting policy for financial assets and liabilities not measured at fair value. Financial Assets And Liabilities Not Measured At Fair Value [Policy Text Block] Financial Assets and Liabilities Not Measured At Fair Value Disclosure of accounting policy for financing receivables, and receivables purchased and participated from a related party. Receivables Purchased and Participated from Related Party [Policy Text Block] Financing Receivables, Receivables Purchased/Participated from IBM Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts [Policy Text Block] Allowance for Credit Losses - Financing Receivables Disclosure of accounting policy for collectively evaluated financing receivables. Collectively Evaluated Financing Receivables [Policy Text Block] Collectively Evaluated Financing Receivables Disclosure of accounting policy for client financing receivables by portfolio segment. Financing Receivables By Portfolio Segment [Policy Text Block] Client Financing Receivables Disclosure of accounting policy for financing receivables past due. Financing Receivables Past Due [Policy Text Block] Past Due Financing Receivables Guarantees, Indemnifications and Warranties Policies [Policy Text Block] Commitments Disclosure of accounting policy for contingencies, which may include policies for recognizing and measuring loss and gain contingencies. Contingencies, Policy [Policy Text Block] Contingencies Derivatives, Policy [Policy Text Block] Derivative Financial Instruments Schedule of Segment Reporting Information, by Segment [Table Text Block] Reporting information by segment Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Financial assets and financial liabilities measured at fair value on a recurring basis Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Components of financing receivables and receivables purchased/participated from IBM Allowance for Credit Losses on Financing Receivables [Table Text Block] Schedule of financing receivables by portfolio segment Past Due Financing Receivables [Table Text Block] Schedule of past due financing receivables Financing Receivable Credit Quality Indicators [Table Text Block] Schedule of net recorded investment by credit quality indicators Tabular disclosure of components of lease income from operating leases, direct financing and sale type leases. Operating Lease, Direct Financing and Sales Type Lease, Lease Income [Table Text Block] Summary of lease income included in Consolidated Statements of Earnings Schedule of Short-term Debt [Table Text Block] Short-Term Debt Schedule of Long-term Debt Instruments [Table Text Block] Long-Term Debt Schedule of Maturities of Long-term Debt [Table Text Block] Contractual obligations of long-term debt and long-term debt payable to IBM outstanding Comprehensive Income (Loss) [Table Text Block] Reclassifications and Taxes Related to Items of Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Accumulated Other Comprehensive Income/(Loss) (net of tax) Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Amounts related to cumulative basis adjustments for fair value hedges Derivative Instruments, Gain (Loss) [Table Text Block] Effect of Derivative Instruments in the Consolidated Statement of Earnings New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Accounting Changes Schedule of Segment Reporting Information, by Segment [Table] Segments [Axis] Segment [Domain] Segments [Domain] Client financing. Client Financing [Member] Client Financing Commercial financing. Commercial Financing [Member] Commercial Financing Segment Reporting Information [Line Items] Segment Information Number of Reportable Segments Number of reportable segments Segment Reporting Information, Operating Income (Loss) [Abstract] Segments, Income statement information Interest Expense Interest expense Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Table] Disposal Group Name [Axis] Disposal Groups Including Discontinued Operations Name [Domain] Disposal Groups, Including Discontinued Operations, Name [Domain] Information pertaining to the commercial financing business. Commercial Financing Business [Member] Commercial financing business Related Party [Axis] Related Party [Domain] Related Party [Domain] International Business Machines. International Business Machines [Member] IBM Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Divestiture Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal Gain on divestiture Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Fair Value Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value Measurements Recurring [Member] Recurring Fair Value, Hierarchy [Axis] Fair Value Measurements Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value Inputs Level1 [Member] Level 1 Fair Value Inputs Level2 [Member] Level 2 Cash and Cash Equivalents [Axis] Restricted Cash And Cash Equivalents Cash And Cash Equivalents [Member] Cash and Cash Equivalents [Domain] Bank Time Deposits [Member] Time deposits and certificates of deposit Money Market Funds [Member] Money market funds Derivative Instrument [Axis] Derivative Contract Type [Domain] Derivative Contract [Domain] Interest Rate Contract [Member] Interest rate contracts Foreign Exchange Contract [Member] Foreign exchange contracts Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Financial Instruments - Fair Value Measurements Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract] Financial assets and financial liabilities measured at fair value on a recurring basis: Cash and Cash Equivalents, Fair Value Disclosure Cash equivalents Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement Fair value of derivative assets Derivative assets Assets, Fair Value Disclosure Total assets Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement Fair value of derivative liabilities Derivative liabilities Financial and Nonfinancial Liabilities, Fair Value Disclosure Total liabilities Derivative Asset, Not Offset, Policy Election Deduction Potential reduction in net position of total derivative assets Assets included in master netting arrangements Derivative Liability, Not Offset, Policy Election Deduction Potential reduction in net position of total derivative liabilities Liabilities included in master netting arrangements Debt Securities, Available-for-sale, Allowance for Credit Loss, Period Increase (Decrease) Impairment for credit losses Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Recognized in Earnings Available-for-sale securities impairment Debt Instrument, Fair Value Disclosure [Abstract] Long-Term Debt Long-term Debt, Excluding Current Maturities Carrying amount of long-term debt Long-term Debt, Fair Value Fair value of long-term debt Loans and Leases Receivable Disclosure [Table] Loans and Leases Receivable Disclosure [Line Items] FINANCING RECEIVABLES, RECEIVABLES PURCHASED Financing Receivable, Net [Abstract] Financing receivables Term of financing receivables, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Financing Receivable, Payment Terms Financing receivable, payment terms Loans and Leases Receivable before Fees, Gross Financing receivables, gross Loans and Leases Receivable, Deferred Income Unearned income Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums Deferred initial direct costs The estimate of the financing receivable's economic value at the end of the lease term that includes both the guaranteed and unguaranteed residual value. Financing Receivable Guaranteed and Unguaranteed Residual Asset Residual value Loans and Leases Receivable, Net of Deferred Income Amortized cost/Recorded investment Amortized cost/Recorded investment Direct Financing Lease, Unguaranteed Residual Asset Unguaranteed residual value Unguaranteed residual value The estimate of the lease property's economic value at the end of the lease term that is guaranteed by either the lessee or a third-party. Capital Leases, Guaranteed Residual Values of Leased Property Guaranteed residual value Loans and Leases Receivable, Collateral for Secured Borrowings Financing receivables pledged as collateral for borrowings Receivables Held-for-sale, Amount Financing receivables held for sale Amount of allowance for credit loss on financing receivable and including related off-balance sheet commitments. Financing Receivable Allowance For Credit Losses Including Related Off Balance Sheet Commitments Receivables - allowances, including off-balance sheet commitments Period of time in which economic forecasts can be reasonable and supportable. Reasonable And Supportable Economic Forecast Period Duration Forecast duration Portfolio segments of the company's total financing receivables related to finance leases, loans receivable, and participated loans. Finance Leases Portfolio And Loans Receivable And Participated Loans [Member] Finance leases portfolio and loans receivable and participated loans Finance Leases Portfolio Segment [Member] Lease receivables Loans Receivable [Member] Loan receivables Geographical [Axis] Segment Geographical [Domain] Geographical [Domain] Americas [Member] Americas E M E A [Member] EMEA Asia Pacific [Member] Asia Pacific Financing Receivable, Collectively Evaluated for Impairment Recorded investment collectively evaluated for impairment Financing Receivable, Individually Evaluated for Impairment Recorded investment individually evaluated for impairment Financing Receivable, Allowance for Credit Losses [Roll Forward] Allowance for credit losses: Financing Receivable, Allowance for Credit Losses, Write-downs Write-offs Financing Receivable, Allowance for Credit Losses, Recovery Recoveries Provision for Loan and Lease Losses Provision Allowance for Loan and Lease Losses, Foreign Currency Translation Foreign currency translation adjustment Allowance for Loan and Lease Losses, Adjustments, Other Other Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment Related allowance, collectively evaluated for impairment Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment Related allowance, individually evaluated for impairment Number of portfolio segments. Portfolio segment is a level at which an entity develops and documents a systematic methodology to determine its allowance for credit losses. Financing Receivable Number Of Portfolio Segments Number of portfolio segments Number of the classes of financing receivables. Classes of financing receivables generally are a disaggregation of a portfolio segment. Financing Receivable, Number Of Classes Of Financing Receivable Number of classes of financing receivable Schedule of Financing Receivables Past Due [Table] Participated receivables from a related party. Long Term Participated Receivables From Related Party [Member] Long-term participated receivables from IBM Financing Receivables, Period Past Due [Axis] Financing Receivables Period Past Due [Domain] Financing Receivables, Period Past Due [Domain] Financing Receivables Equal To Greater Than90 Days Past Due [Member] > 90 days Financing Receivable, Recorded Investment, Past Due [Line Items] Past Due Financing Receivables Period after which financing receivables become past due if payment has not been received. Period After Which Financing Receivables Become Past Due Period after which financing receivables become past due Financing Receivable, Recorded Investment, Past Due Amortized cost/Recorded Investment, Past Due Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing Amortized cost/Recorded Investment > 90 Days and Accruing Billed invoices in financing receivables that are 90 days or more past due and still accruing. Financing Receivable, Billed Invoices, 90 Days Past Due and Still Accruing Billed Invoices > 90 Days and Accruing Financing Receivable, Recorded Investment, Nonaccrual Status Amortized cost/Recorded Investment Not Accruing Impaired Financing Receivable, with Related Allowance, Recorded Investment Amortized cost/Recorded investment, impaired financing receivables with related allowance Impaired Financing Receivable, Related Allowance Impaired financing receivables, related allowance Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Financing Receivable, Recorded Investment [Line Items] Amortized cost/recorded investment for each class of receivables, by credit quality indicator Credit Quality Financing Receivable, Originated in Current Fiscal Year 2020 Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year 2019 Financing Receivable, Originated Two Years before Latest Fiscal Year 2018 Financing Receivable, Originated Three Years before Latest Fiscal Year 2017 Financing Receivable, Originated Four Years before Latest Fiscal Year 2016 Financing Receivable, Originated Five or More Years before Latest Fiscal Year 2015 and prior Credit Rating, Moody's [Axis] External Credit Rating Moodys [Member] External Credit Rating, Moody's [Domain] Aaa to Aa3 credit rating as defined by the external credit rating agency, Moody's. Moodys Aaa To Aa3 Rating [Member] Aaa - Aa3 A1 to A3 credit rating as defined by the external credit rating agency, Moody's. Moodys A1 To A3 Rating [Member] A1 - A3 Baa1 to Baa3 credit rating as defined by the external credit rating agency, Moody's. Moodys Baa1 To Baa3 Rating [Member] Baa1 - Baa3 Ba1 to Ba2 credit rating as defined by the external credit rating agency, Moody's. Moodys Ba1 To Ba2 Rating [Member] Ba1 - Ba2 Ba3 to B1 credit rating as defined by the external credit rating agency, Moody's. Moodys Ba3 To B1 Rating [Member] Ba3 - B1 B2 to B3 credit rating as defined by the external credit rating agency, Moody's. Moodys B2 To B3 Rating [Member] B2 - B3 Caa to D credit rating as defined by the external credit rating agency, Moody's. Moodys Caa To D Rating [Member] Caa - D 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, net of any write-downs taken for collection uncertainty on the part of the holder, excluding residual value in the case of leases. Financing Receivables, Net, Excluding Residual Value Financing receivables, net recorded investment Financing Receivable, Modifications, Recorded Investment Troubled debt restructurings of financing receivables Amount of lease income from variable lease payments, interest income, and profit (loss) recognized at commencement. Direct Financing Lease And Sales Type Lease Lease Income Financing lease revenue Operating Lease, Variable Lease Income Variable lease revenue Lease Income Total lease revenue Lessor, Lease, Description [Table] Lessor, Lease, Description [Line Items] Maturity analysis of lease payments due Schedule of Short-term Debt [Table] Short-term Debt, Type [Axis] Short Term Debt Type [Domain] Short-term Debt, Type [Domain] Loans Payable [Member] Debt Commercial Paper [Member] Commercial paper Loans payable that are short-term. Short Term Loans Payable [Member] Short-term loans Secured Debt [Member] Secured borrowings Borrowings from a related party that is supported by a written promise to pay an obligation. Loans Payable To Related Party [Member] Debt payable to IBM Short-term Debt [Line Items] Short-Term Debt Short-term Debt Short-term debt Line of Credit Facility, Maximum Borrowing Capacity Revolving line of credit, amount Maximum aggregate amount permitted to be outstanding at any one time Debt Instrument, Term Revolving line of credit, term Term of debt instrument Short-term Debt, Weighted Average Interest Rate Weighted-average interest rates for short-term loans (as a percent) The aggregate value of short-term loans and leases receivable that serve as collateral for obligations arising from a transfer of financial assets recorded as short-term secured borrowing. Short-term Loans And Leases Receivable Collateral For Short-term Secured Borrowings Short-term financing receivables pledged as collateral for short-term secured borrowings Schedule of Long-term Debt Instruments [Table] Debt Instrument [Axis] Debt Instrument Name [Domain] Debt Instrument, Name [Domain] Notes Payable Other Payables [Member] Long-term notes A written promise to pay a note to a third party, with maturities in 2020. Notes Payable Other Payables Maturing2020 [Member] Long-term notes maturing in 2020 A written promise to pay a note to a third party, with maturities in 2021. Notes Payable Other Payables Maturing2021 [Member] Long-term notes maturing in 2021 A written promise to pay a note to a third party, with maturities in 2022. Notes Payable Other Payables Maturing2022 [Member] Long-term notes maturing in 2022 A written promise to pay a note to a third party, with maturities in 2023. Notes Payable Other Payables Maturing2023 [Member] Long-term notes maturing in 2023 Loans payable that are long-term. Long Term Loans Payable [Member] Long-term loans Debt Instrument [Line Items] Borrowings Long-term Debt, Weighted Average Interest Rate Debt instrument, weighted-average interest rate percentage (as a percent) Long-term Debt, Gross Long-term debt - gross Total Debt Instrument, Unamortized Discount Less: net unamortized discount Debt Issuance Costs, Net Less: net unamortized debt issuance costs Derivative, Fair Value, Net Add: fair value adjustment Long-term Debt Long-term debt - net The aggregate value of long-term loans and leases receivable that serve as collateral for obligations arising from a transfer of financial assets recorded as long-term secured borrowing. Long-term Loans And Leases Receivable Collateral For Long-term Secured Borrowings Long-term financing receivables pledged as collateral for long-term secured borrowings The maximum percentage of lien over the entity's consolidated net tangible assets under covenants. Maximum percentage of liens over entity's net tangible assets Maximum percent of lien over the net tangible assets Long-term Debt, Fiscal Year Maturity [Abstract] Contractual maturities of long-term debt Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year 2020 (Q2-Q4) Long-term Debt, Maturities, Repayments of Principal in Year Two 2021 Long-term Debt, Maturities, Repayments of Principal in Year Three 2022 Long-term Debt, Maturities, Repayments of Principal in Year Four 2023 Long-term Debt, Maturities, Repayments of Principal in Year Five 2024 Long-term Debt, Maturities, Repayments of Principal after Year Five 2025 and beyond Interest Costs Incurred [Abstract] Interest on Debt Interest Expense, Debt Interest expense Line of Credit Facility [Table] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Credit Facility [Member] Lines of Credit Credit agreements entered into on July 20, 2017, under which the entity and a parent borrower may borrow funds on a revolving basis. New Credit Agreements [Member] New Credit Agreements Credit agreement with an original term of 364 days, entered into on July 18, 2019, under which the entity and a subsidiary borrower may borrow funds on a revolving basis. Credit Agreement364 Days2019 [Member] 364-Day Credit Agreement, 2019 Credit agreement with an original term of three years, entered into on July 20, 2017, under which the entity and a parent borrower may borrow funds on a revolving basis. Three Year Credit Agreement [Member] Three-Year Credit Agreement Line of Credit Facility [Line Items] Lines of Credit Long-term Line of Credit Revolving line of credit, borrowings outstanding Long-term Debt, Other Disclosures [Abstract] Covenants The limit on secured indebtedness and sale and leaseback transactions expressed as a percentage of the parent company's consolidated net tangible assets. This limit is part of covenant contained in the company's indentures which govern its debt securities and various credit facilities. Debt Covenant Limit Based On Net Tangible Assets Limit based on net tangible assets Period over which the entity's net interest expense ratio is calculated for determining compliance with debt covenants. Period for Net Interest Expense Ratio Period for calculation of net interest expense ratio The minimum ratio of interest expense specified in the reporting entity's debt agreements which the reporting entity must maintain in order to be in compliance. Net Interest Expense Ratio Minimum net interest expense ratio The minimum tangible net worth that the entity is required to maintain per the terms of the debt agreement. Debt Covenant, Minimum Tangible Net Worth Financial covenant - minimum tangible net worth The maximum leverage ratio that the entity is permitted per the terms of the debt agreement. Debt Covenant, Maximum Leverage Ratio Financial covenant - maximum leverage ratio The limit on the amount of a default on other indebtedness which would trigger a default under the reporting entity's credit facility. Default Provision On Credit Facility Default provision on credit facility Other Commitments [Table] Other Commitments [Axis] Other Commitments [Domain] Other Commitments [Domain] The entity's commitment to provide extended lines of credit to third-party entities. Extended Lines Of Credit [Member] Extended lines of credit The entity's commitment to provide future financing to its clients in connection with client purchase agreements. Financing For Purchase Agreements [Member] Financing for client purchase agreements Other Commitments [Line Items] Commitments Unused Commitments to Extend Credit Unused amounts in lines of credit to third-party entities and commitments for future financing to clients Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Translation Adjustment [Member] Foreign Currency Translation Adjustments Accumulated Defined Benefit Plans Adjustment [Member] Net Change Retirement-Related Benefit Plans Accumulated Defined Benefit Plans Adjustment Net Prior Service Cost Credit [Member] Retirement-Related Benefit Plans, Prior Service Costs/(Credits) Accumulated Defined Benefit Plans Adjustment Net Unamortized Gain Loss [Member] Retirement-Related Benefit Plans, Net Gains/(Losses) Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income/(Loss) (net of tax) Reclassifications and Taxes Related to Items of Other Comprehensive Income Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Unrealized gains (losses) on cash flow hedges Debt Securities, Available-for-sale, Gain (Loss) Gains (losses) on available-for-sale-debt securities Other Comprehensive Income (Loss), before Reclassifications, before Tax Other comprehensive income/(loss), arising during the period, Before Tax Amount Other Comprehensive Income (Loss) before Reclassifications, Tax Other comprehensive income/(loss), arising during the period, Tax (Expense)/Benefit Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Other comprehensive income before reclassification Other comprehensive income before reclassification Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Reclassification/amortization, Before Tax Amount Reclassification from AOCI, Current Period, Tax Reclassification/amortization, Tax (Expense)/Benefit Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Amount reclassified from accumulated other comprehensive income Reclassification/amortization, Net of Tax Amount Derivative [Table] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Not Designated As Hedging Instrument Economic Hedge [Member] Derivative instruments not designated as hedging instruments Hedging Relationship [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Fair Value Hedging [Member] Fair value hedges Cash Flow Hedging [Member] Cash flow hedges Net Investment Hedging [Member] Net investment hedges Interest Rate Swap [Member] Interest rate swaps Counterparty Name [Axis] Repurchase Agreement Counterparty Name [Domain] Counterparty Name [Domain] Represents information pertaining to third parties. Third Parties [Member] Third parties Range [Axis] Range [Member] Range [Domain] Maximum [Member] Maximum Derivative [Line Items] Derivative Financial Instruments Derivative, Notional Amount Notional amount Derivative, Average Remaining Maturity Average remaining maturity Derivative, Term of Contract Term of derivative contract Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Derivatives, Fair Value [Line Items] Fair Values of Derivative Instruments Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Primary financial statement caption encompassing debt, including short-term and long-term debt. Debt Current And Noncurrent [Member] Debt Hedged Liability, Fair Value Hedge Carrying amount of the hedged item Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease) Cumulative hedging adjustments included in the carry amount - assets/(liabilities) Derivative Instruments, Gain (Loss) [Table] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Primary financial statement caption in which reported facts about the cost of financing have been included. Cost Of Financing [Member] Financing cost Primary financial statement caption in which reported facts about other income and expense (operating and nonoperating) have been included. Other Income Expense [Member] Other (income) and expense Derivative Instruments, Gain (Loss) [Line Items] The Effect of Derivative Instruments in the Consolidated Statement of Earnings Gain (Loss) on Derivative Instruments, Net, Pretax Gains/(losses) of Total hedge activity Derivative, Gain (Loss) on Derivative, Net Gain/(Loss) Recognized in Earnings, Recognized on Derivatives Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge Gain/(Loss) Recognized in Earnings, Attributable to Risk Being Hedged OCI, before Reclassifications, before Tax, Attributable to Parent Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Recognized in OCI Derivative, Excluded Component, Gain (Loss), Recognized in Earnings Gain (Loss) Recognized in Earnings and Other Comprehensive Income - Amounts Excluded from Effectiveness Testing Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net Gains (losses) excluded from the assessment of hedge effectiveness for fair value hedges Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] A Support Agreement between the reporting entity and the parent entity. Support Agreement With Parent Entity [Member] Support Agreement Ownership [Axis] Ownership [Domain] Ownership [Domain] IBM Credit LLC. Ibm Credit Llc [Member] IBM Credit LLC Legal Entity [Axis] Entity [Domain] Entity [Domain] Related Party Transaction [Line Items] Related party transactions The minimum direct or indirect ownership in the reporting entity which the parent entity has agreed to retain, pursuant to a support agreement. Minimum Beneficial Ownership Equity Voting Interests Percentage Minimum beneficial ownership of equity voting interest (as a percent) The minimum tangible net worth which the parent entity has agreed to cause the reporting entity to have, pursuant to a support agreement. Minimum Consolidated Tangible Net Worth Minimum consolidated tangible net worth to be supported by parent company The maximum debt to equity ratio of the reporting entity, which, if exceeded, triggers a capital contribution to the reporting entity by the parent entity. Maximum Debt To Equity Ratio Maximum debt to equity ratio to be supported by parent company Purchased receivables from a related party. Short Term Purchased Receivables From Related Party [Member] Short-term purchased receivables from IBM Primary financial statement caption encompassing financing revenue. Financial Services Revenue [Member] Financing revenue Investment Type [Axis] Investment Type Categorization [Member] Investments [Domain] Excess cash in short-term interest-bearing accounts with parent company, that is presented as other assets. Excess Cash In Short Term Interest Bearing Accounts With Parent [Member] Excess cash in short-term interest-bearing accounts with parent Related Party Fees and Other Arrangements, Limited Liability Company (LLC) or Limited Partnership (LP) [Abstract] Disclosures Interest Income, Related Party Interest income from a related party The increase (decrease) in interest income earned from a related party over the prior year. Related Party Information, Interest Income, Change Increase (decrease) in interest income over the prior year Amount of revenue earned from financing of related party trade receivables. Trade Receivable Finance Revenue from Related Party Financing revenue The increase (decrease) in finance income earned from a related party over the prior year. Related Party Information, Financial Services Revenue Change Increase (decrease) in financial services revenue over the prior year Fee income earned from related parties related to financing incentives to a third party. Fee Income From Related Party Related To Financing Incentives To Third Party Fee income from related party related to financing incentives to third party The change from year to year in the fee income earned from related parties. Related Party Information, Fee Income, Change Change in fee income Sales to a related party of equipment returned from lease. Sales Of Returned Equipment [Member] Sales of returned equipment Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party Selling, general and administrative expense with related party Amount of net profit from transactions with related parties. Related Party Transaction, Net Profit Net profit on transaction with related party Effective Income Tax Rate Reconciliation, Percent Effective rate on continuing operations The net benefit amount from the recognition of a deferred tax asset. Net Benefit Of Deferred Tax Asset Discrete tax benefit Tax Cuts and Jobs Act of 2017, Measurement Period Adjustment, Income Tax Expense (Benefit) Additional provisional charge (benefit) resulting from guidance related to U.S. tax reform Restatement [Axis] Restatement [Domain] Restatement [Domain] Restatement Adjustment [Member] Adjustment Adjustments for New Accounting Pronouncements [Axis] Type Of Adoption [Member] Type of Adoption [Domain] Accounting Standards Update201613 [Member] ASU 2016-13 Disposal Group Classification [Axis] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Disposal Group Disposed Of By Sale Not Discontinued Operations [Member] Disposal Group, Disposed of by Sale Commercial Loan [Member] Commercial financing receivables Minimum [Member] Minimum Aaa to Baa3 credit rating as defined by the external credit rating agency, Moody's. Moodys Aaa To Baa3 Rating [Member] Aaa - Baa3 Moodys rating Ba1 to D. Moodys Ba1 To D Rating [Member] Ba1 - D