Borrowings (Short Term Debt Table) (Details 1) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Borrowings
Commercial paper	$ 650us-gaap_CommercialPaper	$ 2,458us-gaap_CommercialPaper
Short-term loans	480	551
Long-term debt - current maturities	4,601us-gaap_LongTermDebtCurrent	3,854us-gaap_LongTermDebtCurrent
Short Term Debt	5,731us-gaap_DebtCurrent	6,862us-gaap_DebtCurrent
Debt Disclosure
Tangible Assets Ratio	10.00%ibm_TangibleAssetsRatio
Net Interest Expense Ratio	2.20 to 1.0
Default provision on credit facility	$ 500ibm_DefaultProvisionOnCreditFacility
Commercial paper
Debt Disclosure
Weighted-average interest rates for short-term loans (as a percent)	0.10%	0.10%
Short-term loans
Debt Disclosure
Weighted-average interest rates for short-term loans (as a percent)	4.00%	5.10%

A default of at least this amount on other indebtedness would trigger a default on the credit facility.

No definition available.

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Ratio of interest expense calculated by consolidated adjusted cash flow to Consolidated net interest expense. It should not be less than the specified ratio as defined in debt covenant.

+ References

No definition available.

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Ratio calculated by assets net of liabilities and intangible assets over sale leaseback transactions. It is defined in debt covenant to rstrict a company from entering into sale leaseback transactions if in excess of this specified ratio.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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- Definition

Carrying amount at the balance sheet date of borrowings from a bank, not elsewhere enumerated in the taxonomy, with a maturity within one year (or within one operating cycle if longer) from the date of borrowing.

+ References

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- Definition

Weighted average interest rate of short-term debt outstanding.

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