Financing Receivables (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivables
Ending Balance	$ 19,970ibm_FinancingReceivablesGross	$ 22,332ibm_FinancingReceivablesGross
Collectively evaluated for impairment	19,431	21,821
Individually evaluated for impairment	539	511
Allowance for Credit Losses
Allowance for credit losses, beginning balance	561	365
Write-offs	(1)	(24)
Provision	54	243
Other	(19)	(23)
Allowance for credit losses, ending balance	595	561
Collectively evaluated for impairment	80	81
Individually evaluated for impairment	515	480
Major Markets
Financing Receivables
Ending Balance	14,176	15,751
Collectively evaluated for impairment	14,098	15,665
Individually evaluated for impairment	78	86
Allowance for Credit Losses
Allowance for credit losses, beginning balance	111	137
Write-offs	(1)	(18)
Provision	5	3
Other	(8)	(12)
Allowance for credit losses, ending balance	107	111
Collectively evaluated for impairment	41	42
Individually evaluated for impairment	66	69
Growth Markets
Financing Receivables
Ending Balance	5,793	6,581
Collectively evaluated for impairment	5,332	6,156
Individually evaluated for impairment	461	425
Allowance for Credit Losses
Allowance for credit losses, beginning balance	450	228
Write-offs	(1)	(6)
Provision	49	240
Other	(11)	(11)
Allowance for credit losses, ending balance	488	450
Collectively evaluated for impairment	39	39
Individually evaluated for impairment	449	411
Lease receivables
Financing Receivables
Ending Balance	7,105	7,645
Allowance for Credit Losses
Allowance for credit losses, beginning balance			123
Allowance for credit losses, ending balance	188	165	123
Lease receivables \| Major Markets
Financing Receivables
Ending Balance	5,265	5,702
Allowance for Credit Losses
Allowance for credit losses, beginning balance			42
Allowance for credit losses, ending balance	32	32	42
Lease receivables \| Growth Markets
Financing Receivables
Ending Balance	1,840	1,943
Allowance for Credit Losses
Allowance for credit losses, beginning balance			80
Allowance for credit losses, ending balance	156	133	80
Loan receivables
Financing Receivables
Ending Balance	12,864	14,687
Allowance for Credit Losses
Allowance for credit losses, beginning balance			242
Allowance for credit losses, ending balance	408	396	242
Loan receivables \| Major Markets
Financing Receivables
Ending Balance	8,911	10,049
Allowance for Credit Losses
Allowance for credit losses, beginning balance			95
Allowance for credit losses, ending balance	75	79	95
Loan receivables \| Growth Markets
Financing Receivables
Ending Balance	3,953	4,639
Allowance for Credit Losses
Allowance for credit losses, beginning balance			147
Allowance for credit losses, ending balance	$ 332	$ 317	$ 147

Reduction to the allowance for credit losses related to transactions not otherwise specified in the taxonomy.

No definition available.

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Gross amount due from financing loans and leases, excluding current commercial financing receivables and other miscellaneous current financing receivables.

+ References

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A valuation allowance for financing receivables that are expected to be uncollectible.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of direct write-downs of financing receivables charged against the allowance.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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