The percent of goodwill arising from a business combination that is expected to be deductible for tax purposes.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Balance Type:	credit
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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ACQUISITIONS/DIVESTITURES - Businesses Acquired, 2015 (Details) $ in Millions			3 Months Ended	12 Months Ended
	Nov. 06, 2015 USD ($)	Oct. 13, 2015 USD ($)	Dec. 31, 2015 USD ($) item	Dec. 31, 2015 USD ($) item	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
ACQUISITIONS
Goodwill			$ 32,021	$ 32,021	$ 36,788	$ 36,199
Cognitive Solutions
ACQUISITIONS
Goodwill			15,621	15,621	19,665	19,484
Technology Services & Cloud Platforms
ACQUISITIONS
Goodwill			10,156	10,156	10,447	10,258
Global Business Services
ACQUISITIONS
Goodwill			4,396	4,396	4,813	4,607
Systems
ACQUISITIONS
Goodwill			1,848	$ 1,848	$ 1,862	$ 1,850
2015 Acquisitions
ACQUISITIONS
Businesses acquired, number (in entities) \| item				14
Businesses acquired, aggregate cost				$ 3,555
Merge
ACQUISITIONS
Percentage of business acquired (as a percent)		100.00%
Businesses acquired, cash consideration		$ 1,036
Goodwill		$ 695
Expected percent of goodwill deductible for tax purposes		0.00%
Acquired intangible asset, weighted average useful life		7 years
Merge \| Cognitive Solutions
ACQUISITIONS
Goodwill		$ 502
Merge \| Technology Services & Cloud Platforms
ACQUISITIONS
Goodwill		$ 193
Cleversafe
ACQUISITIONS
Percentage of business acquired (as a percent)	100.00%
Businesses acquired, cash consideration	$ 1,309
Goodwill	$ 1,000
Expected percent of goodwill deductible for tax purposes	0.00%
Acquired intangible asset, weighted average useful life	6 years 10 months 24 days
Cleversafe \| Technology Services & Cloud Platforms
ACQUISITIONS
Goodwill	$ 590
Cleversafe \| Systems
ACQUISITIONS
Goodwill	$ 410
Other 2015 Acquisitions
ACQUISITIONS
Goodwill			895	$ 895
Expected percent of goodwill deductible for tax purposes				7.00%
Acquired intangible asset, weighted average useful life				6 years 4 months 24 days
Other 2015 Acquisitions \| Cognitive Solutions
ACQUISITIONS
Businesses acquired, number (in entities) \| item				6
Goodwill			518	$ 518
Other 2015 Acquisitions \| Technology Services & Cloud Platforms
ACQUISITIONS
Businesses acquired, number (in entities) \| item				4
Goodwill			$ 303	$ 303
Other 2015 Acquisitions \| Global Business Services
ACQUISITIONS
Businesses acquired, number (in entities) \| item			2
Goodwill			$ 74	$ 74
AlchemyAPI
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Blekko
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Explorys
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Phytel
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Compose
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
IRIS Analytics
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Blue Box
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
StrongLoop
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Gravitant
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Clearleap
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%
Meteorix
ACQUISITIONS
Percentage of business acquired (as a percent)			100.00%	100.00%