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=26713463&loc=d3e16265-109275

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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=56956515&loc=d3e1392-128463

+ Details

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- 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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- 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
-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

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- 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
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: 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=56944662&loc=d3e3213-108585

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Acquisitions/Divestitures (Details 1) $ in Millions					1 Months Ended	3 Months Ended			12 Months Ended
Acquisitions/Divestitures (Details 1) $ in Millions	Jan. 29, 2016 USD ($)	Nov. 06, 2015 USD ($)	Oct. 13, 2015 USD ($)	Jul. 03, 2013 USD ($)	Feb. 18, 2016 USD ($)	Dec. 31, 2015 USD ($) Acquisition	Sep. 30, 2013 Acquisition	Jun. 30, 2013 Acquisition	Dec. 31, 2015 USD ($) Acquisition	Dec. 31, 2014 USD ($) Acquisition	Dec. 31, 2013 USD ($) Acquisition
Acquisitions:
Businesses acquired, number (in entities) \| Acquisition									14	6	10
Businesses acquired, aggregate cost									$ 3,555	$ 608	$ 3,219
Goodwill						$ 32,021			32,021	30,556	31,184
Cognitive Solutions
Acquisitions:
Goodwill						15,621			15,621	15,156	15,244
GBS
Acquisitions:
Goodwill						4,396			4,396	4,555	4,855
Technology Services & Cloud Platforms
Acquisitions:
Goodwill						10,156			10,156	9,373	9,485
Systems
Acquisitions:
Goodwill						1,848			1,848	$ 1,472	1,601
SoftLayer
Acquisitions:
Percentage of business acquired				100.00%
Businesses acquired, cash consideration				$ 1,977
Goodwill				$ 1,285							$ 1,285
Expected percent of goodwill deductible for tax purposes				0.00%
Acquired intangible asset, weighted average useful life											7 years
SoftLayer \| Cognitive Solutions
Acquisitions:
Goodwill				$ 28
SoftLayer \| Technology Services & Cloud Platforms
Acquisitions:
Goodwill				$ 1,257
Merge
Acquisitions:
Percentage of business acquired			100.00%
Businesses acquired, cash consideration			$ 1,036
Goodwill			$ 695			695			$ 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		100.00%
Businesses acquired, cash consideration		$ 1,309
Goodwill		$ 1,000				1,000			$ 1,000
Expected percent of goodwill deductible for tax purposes		0.00%
Acquired intangible asset, weighted average useful life									6 years 11 months
Cleversafe \| Technology Services & Cloud Platforms
Acquisitions:
Goodwill		$ 590
Cleversafe \| Systems
Acquisitions:
Goodwill		$ 410
The Weather Company \| Subsequent event
Acquisitions:
Businesses acquired, cash consideration	$ 2,000
Truven \| Subsequent event \| Estimated
Acquisitions:
Businesses acquired, cash consideration					$ 2,600
Other Acquisitions
Acquisitions:
Percentage of business acquired										100.00%	100.00%
Goodwill						895			$ 895	$ 442	$ 961
Expected percent of goodwill deductible for tax purposes									7.00%	1.00%	2.00%
Acquired intangible asset, weighted average useful life									6 years 5 months	6 years 10 months	6 years 7 months
Other Acquisitions \| Cognitive Solutions
Acquisitions:
Businesses acquired, number (in entities) \| Acquisition									6	4	7
Goodwill						$ 518			$ 518	$ 311	$ 684
Other Acquisitions \| GBS
Acquisitions:
Businesses acquired, number (in entities) \| Acquisition						2
Goodwill						$ 74			$ 74
Other Acquisitions \| Technology Services & Cloud Platforms
Acquisitions:
Businesses acquired, number (in entities) \| Acquisition								1	4	2
Goodwill						$ 303			$ 303	$ 131	264
Other Acquisitions \| Systems
Acquisitions:
Businesses acquired, number (in entities) \| Acquisition							1
Goodwill											$ 13
AlchemyAPI
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Blekko
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Explorys
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Phytel
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Compose
Acquisitions:
Percentage of business acquired						100.00%			100.00%
StrongLoop
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Clearleap
Acquisitions:
Percentage of business acquired						100.00%			100.00%
IRIS Analytics
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Blue Box
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Gravitant
Acquisitions:
Percentage of business acquired						100.00%			100.00%
Meteorix
Acquisitions:
Percentage of business acquired						100.00%			100.00%