Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Name Regulation S-X (SX)

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 45

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Section S99

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

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-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

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-Publisher SEC

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-Number 210

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Amount of reclassification, impairment, donation, or other change to long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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Property and Equipment (Details) (USD $)	12 Months Ended
Property and Equipment (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment	$ 269,500,000us-gaap_PropertyPlantAndEquipmentGross	$ 480,200,000us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation	(185,200,000)	(278,800,000)
Property and equipment, net	84,328,000us-gaap_PropertyPlantAndEquipmentNet	201,395,000us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense	27,100,000us-gaap_Depreciation	35,600,000us-gaap_Depreciation	27,900,000us-gaap_Depreciation
Land [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment	1,700,000	1,700,000
Leasehold improvements under development [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment	1,500,000	3,900,000
Building and improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment	55,800,000	52,400,000
Furniture, equipment and software [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment	210,500,000	422,200,000
Cognizant Technology Solutions [Member] \| Assets Held-for-sale [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Transfers and Changes	$ (130,200,000)