Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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

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Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Amount classified as goodwill attributable to disposal group held for sale or disposed of.

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Fair Value Measurements (Assets Held-for-Sale) (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment	$ 1,884,000us-gaap_AssetImpairmentCharges	$ 0us-gaap_AssetImpairmentCharges
Assets held for sale	50,000,000		50,000,000
Liabilities measured on nonrecurring basis	0		0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property and equipment, net	50,000,000		50,000,000
Goodwill allocated to sale of business	0		0
Assets held for sale	50,000,000		50,000,000
Cognizant Technology Solutions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill allocated to sale of business	0		0
Property, Plant and Equipment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment	1,900,000		80,200,000
Property, Plant and Equipment [Member] \| Cognizant Technology Solutions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment	1,900,000		80,200,000
Goodwill [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment	0		7,000,000
Goodwill [Member] \| Cognizant Technology Solutions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment	0		7,000,000
Assets Held-for-sale [Member] \| Cognizant Technology Solutions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment	$ 1,884,000		$ 87,200,000