v2.4.1.9

Assets Acquired and Liabilities Assumed and Recognized at Acquisition Dates at Estimated Fair Values (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 9,431,390us-gaap_Goodwill	$ 9,415,295us-gaap_Goodwill	$ 9,212,974us-gaap_Goodwill
Dialysis businesses and other businesses
Business Acquisition [Line Items]
Current assets	1,203us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets / us-gaap_BusinessAcquisitionAxis = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
Property and equipment	8,880us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment / us-gaap_BusinessAcquisitionAxis = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
Amortizable intangible and other long-term assets	3,614us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets / us-gaap_BusinessAcquisitionAxis = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
Goodwill	31,607us-gaap_Goodwill / us-gaap_BusinessAcquisitionAxis = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
Noncontrolling interests assumed	(2,494)us-gaap_BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue / us-gaap_BusinessAcquisitionAxis = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
Liabilities assumed	(1,766)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities / us-gaap_BusinessAcquisitionAxis = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember
Aggregate purchase price	$ 41,044us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedLessNoncontrollingInterest / us-gaap_BusinessAcquisitionAxis = us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember

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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

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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.

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