ACQUISITIONS AND DIVESTITURES - Preliminary Purchase Price Allocation and Other Adjustments to Purchase Price Allocations (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 2,419,284us-gaap_Goodwill	$ 2,418,832us-gaap_Goodwill	$ 2,231,582us-gaap_Goodwill
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Fixed assets	(1,477)			1,184
Intangibles	19,791			14,277
Goodwill	41,190			10,850
Accounts receivable	4,217			2,223
Accounts payable	(3,512)			(659)
Net other (liabilities)/ assets	(1,079)			(2,024)
Debt	0			321
Net deferred tax liabilities	(3,377)			(815)
Total purchase price allocation	$ 55,753			$ 25,357

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed 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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