INTANGIBLE ASSETS (Changes in Carrying Amount of Goodwill, by Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018
Goodwill [Line Items]
Goodwill beginning balance	$ 813,887	$ 829,086	$ 838,669
Acquisitions			17,163
Foreign exchange rate changes	(8,602)	9,583	(41,945)
Goodwill ending balance	805,285	838,669	813,887
Medical And Healthcare [Member]
Goodwill [Line Items]
Goodwill beginning balance	310,210	310,210	310,210
Acquisitions			0
Foreign exchange rate changes	0	0	0
Goodwill ending balance	310,210	310,210	310,210
Professional Education [Member]
Goodwill [Line Items]
Goodwill beginning balance	317,699	306,653	306,776
Acquisitions			11,527
Foreign exchange rate changes	(670)	123	(604)
Goodwill ending balance	317,029	306,776	317,699
Technology And Business [Member]
Goodwill [Line Items]
Goodwill beginning balance	185,978	212,223	221,683
Acquisitions			5,636
Foreign exchange rate changes	(7,932)	9,460	(41,341)
Goodwill ending balance	$ 178,046	$ 221,683	$ 185,978

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
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-Topic 350
-SubTopic 20
-Section 50
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Amount before 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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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