BUSINESS COMBINATIONS (Estimated Fair Values of Assets Acquired and Liabilities Assumed) (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Jul. 02, 2016	Jun. 30, 2016	Jun. 01, 2016	Dec. 15, 2015	Sep. 30, 2015
Business Acquisition [Line Items]
Goodwill	$ 854,188		$ 588,007			$ 533,179
Association Of Certified Anti-Money Laundering Specialists [Member]
Business Acquisition [Line Items]
Current Assets		$ 25,562
Property and Equipment		432
Other Long-term Assets		3,318
Intangible Assets		88,600
Goodwill		274,672
Total Assets Acquired		392,584
Liabilities Assumed		37,326
Net Assets Acquired		$ 355,258
Faculdade de Imperatriz [Member]
Business Acquisition [Line Items]
Current Assets				$ 1,057
Property and Equipment				291
Intangible Assets				2,652
Goodwill				4,997
Total Assets Acquired				8,997
Liabilities Assumed				2,704
Net Assets Acquired				$ 6,293
Grupo Ibmec Educacional S A [Member]
Business Acquisition [Line Items]
Current Assets					$ 27,615
Property and Equipment					17,968
Other Long-term Assets					2,639
Intangible Assets					60,634
Goodwill					106,529
Total Assets Acquired					215,385
Liabilities Assumed					24,423
Net Assets Acquired					$ 190,962