BUSINESS ACQUISITIONS Business Acquisitions in the Aggregate (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Jun. 30, 2015	Dec. 31, 2015	Feb. 19, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Cash consideration					$ 780.8
Other Long-term Debt	$ 715.0			$ 55.5
Revenues	2,368.0	$ 1,793.2
Payments to Acquire Businesses, Net of Cash Acquired	93.3	3,622.2
Goodwill, Acquired During Period	59.4	$ 3,194.6
Business Combination, Acquired Receivables, Fair Value					334.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory					51.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Noncurrent					95.9
Goodwill	6,252.4			$ 6,191.9		$ 3,099.4
Covance [Member]
Business Acquisition [Line Items]
Make-whole payment			$ 37.4
Cash paid for acquisition					4,388.2
Total acquisition consideration (cash and non-cash)					6,150.7
Cash consideration					780.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent					879.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt					250.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable					190.8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities					306.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue					168.0
Revenues	2,146.4
Business Combination, Acquired Receivables, Fair Value					334.8
Unbilled Receivables, Current					138.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory					51.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Noncurrent					34.4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets					12.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets					8,054.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other					109.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities					1,904.0
Excluding Covance [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	93.3
Finite-lived Intangible Assets Acquired	37.3
Goodwill, Acquired During Period	$ 59.4
Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	27 years
Customer Relationships [Member] | Covance [Member]
Business Acquisition [Line Items]
Prepaid expenses and other					347.9
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					1,018.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					1,830.3
Customer Relationships [Member] | Covance, Inc. [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	$ (86.9)
Trademarks and Trade Names [Member] | Covance [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	15 years
Trademarks and Trade Names [Member] | Covance, Inc. [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	$ (18.9)
Trade Names [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					270.5
Use Rights [Member] | Covance [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	8 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					0.0
Use Rights [Member] | Covance, Inc. [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	$ (4.9)
Software and Software Development Costs [Member] | Covance [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					74.5
Software and Software Development Costs [Member] | Covance, Inc. [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	$ 74.5
Off-Market Favorable Lease [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					5.5
Off-Market Favorable Lease [Member] | Covance, Inc. [Member]
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	$ 5.5
Scenario, Previously Reported [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent					730.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets					7,849.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other					78.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities					1,698.3
Scenario, Previously Reported [Member] | Customer Relationships [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					844.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					1,917.2
Scenario, Previously Reported [Member] | Trade Names [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					289.4
Scenario, Previously Reported [Member] | Use Rights [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					4.9
Scenario, Previously Reported [Member] | Software and Software Development Costs [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					0.0
Scenario, Previously Reported [Member] | Off-Market Favorable Lease [Member] | Covance [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					$ 0.0