DEBT - Schedule of Long-Term Debt Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Unamortized Basis Adj for Terminated Interest Rate Swaps	$ 4.7	$ 5.1
Debt Instrument, Unamortized Discount	(4.2)	(4.3)
Debt Issuance Costs, Net	(18.8)	(19.4)
Fair-value interest rate swaps	(8.4)	(5.2)
Long-Term Debt	2,973.3	2,976.2
Senior Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	3,000.0	3,000.0
Notes 4.90 Percent Due 2019 \| Senior Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 700.0	$ 700.0
Debt Instrument, Interest Rate, Stated Percentage	4.90%	4.90%
Notes 3.00 Percent Due 2020 \| Senior Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 750.0	$ 750.0
Debt Instrument, Interest Rate, Stated Percentage	3.00%	3.00%
Notes 4.125 Percent Due 2025 \| Senior Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 750.0	$ 750.0
Debt Instrument, Interest Rate, Stated Percentage	4.125%	4.125%
Notes 5.90 Percent Due 2039 \| Senior Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 300.0	$ 300.0
Debt Instrument, Interest Rate, Stated Percentage	5.90%	5.90%
Notes 4.600 Percent due 2044 \| Senior Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 500.0	$ 500.0
Debt Instrument, Interest Rate, Stated Percentage	4.60%	4.60%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective interest rate fair value hedge that is amortized upon discontinuation of the interest rate fair value hedge.

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Fair value as of the balance sheet date of all derivative liabilities designated as interest rate fair value hedging instruments.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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