DEBT - Schedule of Long-Term Debt Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Long-Term Debt
Unamortized Basis Adj for Terminated Interest Rate Swaps	$ 6.6	$ 7.0
Debt Instrument, Unamortized Discount	(4.7)	(4.8)
Debt Issuance Costs, Net	(21.1)	(21.6)
Fair-value interest rate swaps	31.8	0.4
Long-term Debt	3,012.6	2,981.0
Senior Notes
Long-Term Debt
Long-term Debt, Gross	3,000.0	3,000.0
Notes 4.90 Percent Due 2019 \| Senior Notes
Long-Term Debt
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
Long-Term Debt
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
Long-Term Debt
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
Long-Term Debt
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
Long-Term Debt
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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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-Publisher FASB
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-SubTopic 30
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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. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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