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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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DEBT - Components of Long-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term debt	$ 3,000.0		$ 1,500.0
Unamortized basis adjustment for settled interest rate swaps	7.0		8.8
Unamortized bond discount	(4.8)		(4.0)
Unamortized debt issuance costs	(21.6)		(11.1)
Fair-value interest rate swaps	0.4		(0.9)
Long-term debt	2,981.0		1,492.8
Notes 4.90 Percent Due 2019
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		4.90%
Notes 4.90 Percent Due 2019 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	700.0		$ 700.0
Debt instrument, interest rate, stated percentage			4.90%
3.000% Notes due 2020 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 750.0		$ 0.0
Debt instrument, interest rate, stated percentage	3.00%		3.00%
4.125% Notes due 2025 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 750.0		$ 0.0
Debt instrument, interest rate, stated percentage	4.125%		4.125%
5.900% Notes due 2039
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		5.90%
5.900% Notes due 2039 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 300.0		$ 300.0
4.600% Notes due 2044 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 500.0		$ 500.0
Debt instrument, interest rate, stated percentage			4.60%