INVESTMENT DEBT (Schedule of Maturities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Debt premium	$ 15.4	$ 5.3
Long-term debt	3,023.3us-gaap_LongTermDebt	850.8us-gaap_LongTermDebt
Mortgage Loans and Notes Payable [Member]
Debt Instrument [Line Items]
2015	108.8
2016	60.6
2017	142.3
2018	92.5
2019	1,042.8
Thereafter	733.5
Long-term debt, gross	2,180.5
Debt premium	15.4
Long-term debt	$ 2,195.9

Long-term Debt, Gross, Maturities, Repayments of Principal after Year Five

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Long-term Debt, Gross, Maturities, Repayments of Principal in Next Twelve Months

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Long-term Debt, Gross, Maturities, Repayments of Principal in Year Five

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Long-term Debt, Gross, Maturities, Repayments of Principal in Year Four

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Long-term Debt, Gross, Maturities, Repayments of Principal in Year Three

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Long-term Debt, Gross, Maturities, Repayments of Principal in Year Two

+ References

No definition available.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

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

-Publisher SEC

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-Number 210

-Section 02

-Paragraph 20

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

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 45

-Paragraph 1A

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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.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

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