Investment Debt (Schedule of Maturities) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Carrying Value	$ 1,628.3	$ 850.8
Mortgage Loans and Notes Payable [Member]
Debt Instrument [Line Items]
2014	26.9
2015	118.7
2015	51.8
2016	146.7
2017	86.7
Thereafter	438.5
Long-term debt gross	869.3
Debt premium	12.9
Carrying Value	$ 882.2

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

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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

+ References

No definition available.

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- Definition

Long-term Debt, Gross, Maturities, Repayments of Principal Remainder of Fiscal Year

+ References

No definition available.

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- Definition

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

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- Definition

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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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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-Name Regulation S-X (SX)

-Number 210

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-Section 02

-Paragraph 20, 22

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