Real Estate - Properties Held For Sale (Details) - Fund II [Member] $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2017 USD ($) property	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($) property
Long Lived Assets Held-for-sale [Line Items]
Number of properties held-for-sale \| property	1		1
Properties held-for-sale	$ 21.5		$ 21.5
Mortgage loans on real estate	25.5		$ 25.5
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Long Lived Assets Held-for-sale [Line Items]
Properties held for sale net income (loss)	$ (0.5)	$ 0.2

Number of Properties Held for Sale

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- Definition

Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Total carrying amount of mortgage loans as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

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