Derivative Instruments (Narrative) (Details) $ in Millions	Sep. 30, 2016 USD ($)
Real Estate [Member]
Derivative [Line Items]
Derivative loss from industry concentration	$ 15.7
Retirement communities [Member]
Derivative [Line Items]
Derivative loss from industry concentration	3.5
Distribution [Member]
Derivative [Line Items]
Derivative loss from industry concentration	3.4
Swaps with Central Clearing Agency and Dealer Counterparties [Member]
Derivative [Line Items]
Swap Net Liability Position Fair Value	31.3
Investment Securities [Member] \| Swaps with Central Clearing Agency and Dealer Counterparties [Member]
Derivative [Line Items]
Value Of Collateral Posted	5.1
Cash [Member] \| Swaps with Central Clearing Agency and Dealer Counterparties [Member]
Derivative [Line Items]
Value Of Collateral Posted	$ 36.8

The aggregate fair value amounts of interest rate swaps in a net liability position at the end of the reporting period.

No definition available.

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- Definition

The aggregate value of collateral posted for interest rate swaps in a net liability position as of the end of the reporting period.

+ References

No definition available.

+ Details

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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

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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