Derivative Instruments (Narrative) (Details) $ in Millions	Dec. 31, 2015 USD ($)
Real Estate And Building Materials [Member]
Derivative [Line Items]
Derivative loss from industry concentration	$ 5.5
Retirement communities [Member]
Derivative [Line Items]
Derivative loss from industry concentration	1.4
Education [Member]
Derivative [Line Items]
Derivative loss from industry concentration	1.3
Swaps with Central Clearing Agency [Member]
Derivative [Line Items]
Swap Net Liability Position Fair Value	11.9
Swaps with Central Clearing Agency [Member] \| Investment Securities [Member]
Derivative [Line Items]
Value Of Collateral Posted	2.4
Swaps with Central Clearing Agency [Member] \| Cash [Member]
Derivative [Line Items]
Value Of Collateral Posted	$ 17.9

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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Period Type:	instant

- 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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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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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Period Type:	instant

- Details

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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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