The Bonds that are subject to interest rate cap agreements.

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
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-Section 50
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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-Topic 860
-SubTopic 20
-Section 50
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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Amount of increase in the fair value of derivatives recognized in the income statement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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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.

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Derivative Instruments and Hedging Activities (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Derivative [Line Items]
Total return swap income	$ 2,184,000	$ 2,538,000	$ 6,682,000	$ 7,653,000
Multifamily Housing Mortgage Revenue Bonds [Member]
Derivative [Line Items]
Bond subject to interest rate caps	256,200,000		256,200,000
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, notional amount	$ 175,000,000		$ 175,000,000
Interest rate	2.30%		2.30%
Aggregate carrying value of the interest rate swap contracts, asset	$ 8,800,000		$ 8,800,000		$ 5,400,000
Designated as Hedging Instrument [Member] \| Interest Rate Cap [Member]
Derivative [Line Items]
Aggregate carrying value of the interest rate swap contracts, liability	0		0		0
Not Designated as Hedging Instrument [Member] \| Interest Rate Cap [Member]
Derivative [Line Items]
Derivative, notional amount	9,900,000		9,900,000
Not Designated as Hedging Instrument [Member] \| Total Return Swap, Callable [Member]
Derivative [Line Items]
Derivative, notional amount	256,200,000		256,200,000
Derivative, fair value, net	$ 0		$ 0		$ 0