Investment in loan participation.

No definition available.

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- Definition

Mortgage loans maturity date.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Period Type:	instant

- Definition

The cash outflow associated with purchasing loans held for investment purposes during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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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:
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Rego Park II Loan Participation - Additional Information (Detail) - USD ($) $ in Thousands		9 Months Ended
	Jul. 28, 2017	Sep. 30, 2017	Sep. 30, 2016
Investment In Loan Participation [Line Items]
Rego Park II loan participation payment		$ 200,000	$ 0
Participation Agreement [Member] \| Rego Park II [Member]
Investment In Loan Participation [Line Items]
Rego Park II loan participation payment	$ 200,000
Debt Instrument, Description of Variable Rate Basis	LIBOR
Interest rate (in percentage)		2.84%
Loan maturity date	Nov. 30, 2018
Participation Agreement [Member] \| Rego Park II [Member] \| LIBOR [Member]
Investment In Loan Participation [Line Items]
Basis spread over LIBOR	1.60%