Note Receivable Backed by Real Estate - Additional information (Detail) - USD ($) $ in Thousands	Feb. 28, 2015	Sep. 30, 2015
Loans And Leases Receivable [Line Items]
Note received backed by real estate		$ 197,500
Dispositions to Third Parties [Member]
Loans And Leases Receivable [Line Items]
Note received backed by real estate	$ 197,500
Interest rate on Note receivable	2.00%

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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