Property and Equipment, Net - Narrative (Details)  | 
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
| 
 Mar. 31, 2017  
USD ($) 
 | 
 Mar. 31, 2016  
USD ($) 
 | 
 Mar. 31, 2017  
USD ($) 
 | 
 Mar. 31, 2016  
USD ($) 
 | 
 Feb. 02, 2017  
USD ($)  
a 
 | 
|
| Property, Plant and Equipment [Line Items] | |||||
| Gain on sale of real estate | $ 1,396,000 | $ 760,000 | $ 1,832,000 | $ 902,000 | |
| Hendry County, Florida | |||||
| Property, Plant and Equipment [Line Items] | |||||
| Area of land used (in acres) | a | 49 | ||||
| Proceeds from sale of land | $ 2,200,000 | ||||
| Gain on sale of real estate | 1,400,000 | 1,400,000 | |||
| Fort Myers Property, Florida | |||||
| Property, Plant and Equipment [Line Items] | |||||
| Proceeds from sale of land | $ 6,000,000 | $ 6,000,000 | |||
| X | ||||||||||
- Definition Long Lived Assets Held For Sale, Acres Of Land. No definition available. 
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- Definition Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation. No definition available. 
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| X | ||||||||||
- Definition The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
- 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. No definition available. 
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- Details 
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- Details 
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