Investments in Unconsolidated Entities and Marketable Securities - Narrative (Details) - USD ($) |
12 Months Ended | ||
---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2016 |
|
Schedule of Equity Method Investments [Line Items] | |||
Impairment of unconsolidated entity investment | $ (341,000) | $ 0 | $ 0 |
Financial Guarantee | |||
Schedule of Equity Method Investments [Line Items] | |||
Outstanding guarantees | $ 0 | $ 0 |