Investments in Unconsolidated Entities - Outstanding Borrowings of Unconsolidated Entities and Equity in Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016	Sep. 30, 2016
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated entities	$ 6,112		$ 6,112		$ 10,470
Equity in income (loss) of unconsolidated entities	33	$ (51)	55	$ 9
Unconsolidated Entities
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated entities	6,112		6,112		10,470
Total equity of unconsolidated entities	15,725		15,725		31,615
Total outstanding borrowings of unconsolidated entities	$ 17,568		$ 17,568		$ 14,702