Fair Value Measurements - Notes Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes receivable, related party	$ 67,100	$ 67,100
Principal collections on notes receivable	8,200	23,336	$ 0
Discount	3,800	3,800		$ 6,700
Notes receivable, net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset Recorded in Consolidated Balance Sheet	63,277	63,277		83,065
Maximum Exposure to Loss	63,277	63,277		83,065
Prepaid expenses and other current assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset Recorded in Consolidated Balance Sheet	298	298		1,209
Maximum Exposure to Loss	0	0		0
Accounts payable, accrued expenses and other current liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability Recorded in Consolidated Balance Sheet	(310)	(310)		(1,258)
Maximum Exposure to Loss	0	0		0
Disposal Group | Grupo Finmart | Accounts payable, accrued expenses and other current liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum Exposure to Loss	$ 6,200	$ 6,200		$ 25,300