Fair Value Measurements - Additional Information (Details) $ in Millions	9 Months Ended
	Jun. 30, 2020 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Ownership percentage	0.13
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Grupo Finmart | Notes Receivable | Discount Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input of note receivable	0.05
Variable Interest Entity, Not Primary Beneficiary
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restructured notes receivable, amount paid by alphacredit	$ 4.0