Strategic Investments - Additional Information (Details) $ in Thousands, $ in Millions	1 Months Ended		12 Months Ended			104 Months Ended
	Jun. 30, 2018 USD ($) shares	Jun. 30, 2018 AUD ($) shares	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2018 USD ($)
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investment			$ 14,036	$ 0	$ 0
Income (loss) from equity method investments			$ 5,529	4,916	(255)
Cash Converters International Limited
Schedule of Equity Method Investments [Line Items]
Number of common shares owned (shares) | shares			214,183,714
Percentage of common shares owned			34.75%
Payments to acquire equity method investment						$ 96,100
Number of shares acquired (shares) | shares	57,631,230	57,631,230
Value of shares acquired	$ 14,000	$ 39.5
Percentage of ownership increase	3.00%	3.00%
Income (loss) from equity method investments			$ 5,500	4,900	(300)
Dividends received				$ 1,200	2,200
Accumulated undistributed after-tax earnings included in consolidated retained earnings			15,800
United Kingdom | Cash Converters International Limited
Schedule of Equity Method Investments [Line Items]
Impairment of investments			11,700		11,000
Impairment of investments, net of tax			$ 9,200		$ 7,200
Underwritten Placement | Cash Converters International Limited
Schedule of Equity Method Investments [Line Items]
Number of shares acquired (shares) | shares	123,300,000	123,300,000