Fair Value Disclosures - Summary of financial instruments not measured at fair value (Details 1) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	$ 37,642	$ 2,626
Finance receivables	202,042	267,101
Repossessed assets:	1,924	2,117
Credit facility	145,000	165,750
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	37,642	2,626
Finance receivables	202,042	266,573
Repossessed assets:	1,924	2,117
Credit facility	145,000	165,750
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	37,642	2,626
Finance receivables	0	0
Repossessed assets:	0	0
Credit facility	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	0	0
Finance receivables	0	0
Repossessed assets:	0	0
Credit facility	145,000	165,750
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	0	0
Finance receivables	202,042	267,101
Repossessed assets:	1,924	2,117
Credit facility	$ 0	$ 0