Fair Value Disclosures - Summary of financial instruments not measured at fair value (Details 1) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	$ 24,106	$ 37,642
Finance receivables	190,327	202,042
Repossessed assets:	1,500	1,924
Credit facility	119,450	145,000
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	24,106	37,642
Finance receivables	190,327	202,042
Repossessed assets:	1,500	1,924
Credit facility	119,450	145,000
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	24,106	37,642
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	119,450	145,000
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and restricted cash	0	0
Finance receivables	190,327	202,042
Repossessed assets:	1,500	1,924
Credit facility	$ 0	$ 0