Finance Receivables - Assessment of credit quality by creditworthiness (Details 3) - Finance receivables - USD ($) $ in Thousands	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2019
Accounts Notes And Loans Receivable [Line Items]
Total	$ 198,007		$ 221,876
Finance receivables	198,168		222,320
Chapter 13 bankruptcy
Accounts Notes And Loans Receivable [Line Items]
Finance receivables	161		444
Direct Loans
Accounts Notes And Loans Receivable [Line Items]
Total	12,720	$ 11,844	9,480
Finance receivables	12,720		9,488
Direct Loans | Chapter 13 bankruptcy
Accounts Notes And Loans Receivable [Line Items]
Finance receivables	0		8
Performing accounts
Accounts Notes And Loans Receivable [Line Items]
Total	192,232		214,767
Performing accounts | Direct Loans
Accounts Notes And Loans Receivable [Line Items]
Total	12,509		9,309
Non-performing accounts
Accounts Notes And Loans Receivable [Line Items]
Total	5,775		7,109
Non-performing accounts | Direct Loans
Accounts Notes And Loans Receivable [Line Items]
Total	211		171
Contract Portfolio
Accounts Notes And Loans Receivable [Line Items]
Total	185,287	$ 207,247	212,396
Finance receivables	185,448		212,832
Contract Portfolio | Chapter 13 bankruptcy
Accounts Notes And Loans Receivable [Line Items]
Finance receivables	161		436
Contract Portfolio | Performing accounts
Accounts Notes And Loans Receivable [Line Items]
Total	179,723		205,458
Contract Portfolio | Non-performing accounts
Accounts Notes And Loans Receivable [Line Items]
Total	$ 5,564		$ 6,938