Finance Receivables - Summary of reconciliation of changes in allowance for credit losses on contracts (Details 2) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accounts Notes And Loans Receivable [Line Items]
Provision for credit losses	$ 3,050	$ 4,000	$ 6,350	$ 8,385
Finance receivables
Accounts Notes And Loans Receivable [Line Items]
Balance at beginning of period	11,248	16,112	11,162	16,932
Provision for credit losses	3,050	4,000	6,350	8,385
Charge-offs	(4,215)	(8,322)	(8,705)	(15,014)
Recoveries	1,386	1,712	2,662	3,199
Balance at end of period	11,469	13,502	11,469	13,502
Finance receivables | Contract Portfolio
Accounts Notes And Loans Receivable [Line Items]
Balance at beginning of period	10,651	15,494	10,433	16,575
Provision for credit losses	3,050	3,600	6,350	7,580
Charge-offs	(4,073)	(8,140)	(8,407)	(14,675)
Recoveries	1,349	1,698	2,601	3,172
Balance at end of period	10,977	12,652	10,977	12,652
Finance receivables | Direct Loans
Accounts Notes And Loans Receivable [Line Items]
Balance at beginning of period	597	618	729	357
Provision for credit losses	0	400	0	805
Charge-offs	(142)	(182)	(298)	(339)
Recoveries	37	14	61	27
Balance at end of period	$ 492	$ 850	$ 492	$ 850