Finance Receivables - Assessment of credit quality by creditworthiness (Details 4) - Finance receivables - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 498,031	$ 482,864	$ 443,083
Finance receivables, gross contract	502,050	487,118
Contracts | Performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	473,446	473,429
Contracts | Non-performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	24,585	9,435
Contracts | Chapter 13 bankrupt accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables, gross contract	4,019	4,254
Direct Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	10,628	10,978	$ 10,912
Finance receivables, gross contract	10,670	11,012
Direct Loans | Performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	10,406	10,899
Direct Loans | Non-performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	222	79
Direct Loans | Chapter 13 bankrupt accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables, gross contract	$ 42	$ 34