Finance Receivables - Assessment of credit quality by creditworthiness (Details 4) - Finance receivables - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 419,827	$ 498,031	$ 482,864
Finance receivables, gross contract	423,900	502,050
Contracts \| Performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	406,159	473,446
Contracts \| Non-performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	13,668	24,585
Contracts \| Chapter 13 bankrupt accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables, gross contract	4,073	4,019
Direct Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	9,908	10,628	$ 10,978
Finance receivables, gross contract	9,964	10,670
Direct Loans \| Performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	9,645	10,406
Direct Loans \| Non-performing accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	263	222
Direct Loans \| Chapter 13 bankrupt accounts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables, gross contract	$ 56	$ 42