Consumer Loans Receivable (Consumer Loan Receivables by Segment and Credit Quality Indicator) (Details) $ in Thousands	6 Months Ended
	Sep. 30, 2017 USD ($) Credit_Quality_Indicator	Apr. 01, 2017 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sensitivity Analysis, Change in Prepayment Rate	$ 1,600
Sensitivity Analysis, Change in Default Rate	4,300
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	99,248	$ 97,148
Chattel Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	57,200	56,575
Chattel Loans Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 1,299	1,509
Chattel Loans Range One [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	0
Chattel Loans Range One [Member] | Maximum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	619
Chattel Loans Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 25,630	25,856
Chattel Loans Range Two [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	620
Chattel Loans Range Two [Member] | Maximum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	719
Chattel Loans Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 29,848	28,726
Chattel Loans Range Three [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	720
Chattel Loans Range Four [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 423	484
Conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	26,421	23,933
Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 252	521
Conforming Mortgages Range One [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	0
Conforming Mortgages Range One [Member] | Maximum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	619
Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 17,166	16,576
Conforming Mortgages Range Two [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	620
Conforming Mortgages Range Two [Member] | Maximum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	719
Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 8,887	6,836
Conforming Mortgages Range Three [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	720
Non-conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 15,616	16,628
Non Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 1,584	1,848
Non Conforming Mortgages Range One [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	0
Non Conforming Mortgages Range One [Member] | Maximum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	619
Non Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 9,128	9,561
Non Conforming Mortgages Range Two [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	620
Non Conforming Mortgages Range Two [Member] | Maximum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	719
Non Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 4,615	4,920
Non Conforming Mortgages Range Three [Member] | Minimum [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Asset class credit quality indicator | Credit_Quality_Indicator	720
Non Conforming Mortgages Range Four [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 289	299
Other Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	11	12
Loans Securitized 2005 [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	25,946	28,040
Loans Securitized 2005 [Member] | Chattel Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	23,167	25,185
Loans Securitized 2005 [Member] | Chattel Loans Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	559	705
Loans Securitized 2005 [Member] | Chattel Loans Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	10,862	11,681
Loans Securitized 2005 [Member] | Chattel Loans Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	11,696	12,748
Loans Securitized 2005 [Member] | Chattel Loans Range Four [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	50	51
Loans Securitized 2005 [Member] | Conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2005 [Member] | Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2005 [Member] | Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2005 [Member] | Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2005 [Member] | Non-conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	2,779	2,855
Loans Securitized 2005 [Member] | Non Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	84	86
Loans Securitized 2005 [Member] | Non Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	1,201	1,242
Loans Securitized 2005 [Member] | Non Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	1,494	1,527
Loans Securitized 2005 [Member] | Other Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2007 [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	22,866	24,574
Loans Securitized 2007 [Member] | Chattel Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	15,058	16,283
Loans Securitized 2007 [Member] | Chattel Loans Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	381	411
Loans Securitized 2007 [Member] | Chattel Loans Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	7,586	8,072
Loans Securitized 2007 [Member] | Chattel Loans Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	7,091	7,800
Loans Securitized 2007 [Member] | Conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2007 [Member] | Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2007 [Member] | Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2007 [Member] | Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Securitized 2007 [Member] | Non-conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	7,808	8,291
Loans Securitized 2007 [Member] | Non Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	421	435
Loans Securitized 2007 [Member] | Non Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	4,670	4,947
Loans Securitized 2007 [Member] | Non Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	2,717	2,909
Loans Securitized 2007 [Member] | Other Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Loans Unsecuritized [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	24,043	19,007
Loans Unsecuritized [Member] | Chattel Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	16,768	11,313
Loans Unsecuritized [Member] | Chattel Loans Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	359	393
Loans Unsecuritized [Member] | Chattel Loans Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	7,024	5,406
Loans Unsecuritized [Member] | Chattel Loans Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	9,012	5,081
Loans Unsecuritized [Member] | Chattel Loans Range Four [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	373	433
Loans Unsecuritized [Member] | Conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	2,235	2,200
Loans Unsecuritized [Member] | Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	159	161
Loans Unsecuritized [Member] | Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	1,746	1,792
Loans Unsecuritized [Member] | Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	330	247
Loans Unsecuritized [Member] | Non-conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	5,029	5,482
Loans Unsecuritized [Member] | Non Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	1,079	1,327
Loans Unsecuritized [Member] | Non Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	3,257	3,372
Loans Unsecuritized [Member] | Non Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	404	484
Loans Unsecuritized [Member] | Non Conforming Mortgages Range Four [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	289	299
Loans Unsecuritized [Member] | Other Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	11	12
Construction Advances [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	10,349	6,957
Construction Advances [Member] | Chattel Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Chattel Loans Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Chattel Loans Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Chattel Loans Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	10,349	6,957
Construction Advances [Member] | Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	261
Construction Advances [Member] | Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	6,344	4,231
Construction Advances [Member] | Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	4,005	2,465
Construction Advances [Member] | Non-conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Non Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Non Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Non Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Construction Advances [Member] | Other Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Consumer Loans Held For Sale [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	16,044	18,570
Consumer Loans Held For Sale [Member] | Chattel Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	2,207	3,794
Consumer Loans Held For Sale [Member] | Chattel Loans Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Consumer Loans Held For Sale [Member] | Chattel Loans Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	158	697
Consumer Loans Held For Sale [Member] | Chattel Loans Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	2,049	3,097
Consumer Loans Held For Sale [Member] | Conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	13,837	14,776
Consumer Loans Held For Sale [Member] | Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	93	99
Consumer Loans Held For Sale [Member] | Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	9,076	10,553
Consumer Loans Held For Sale [Member] | Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	4,552	4,124
Consumer Loans Held For Sale [Member] | Non-conforming Mortgages [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Consumer Loans Held For Sale [Member] | Non Conforming Mortgages Range One [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Consumer Loans Held For Sale [Member] | Non Conforming Mortgages Range Two [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Consumer Loans Held For Sale [Member] | Non Conforming Mortgages Range Three [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	0	0
Consumer Loans Held For Sale [Member] | Other Loans [Member]
Gross Consumer Loans Receivable by Portfolio Segment and Credit Risk Score
Consumer loans receivable	$ 0	$ 0