Mortgage Loans Held For Investment And Related Assets (Schedule Of Portfolio Balance And Related Allowance) (Details) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2013	Apr. 30, 2013	Jul. 31, 2012
Mortgage Loans Held For Investment And Related Assets [Line Items]
Portfolio Balance	$ 322,454	$ 350,235	$ 405,670
Related Allowance	15,514	14,314	22,185
Pooled (less than 60 days past due)
Mortgage Loans Held For Investment And Related Assets [Line Items]
Portfolio Balance	186,082	207,319	238,999
Related Allowance	5,734	5,628	7,701
Individually (TDRs)
Mortgage Loans Held For Investment And Related Assets [Line Items]
Portfolio Balance	50,136	55,061	67,587
Related Allowance	4,866	4,924	6,931
Individually (60 days or more past due)
Mortgage Loans Held For Investment And Related Assets [Line Items]
Portfolio Balance	86,236	87,855	99,084
Related Allowance	$ 4,914	$ 3,762	$ 7,553