Mortgage Loans Held For Investment And Related Assets (Schedule Of Allowance For Impaired Loans) (Details) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2013	Apr. 30, 2013	Jul. 31, 2012
Mortgage Loans Held For Investment And Related Assets [Abstract]
Based on collateral value method	$ 4,914	$ 3,762	$ 7,553
Based on discounted cash flow method	4,866	4,924	6,931
Total allowance for loans	$ 9,780	$ 8,686	$ 14,484