Mortgage Loans Held For Investment And Related Assets (Schedule Of Mortgage Loans Held For Investment And The Related Allowance) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jul. 31, 2011	Apr. 30, 2011
Portfolio balance	$ 553,991	$ 572,974
Related allowance	91,303	92,087
% of principal	16.50%
% 30+ Days past due	32.70%
Purchased From SCC [Member]
Portfolio balance	346,695
Related allowance	80,640
% of principal	23.30%
% 30+ Days past due	44.80%
All Other [Member]
Portfolio balance	207,296
Related allowance	$ 10,663
% of principal	5.10%
% 30+ Days past due	12.40%