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	12 Months Ended
	Apr. 30, 2011	Apr. 30, 2010
Portfolio balance	$ 572,974	$ 683,684
Related allowance	92,087	93,535
% of principal	16.10%
% 30+ Days past due	30.20%
Purchased from SCC [Member]
Portfolio balance	357,814
Related allowance	81,396
% of principal	22.70%
% 30+ Days past due	41.70%
All Other [Member]
Portfolio balance	215,160
Related allowance	$ 10,691
% of principal	5.00%
% 30+ Days past due	11.00%