Customer Banking Deposits (Components of Banking Deposits) (Details) (USD $)	12 Months Ended
	Apr. 30, 2011	Apr. 30, 2010
Customer Banking Deposits
Money-market deposits, outstanding balance	$ 164,734,000	$ 195,220,000
Savings deposits, outstanding balance	11,030,000	12,460,000
Interest-bearing checking deposits, outstanding balance	6,947,000	24,190,000
Non-interest-bearing checking deposits, outstanding balance	279,296,000	200,096,000
Checking deposits, outstanding balance	286,243,000	224,286,000
Due in one year, outstanding balance	49,003,000	60,349,000
IRAs, outstanding balance	341,210,000	360,240,000
IRAs and other time deposits, outstanding balance	390,213,000	420,589,000
Deposits, Total	852,220,000	852,555,000
Money-market deposits, interest expense	2,168,000	1,871,000
Savings deposits, interest expense	107,000	128,000
Interest-bearing checking deposits, interest expense	94,000	83,000
Checking deposits, interest expense	94,000	83,000
IRAs and other time deposits, interest expense	6,119,000	8,092,000
Interest Expense, Deposits, Total	8,488,000	10,174,000
Due in two years	7,939,000	12,479,000
Due in three years	3,717,000	6,079,000
Due in four years	16,000	3,105,000
Due in five years	6,000	1,000
Long-term deposits	11,678,000	21,664,000
Accrued interest on deposits	$ 200,000	$ 200,000