Fair Value Measurement (Assets Remeasured At Fair Value On Non-Recurring Basis) (Details) (Non-Recurring, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2013	Apr. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss, REO	$ (431)	$ (693)
Loss, Impaired mortgage loans held for investment	(10,663)	(10,235)
Total, Gain (loss) on financial instruments	(11,094)	(10,928)
Total
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
REO	14,806	15,870
Impaired mortgage loans held for investment	84,708	99,974
Total financial assets at fair value	99,514	115,844
As a percentage of total assets	2.20%	2.50%
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
REO	0	0
Impaired mortgage loans held for investment	0	0
Total financial assets at fair value	0	0
As a percentage of total assets	0.00%	0.00%
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
REO	0	0
Impaired mortgage loans held for investment	0	0
Total financial assets at fair value	0	0
As a percentage of total assets	0.00%	0.00%
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
REO	14,806	15,870
Impaired mortgage loans held for investment	84,708	99,974
Total financial assets at fair value	$ 99,514	$ 115,844
As a percentage of total assets	2.20%	2.50%