Fair Value (Assets Remeasured At Fair Value On Non-Recurring Basis) (Details) (Non-Recurring, USD $) In Thousands, unless otherwise specified	6 Months Ended
	Oct. 31, 2014	Oct. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss, Impaired mortgage loans held for investment	$ (1,440)	$ (2,353)
Total
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired mortgage loans held for investment	62,300	76,148
As a percentage of total assets	2.00%	2.30%
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired mortgage loans held for investment	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]
Impaired mortgage loans held for investment	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]
Impaired mortgage loans held for investment	$ 62,300	$ 76,148
As a percentage of total assets	2.00%	2.30%