Mortgage Loans Held For Investment And Related Assets (Schedule Of Credit Quality Indicators) (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Apr. 30, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	$ 372,139	$ 429,312
Occupancy Status, Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	256,650
Occupancy Status, Non-Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	115,489
Documentation Level, Full Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	185,004
Documentation Level, Limited Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	23,664
Documentation Level, Stated Income [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	134,485
Documentation Level, No Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	28,986
Internal Risk Rating, High [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	68,645
Internal Risk Rating, Medium [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	143,605
Internal Risk Rating, Low [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	159,889
Purchased From SCC [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	212,250
Purchased From SCC [Member] | Occupancy Status, Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	154,470
Purchased From SCC [Member] | Occupancy Status, Non-Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	57,780
Purchased From SCC [Member] | Documentation Level, Full Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	68,413
Purchased From SCC [Member] | Documentation Level, Limited Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	6,889
Purchased From SCC [Member] | Documentation Level, Stated Income [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	118,100
Purchased From SCC [Member] | Documentation Level, No Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	18,848
Purchased From SCC [Member] | Internal Risk Rating, High [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	68,645
Purchased From SCC [Member] | Internal Risk Rating, Medium [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	143,605
All Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	159,889
All Other [Member] | Occupancy Status, Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	102,180
All Other [Member] | Occupancy Status, Non-Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	57,709
All Other [Member] | Documentation Level, Full Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	116,591
All Other [Member] | Documentation Level, Limited Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	16,775
All Other [Member] | Documentation Level, Stated Income [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	16,385
All Other [Member] | Documentation Level, No Documentation [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	10,138
All Other [Member] | Internal Risk Rating, Low [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Portfolio	$ 159,889