Assets and Liabilities Measured at Fair Value (Fair Value Assets and Liabilities Measured at Fair Value on a Recurring and Non-recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Apr. 30, 2011	Apr. 30, 2010
Total gain (loss) on financial instruments	$ (12,698)	$ (15,257)
Mortgage-Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Gain (loss) on investments	207	(10)
Mortgage-Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Total [Member]
Investments	158,177	23,016
Mortgage-Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments	158,177	23,016
Municipal Bonds [Member] \| Fair Value, Measurements, Recurring [Member]
Gain (loss) on investments	405	459
Municipal Bonds [Member] \| Fair Value, Measurements, Recurring [Member] \| Total [Member]
Investments	8,740	8,901
Municipal Bonds [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments	8,740	8,901
Trust Preferred Security [Member] \| Fair Value, Measurements, Recurring [Member]
Gain (loss) on investments		(1,823)
Trust Preferred Security [Member] \| Fair Value, Measurements, Recurring [Member] \| Total [Member]
Investments		31
Trust Preferred Security [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments		31
Fair Value, Measurements, Nonrecurring [Member]
Gain or Loss On Real Estate Owned	(1,920)	(4,430)
Gain (loss) on impaired mortgage loans held for investment	(11,390)	(9,453)
Fair Value, Measurements, Nonrecurring [Member] \| Total [Member]
REO	12,366	16,291
Impaired mortgage loans held for investment	90,628	88,456
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
REO	12,366	16,291
Impaired mortgage loans held for investment	90,628	88,456
Total [Member]
Total financial assets at fair value	269,911	136,695
As a percentage of total assets	5.20%	2.60%
Fair Value, Inputs, Level 2 [Member]
Total financial assets at fair value	166,917	31,948
As a percentage of total assets	3.20%	0.60%
Fair Value, Inputs, Level 3 [Member]
Total financial assets at fair value	$ 102,994	$ 104,747
As a percentage of total assets	2.00%	2.00%

Assets and Liabilities Measured at Fair Value (Fair Value Assets and Liabilities Measured at Fair Value on a Recurring and Non-recurring Basis) (Details) (USD $)
In Thousands, unless otherwise specified

12 Months Ended

Apr. 30, 2011

Apr. 30, 2010

Total gain (loss) on financial instruments

$ (12,698)

$ (15,257)

Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]

Gain (loss) on investments

207

(10)

Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Total [Member]

Investments

158,177

23,016

Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]

Investments

158,177

23,016

Municipal Bonds [Member] | Fair Value, Measurements, Recurring [Member]

Gain (loss) on investments

405

459

Municipal Bonds [Member] | Fair Value, Measurements, Recurring [Member] | Total [Member]

Investments

8,740

8,901

Municipal Bonds [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]

Investments

8,740

8,901

Trust Preferred Security [Member] | Fair Value, Measurements, Recurring [Member]

Gain (loss) on investments

(1,823)

Trust Preferred Security [Member] | Fair Value, Measurements, Recurring [Member] | Total [Member]

Investments

Trust Preferred Security [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]

Investments

Fair Value, Measurements, Nonrecurring [Member]

Gain or Loss On Real Estate Owned

(1,920)

(4,430)

Gain (loss) on impaired mortgage loans held for investment

(11,390)

(9,453)

Fair Value, Measurements, Nonrecurring [Member] | Total [Member]

REO

12,366

16,291

Impaired mortgage loans held for investment

90,628

88,456

Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]

REO

12,366

16,291

Impaired mortgage loans held for investment

90,628

88,456

Total [Member]

Total financial assets at fair value

269,911

136,695

As a percentage of total assets

5.20%

2.60%

Fair Value, Inputs, Level 2 [Member]

Total financial assets at fair value

166,917

31,948

As a percentage of total assets

3.20%

0.60%

Fair Value, Inputs, Level 3 [Member]

Total financial assets at fair value

$ 102,994

$ 104,747

As a percentage of total assets

2.00%

- Definition

The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

+ References+ Details

- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c),9(a))
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (c)-(e)
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 22
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 7

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27405-111563

+ Details

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investment securities as of the balance sheet date which may include marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References+ Details