Note 9 - Financing Arrangements, Portfolio Investments (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2014	Dec. 31, 2013
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Assets Sold under Agreements to Repurchase, Repurchase Liability (in Dollars)	$ 627.9	$ 791.1
Repurchase Agreement Counterparty, Weighted Average Maturity of Agreements	41 days	31 years
Interest Payable (in Dollars)	0.2	0.6
Advance Rate	92.20%	92.20%
Average Haircut	7.80%	7.80%
Repurchase Agreements, Number of Counterparties	11	11
Cash (in Dollars)	28.5
Unencumbered Investment Securities (in Dollars)	208.4
Financing Arrangement Percent	39.60%
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Average Haircut	5.00%	5.00%
Unencumbered Investment Securities (in Dollars)	125.2
Interest-Only-Strip [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Average Haircut	25.00%	25.00%
Collateralized Loan Obligation [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Average Haircut	35.00%	35.00%
Residential Mortgage Backed Securities [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Unencumbered Investment Securities (in Dollars)	127.3
CMBS [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Unencumbered Investment Securities (in Dollars)	46.0
Loans [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Debt, Weighted Average Interest Rate	0.42%	0.49%
Held in Agency IO Portfolio for Trading Purposes [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Unencumbered Investment Securities (in Dollars)	$ 46.7
Amount at Risk In Excess of 5% of Stockholders’ Equity [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Repurchase Agreements, Number of Counterparties	0	0
Weighted Average [Member]
Note 9 - Financing Arrangements, Portfolio Investments (Details) [Line Items]
Average Haircut	7.80%	7.80%

Represents the advance rate of the Company's outstanding balance of repurchase agreements.

No definition available.

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- Definition

Average haircut percentage.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of cash and RMBS stated to be available to meet additional haircut or market valuations as compared to the Company's financing arrangements, portfolio investments.

+ References

No definition available.

+ Details

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- Definition

Number of counterparties the entity has repurchase agreements with.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of unencumbered investment securities available to meet additional haircut or market valuation requirements.

+ References

No definition available.

+ Details

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- Definition

Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph m

-Subparagraph 1

-Article 4

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Subparagraph (SX 210.5-02.1)

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.15(5))

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-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

Weighted average maturity (weighted by amount of the agreement) of repurchase agreements with the counterparty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph m

-Subparagraph 1

-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(m)(1)(i)(B)(iii))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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