Note 2 - Summary of Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Dec. 31, 2013
Note 2 - Summary of Significant Accounting Policies (Details) [Line Items]
Number Of Loans On A Nonaccrual Basis	30	31
Principal Value Of Loans On A Nonaccrual Basis	$ 17.3	$ 19.1
Restricted Cash and Cash Equivalents	63.8	44.1
Interest Receivable	29.1	30.2
Deferred Finance Costs, Gross	2.5	4.1
REIT Distribution Percentage	90.00%
Number of Operating Segments	1
Held in Agency IO Portfolio for Trading Purposes [Member]
Note 2 - Summary of Significant Accounting Policies (Details) [Line Items]
Restricted Cash and Cash Equivalents	46.7	30.4
Held by Counterparties as Collateral for Hedging Instruments [Member]
Note 2 - Summary of Significant Accounting Policies (Details) [Line Items]
Restricted Cash and Cash Equivalents	12.7	10.2
Held In Trust Relating To Securitized Debt Transactions [Member]
Note 2 - Summary of Significant Accounting Policies (Details) [Line Items]
Restricted Cash and Cash Equivalents	$ 4.2	$ 3.3
Undistributed [Member]
Note 2 - Summary of Significant Accounting Policies (Details) [Line Items]
REIT Distribution Percentage	85.00%

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The number of loans on a non-accrual basis.

+ References

No definition available.

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- Definition

The principal value of loans on a nonaccrual basis.

+ References

No definition available.

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- Definition

REIT distribution percentage.

+ References

No definition available.

+ Details

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- Definition

For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 8

-Article 5

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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