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Note 10 - Derivative Financial Instruments - Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative financial instruments	$ 1,662	$ 669
TBA and Other Forward MBS [Member] | Long [Member] | Investments -Trading [Member]
Derivative financial instruments	13,717	3,686
TBA and Other Forward MBS [Member] | Short [Member] | Trading Securities Sold, Not Yet Purchased [Member]
Derivative financial instruments	(11,822)	(3,017)
Other Extended Settlement Trade [Member] | Long [Member] | Investments -Trading [Member]
Derivative financial instruments
Other Extended Settlement Trade [Member] | Short [Member] | Trading Securities Sold, Not Yet Purchased [Member]
Derivative financial instruments
Derivatives, Publicity Traded Options [Member] | Short [Member] | Other Investments Sold, Not Yet Purchased [Member]
Derivative financial instruments	$ (233)

X

- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

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Namespace Prefix:
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X

- Details

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X

- Details

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X

- Details

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- Details

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- Details

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- Details

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- Details

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