Note 6 - Loans (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Financing Receivable, Nonaccrual	$ 0	$ 0
Financing Receivable, Past Due	$ 0	$ 0
Financing Receivable, Modifications, Number of Contracts	0	2
Equity Received from Troubled Debt Restructuring		$ 800
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down		$ 100
Number of Loans Held for Investment	4	5
Financing Receivable, Individually Evaluated for Impairment, Recorded Investment	$ 0	$ 500
Financing Receivable, Individually Evaluated for Impairment, Recorded Impairment	400
Financing Receivable, Individually Evaluated for Impairment	1,000	0
Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring, Premodification		1,900
Financing Receivable, Troubled Debt Restructuring, Postmodification		1,000
Extended Maturity [Member] \| Loans Held for Investment [Member]
Financing Receivable, Troubled Debt Restructuring, Premodification		1,900
Financing Receivable, Troubled Debt Restructuring, Postmodification		1,000
Loans Collateralizing Asset Backed Securities [Member]
Financing Receivable, Collectively Evaluated for Impairment		1,170,200
Financing Receivable, Individually Evaluated for Impairment		1,800
CLO VI Warehouse Portfolio [Member]
Financing Receivable, after Allowance for Credit Loss, Total	0	$ 26,000
Loans Held for Investment [Member]
Financing Receivable, Nonaccrual	0
Financing Receivable, Past Due	$ 0
Financing Receivable, Modifications, Number of Contracts	2	2
Equity Received from Troubled Debt Restructuring	$ 700	$ 800
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	0	$ 100
Loans Held for Investment [Member] \| Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring, Premodification	1,400
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 700

Represents the amount of equity received from troubled debt restructuring.

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The amount of recorded impairment for the period on financing receivables that were individually evaluated for impairment.

+ References

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Represents recorded investment for individually evaluated for impairment for financing receivable.

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The number of loans held for investment by the company.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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- Definition

Amount of financing receivable on nonaccrual status.

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- Definition

Amount of financing receivable past due.

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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