Note 5 - Investment Securities - Available-for-sale Securities (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Debt Securities, Available-for-sale, Amortized Cost	$ 64,377
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(6,521)
Debt Securities, Available-for-sale	57,856
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain (Loss), before Tax
CLO III Subordinated Notes [Member]
Debt Securities, Available-for-sale, Amortized Cost	12,277
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(1,697)
Debt Securities, Available-for-sale	10,580
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain (Loss), before Tax	1
CLO IV Junior Subordinated Notes [Member]
Debt Securities, Available-for-sale, Amortized Cost	26,174
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(2,877)
Debt Securities, Available-for-sale	23,297
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain (Loss), before Tax	1
CLO V Junior Subordinated Notes [Member]
Debt Securities, Available-for-sale, Amortized Cost	25,926
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(1,947)
Debt Securities, Available-for-sale	23,979
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain (Loss), before Tax	$ 1

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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