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Note 20 - Debt (Details Textual) - USD ($) $ / shares in Units, $ in Thousands										1 Months Ended	12 Months Ended
	Jan. 31, 2022	Dec. 21, 2021	Jun. 21, 2021	Oct. 28, 2020	May 01, 2020	Feb. 03, 2020	Sep. 25, 2019	Sep. 24, 2019	Mar. 10, 2017	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 31, 2020	Jan. 29, 2019	Apr. 25, 2018
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust Net Of Ownership Interest In Trust											$ 49,614
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties, Amount											1,489
Proceeds from Issuance of Long-term Debt, Total											0	$ 2,166	$ 0
Gain (Loss) on Extinguishment of Debt, Total											2,127	(0)	(0)
Long-term Debt, Total											43,394	47,100
Proceeds from Lines of Credit, Total											17,500	17,500	4,777
Amortization of Debt Issuance Costs											471	626	$ 509
ViaNova [Member]
Other Investment Not Readily Marketable, Quoted Value											2,300
Other Investment Not Readily Marketable, Fair Value											2,243
JVB Holdings [Member] \| JVB [Member]
Noncontrolling Interest, Ownership Percentage by Parent				100.00%
Byline Bank [Member] \| JVB [Member] \| Credit Facility [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.50%
Convertible Note 2017 [Member]
Debt Instrument, Face Amount									$ 15,000
Debt Instrument, Interest Rate, Stated Percentage									8.00%
Debt Instrument, Interest Rate In Event of Default									9.00%
Debt Instrument, Convertible, Conversion Price (in dollars per share)									$ 1.45
Paycheck Protection Program CARES Act [Member]
Proceeds from Issuance of Long-term Debt, Total					$ 2,166
Gain (Loss) on Extinguishment of Debt, Total			$ 2,127
Long-term Debt, Total			$ 39
FT Revolver 2019 [Member]
Long-term Debt, Gross										$ 17,500
Proceeds from Lines of Credit, Total										$ 17,500
FT Financial Bank, N.A. [Member]
Line of Credit Facility, Maximum Borrowing Capacity											25,000				$ 7,500
Credit Facility [Member] \| Byline Bank [Member] \| JVB [Member]
Line of Credit Facility, Maximum Borrowing Capacity				$ 25,000
Line of Credit Facility, Commitment Fee Percentage				0.50%
Line of Credit Facility, Commitment Fee Amount		$ 125
Line of Credit Facility, Minimum Request in Reduction of Maximum Borrowing Capacity				$ 1,000
Line of Credit Facility, Reduction in Maximum Borrowing Capacity, Increments After Minimum												500
Debt Instrument, Covenant, Minimum Excess Net Capital				40,000
Credit Facility [Member] \| Byline Bank [Member] \| JVB [Member] \| October 29, 2020 Through December 31, 2021 [Member]
Debt Instrument, Covenant, Minimum Tangible Net Worth				80,000
Credit Facility [Member] \| Byline Bank [Member] \| JVB [Member] \| December 30, 2021 Through December 31, 2022 [Member]
Debt Instrument, Covenant, Minimum Tangible Net Worth				85,000
Credit Facility [Member] \| Byline Bank [Member] \| JVB [Member] \| After December 31, 2022 [Member]
Debt Instrument, Covenant, Minimum Tangible Net Worth				$ 90,000
Credit Facility [Member] \| Byline Bank [Member] \| JVB [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate				6.00%
Debt Instrument, Minimum Interest Rate				7.00%
Contingent Convertible Senior Notes 8% Due 2022 [Member]
Debt Issuance Costs, Gross											1,400
Junior Subordinated Debt [Member]
Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust Net Of Ownership Interest In Trust											$ 49,614
Yield To Maturities											11.32%
Junior Subordinated Debt [Member] \| Sunset Financial Statutory Trust I [Member] \| Alesco Capital Trust I [Member]
Fair Value of Common Securities Variable Interest Entities Trusts											$ 0
Non-convertible Senior Notes [Member] \| Non-convertible Senior Notes 12.00% (2020 Senior Notes) [Member]
Debt Instrument, Face Amount														$ 4,500
Debt Instrument, Interest Rate, Stated Percentage						12.00%
Repayments of Long-term Debt, Total						$ 4,386
Long-term Debt, Gross												2,400
Non-convertible Senior Notes [Member] \| Non-convertible Senior Notes 12.00% (2020 Senior Notes) [Member] \| Subsequent Event [Member]
Debt Instrument, Face Amount	$ 4,500
Non-convertible Senior Notes [Member] \| Non-convertible Senior Notes 12.00% (2020 Senior Notes) [Member] \| JKD Capital Partners I, LTD [Member]
Debt Instrument, Face Amount														2,250
Non-convertible Senior Notes [Member] \| Non-convertible Senior Notes 12.00% (2020 Senior Notes) [Member] \| JKD Capital Partners I, LTD [Member] \| Subsequent Event [Member]
Debt Instrument, Face Amount	$ 2,250
Debt Instrument, Interest Rate, Stated Percentage	10.00%
Debt Instrument, Interest Rate In Event of Default	11.00%
Non-convertible Senior Notes [Member] \| Non-convertible Senior Notes 12.00% (2020 Senior Notes) [Member] \| RN Capital Solutions LLC (RNCS) [Member]
Debt Instrument, Face Amount														$ 2,250
Non-convertible Senior Notes [Member] \| Non-convertible Senior Notes 12.00% (2019 Senior Notes) [Member]
Debt Instrument, Interest Rate, Stated Percentage							12.00%	8.00%
Debt Instrument, Interest Rate In Event of Default							13.00%	9.00%
Credit Facility [Member] \| Byline Bank [Member]
Long-term Debt, Gross											0	0
Credit Facility [Member] \| The 2019 FT Revolver [Member]
Line of Credit Facility, Maximum Borrowing Capacity																$ 25,000
Credit Facility [Member] \| FT LOC 2018 [Member]
Long-term Debt, Gross												17,500
Credit Facility [Member] \| MB Financial Bank, N.A. [Member]
Debt Issuance Costs, Gross											272
Contingent Convertible Senior Notes [Member]
Long-term Debt, Total											14,933	$ 14,599
Contingent Convertible Senior Notes [Member] \| Contingent Convertible Senior Notes 8% Due 2020 [Member]
Debt Issuance Costs, Gross											$ 670