Note 8 - Fair Value Disclosures - Fair Value Measurements on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2026		Dec. 31, 2025
Investments-trading	$ 154,427		$ 140,576
Total other investments, at fair value	61,578		57,258
Trading securities sold, not yet purchased	38,095		36,617
Other investments sold, not yet purchased, at fair value	11		0
Fair Value, Recurring [Member]
Investments-trading	154,427		140,576
Total other investments, at fair value	61,578		57,258
Trading securities sold, not yet purchased	38,095		36,617
Other investments sold, not yet purchased, at fair value	11
Fair Value, Recurring [Member] | Residential Mortgage-Backed Securities [Member]
Investments-trading	3		3
Fair Value, Recurring [Member] | SBA Loans [Member]
Investments-trading	42,286		43,090
Fair Value, Recurring [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Investments-trading	49,194		42,471
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member]
Investments-trading	18,348		17,675
Trading securities sold, not yet purchased	68
Fair Value, Recurring [Member] | Total Investments not Measured at NAV [Member]
Total other investments, at fair value	49,602		44,772
Fair Value, Recurring [Member] | US Treasury Securities [Member]
Investments-trading	21,453
Trading securities sold, not yet purchased			23,802
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investments-trading	147,067		130,207
Trading securities sold, not yet purchased	16,633		12,352
Other investments sold, not yet purchased, at fair value	11
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential Mortgage-Backed Securities [Member]
Investments-trading	3		3
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | SBA Loans [Member]
Investments-trading	42,286		43,090
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Investments-trading	49,194		42,471
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Government Agencies Debt Securities [Member]
Investments-trading	18,348		17,675
Trading securities sold, not yet purchased	68
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Total Investments not Measured at NAV [Member]
Total other investments, at fair value	37,893		24,941
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investments-trading	7,360		10,369
Trading securities sold, not yet purchased	21,462		24,265
Other investments sold, not yet purchased, at fair value	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Total Investments not Measured at NAV [Member]
Total other investments, at fair value	11,709		19,831
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Treasury Securities [Member]
Investments-trading	21,453
Trading securities sold, not yet purchased			23,802
Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Total other investments, at fair value	11,976	[1]	12,486	[2]
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Other investments sold, not yet purchased, at fair value	0
Corporate Bonds and Redeemable Preferred Stock [Member]
Investments-trading	21,354		18,449
Total other investments, at fair value	520		535
Trading securities sold, not yet purchased	2,764		8,107
Corporate Bonds and Redeemable Preferred Stock [Member] | Fair Value, Recurring [Member]
Investments-trading	21,354		18,449
Total other investments, at fair value	520		535
Trading securities sold, not yet purchased	2,764		8,107
Corporate Bonds and Redeemable Preferred Stock [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investments-trading	21,354		18,449
Total other investments, at fair value	520		535
Trading securities sold, not yet purchased	2,764		8,107
Derivative [Member]
Investments-trading	14,975		4,651
Trading securities sold, not yet purchased	13,801		4,245
Derivative [Member] | Fair Value, Recurring [Member]
Investments-trading	14,975		4,651
Trading securities sold, not yet purchased	13,801		4,245
Derivative [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investments-trading	14,975		4,651
Trading securities sold, not yet purchased	13,801		4,245
Equity Securities [Member]
Investments-trading	7,415		10,424
Total other investments, at fair value	13,617		21,457
Trading securities sold, not yet purchased	9		463
Equity Securities [Member] | Fair Value, Recurring [Member]
Investments-trading	7,415		10,424
Total other investments, at fair value	13,617		21,457
Trading securities sold, not yet purchased	9		463
Equity Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investments-trading	55		55
Total other investments, at fair value	1,949		1,626
Trading securities sold, not yet purchased	0
Equity Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investments-trading	7,360		10,369
Total other investments, at fair value	11,668		19,831
Trading securities sold, not yet purchased	9		463
Municipal Bonds [Member]
Investments-trading	852		3,813
Municipal Bonds [Member] | Fair Value, Recurring [Member]
Investments-trading	852		3,813
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investments-trading	852		3,813
Placement Unit and Warrants [Member]
Total other investments, at fair value	33,223		19,997
Placement Unit and Warrants [Member] | Fair Value, Recurring [Member]
Total other investments, at fair value	33,223		19,997
Placement Unit and Warrants [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total other investments, at fair value	33,182		19,997
Placement Unit and Warrants [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total other investments, at fair value	41
Fair Value Receivables [Member]
Notes receivable	2,242		2,783
Fair Value Receivables [Member] | Fair Value, Recurring [Member]
Notes receivable	2,242		2,783
Fair Value Receivables [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Notes receivable	2,242		2,783
Equity Derivatives [Member]
Other investments sold, not yet purchased, at fair value	11		$ 0
Equity Derivatives [Member] | Fair Value, Recurring [Member]
Total other investments, at fair value	11
Equity Derivatives [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total other investments, at fair value	$ 11

[1] As a practical expedient, the Company uses NAV (or its equivalent) to measure the fair value of its investments in U.S. Insurance JV, CREO JV, and CK Capital Value Fund. U.S. Insurance JV invests in U.S. Dollar ("USD") denominated debt issued by small insurance and reinsurance companies. CREO JV invests primarily in multi-family commercial real estate mortgage-backed loans. CK Capital Value Fund invests primarily in office buildings in the Netherlands. According to ASC 820, these investments are not categorized within the valuation hierarchy.

[2] As a practical expedient, the Company uses NAV (or its equivalent) to measure the fair value of its investments in U.S. Insurance JV and CREO JV. U.S. Insurance JV invests in USD denominated debt issued by small insurance and reinsurance companies. CREO JV invests primarily in multi-family commercial real estate mortgage-backed loans. According to ASC 820, these investments are not categorized within the valuation hierarchy.