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Note 7 - Borrowings - Borrowings (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 15, 2022	Dec. 31, 2021	Mar. 30, 2021	Aug. 13, 2019
Total commitment	$ 483,461		$ 353,000
Balance outstanding	362,711		260,250
Unused commitment	120,750		92,750
Unamortized debt issuance costs attributable to term borrowings	(3,700)		(2,637)
Total borrowings outstanding, net	359,011		257,613
Key Facility [Member]
Total commitment	125,000		125,000
Balance outstanding	67,500		53,500
Unused commitment	57,500		71,500
NYL Facility [Member]
Total commitment	200,000		100,000
Balance outstanding	136,750		78,750
Unused commitment	63,250		21,250
Asset-Backed Notes [Member]
Total commitment	43,461		70,500		$ 160,000
Balance outstanding	43,461		70,500
Unused commitment	0		0
The 2027 Notes [Member]
Total commitment	57,500	$ 50,000	0
Balance outstanding	57,500		0
Unused commitment	0		0
The 2026 Notes [Member]
Total commitment	57,500		57,500	$ 57,500
Balance outstanding	57,500		57,500
Unused commitment	$ 0		$ 0