Note 7 - Investments - Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Total	$ 40,127	$ 35,889	$ 35,889
Gross Unrealized Gains	2		67
Gross Unrealized Losses	2,538		290
Fixed maturities, at fair value (amortized cost of $40,127 and $35,889, respectively)	37,591	35,666	35,666
Total, estimated fair value	37,591	35,666	35,666
US Government Agencies Debt Securities [Member]
Total	15,797		16,276
Gross Unrealized Gains	0		31
Gross Unrealized Losses	717		84
Fixed maturities, at fair value (amortized cost of $40,127 and $35,889, respectively)	15,080		16,223
Total, estimated fair value	15,080		16,223
US States and Political Subdivisions Debt Securities [Member]
Total	2,390		1,880
Gross Unrealized Gains	0		3
Gross Unrealized Losses	158		5
Fixed maturities, at fair value (amortized cost of $40,127 and $35,889, respectively)	2,232		1,878
Total, estimated fair value	2,232		1,878
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Total	9,058		7,679
Gross Unrealized Gains	1		18
Gross Unrealized Losses	647		68
Fixed maturities, at fair value (amortized cost of $40,127 and $35,889, respectively)	8,412		7,629
Total, estimated fair value	8,412		7,629
Asset-Backed Securities [Member]
Total	1,682	449
Gross Unrealized Gains	0	0
Gross Unrealized Losses	72	4
Fixed maturities, at fair value (amortized cost of $40,127 and $35,889, respectively)	1,610	445
Total, estimated fair value	1,610	$ 445
Corporate Debt Securities [Member]
Total	11,200		9,605
Gross Unrealized Gains	1		15
Gross Unrealized Losses	944		129
Fixed maturities, at fair value (amortized cost of $40,127 and $35,889, respectively)	10,257		9,491
Total, estimated fair value	$ 10,257		$ 9,491