Investments, Amortized Cost and Estimated Fair Values of Fixed Maturities (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost and Estimated Fair Values of Fixed Maturities [Abstract]
Held to maturity, carrying value	$ 693,778,523	$ 688,439,360	$ 690,691,000	$ 668,105,000
Held to maturity, allowance for credit loss	1,355,484	0	$ 0	$ 0
Held to maturity, amortized cost	695,134,000
Held to maturity, gross unrealized gains	2,122,000	1,811,000
Held to maturity, gross unrealized losses	76,831,000	92,205,000
Held to maturity, estimated fair value	620,425,000	598,045,000
Total available for sale, amortized cost	589,594,000	571,913,000
Available for sale, gross unrealized gains	454,000	306,000
Available for sale, gross unrealized losses	43,579,000	48,427,000
Available for sale, estimated fair value	546,469,475	523,791,931
U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies [Member]
Amortized Cost and Estimated Fair Values of Fixed Maturities [Abstract]
Held to maturity, carrying value	101,899,000	103,362,000
Held to maturity, allowance for credit loss	62,000
Held to maturity, amortized cost	101,961,000
Held to maturity, gross unrealized gains	0	1,000
Held to maturity, gross unrealized losses	9,660,000	10,566,000
Held to maturity, estimated fair value	92,301,000	92,797,000
Total available for sale, amortized cost	83,666,000	68,538,000
Available for sale, gross unrealized gains	134,000	109,000
Available for sale, gross unrealized losses	4,654,000	5,125,000
Available for sale, estimated fair value	79,146,000	63,522,000
Obligations of States and Political Subdivisions [Member]
Amortized Cost and Estimated Fair Values of Fixed Maturities [Abstract]
Held to maturity, carrying value	382,388,000	382,097,000
Held to maturity, allowance for credit loss	318,000
Held to maturity, amortized cost	382,706,000
Held to maturity, gross unrealized gains	2,105,000	1,810,000
Held to maturity, gross unrealized losses	48,800,000	60,494,000
Held to maturity, estimated fair value	336,011,000	323,413,000
Total available for sale, amortized cost	45,383,000	45,448,000
Available for sale, gross unrealized gains	72,000	34,000
Available for sale, gross unrealized losses	4,105,000	5,326,000
Available for sale, estimated fair value	41,350,000	40,156,000
Corporate Securities [Member]
Amortized Cost and Estimated Fair Values of Fixed Maturities [Abstract]
Held to maturity, carrying value	198,202,000	190,949,000
Held to maturity, allowance for credit loss	968,000
Held to maturity, amortized cost	199,170,000
Held to maturity, gross unrealized gains	17,000	0
Held to maturity, gross unrealized losses	17,854,000	20,510,000
Held to maturity, estimated fair value	181,333,000	170,439,000
Total available for sale, amortized cost	212,358,000	218,041,000
Available for sale, gross unrealized gains	2,000	8,000
Available for sale, gross unrealized losses	14,710,000	15,211,000
Available for sale, estimated fair value	197,650,000	202,838,000
Mortgage-Backed Securities [Member]
Amortized Cost and Estimated Fair Values of Fixed Maturities [Abstract]
Held to maturity, carrying value	11,290,000	12,031,000
Held to maturity, allowance for credit loss	7,000
Held to maturity, amortized cost	11,297,000
Held to maturity, gross unrealized gains	0	0
Held to maturity, gross unrealized losses	517,000	635,000
Held to maturity, estimated fair value	10,780,000	11,396,000
Total available for sale, amortized cost	248,187,000	239,886,000
Available for sale, gross unrealized gains	246,000	155,000
Available for sale, gross unrealized losses	20,110,000	22,765,000
Available for sale, estimated fair value	$ 228,323,000	$ 217,276,000