Investments (Schedule of Amortized Cost, Unrealized Gains and Losses, and Market Value of Investment Securities) (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Cost	$ 173,228,927	$ 172,587,805
Unrealized Gains	590,938	236,375
Unrealized Losses	(10,000,656)	(13,034,062)
Market Value	163,819,209	159,790,118
Short-Term Investments | Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	1,250,000	1,750,256
Unrealized Gains	0	0
Unrealized Losses	(5,197)	(14,093)
Market Value	1,244,803	1,736,163
Short-Term Investments | Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	1,988,060	5,571,417
Unrealized Gains	0	0
Unrealized Losses	(70,887)	(98,076)
Market Value	1,917,173	5,473,341
Short-Term Investments | Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	4,754,815	4,476,613
Unrealized Gains	0	0
Unrealized Losses	(39,620)	(53,572)
Market Value	4,715,195
Short-Term Investments | Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	3,493,481	5,223,500
Unrealized Gains	0	0
Unrealized Losses	(18,130)	(48,727)
Market Value	3,475,351
Short-Term Investments | Other
Debt Securities, Available-for-sale [Line Items]
Cost	4,671,277	2,347,602
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	4,671,277	2,347,602
Long-Term Investments | Asset Backed Securities
Debt Securities, Available-for-sale [Line Items]
Cost	17,111,473	19,151,229
Unrealized Gains	0	0
Unrealized Losses	(206,537)	(321,533)
Market Value	16,904,936	18,829,696
Long-Term Investments | Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	1,000,000	250,000
Unrealized Gains	0	0
Unrealized Losses	(17,985)	(11,075)
Market Value	982,015	238,925
Long-Term Investments | Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	50,055,216	40,410,206
Unrealized Gains	1,660	0
Unrealized Losses	(3,248,493)	(4,099,729)
Market Value	46,808,383	36,310,477
Long-Term Investments | Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	30,736,849	39,637,461
Unrealized Gains	0	0
Unrealized Losses	(1,567,272)	(3,104,827)
Market Value	29,169,577	36,532,634
Long-Term Investments | Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	57,325,671	53,476,883
Unrealized Gains	336,990	235,713
Unrealized Losses	(4,826,535)	(5,282,430)
Market Value	52,836,126	48,430,166
Long-Term Investments | Common Stock
Debt Securities, Available-for-sale [Line Items]
Cost	842,085	292,638
Unrealized Gains	252,288	662
Unrealized Losses	0	0
Market Value	$ 1,094,373	$ 293,300