Income Taxes, Reconciliation of Federal Income Tax Rate (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation [Abstract]
Income before income tax expense	$ 30,338,508	$ 63,272,503	$ 57,081,030
Computed "expected" taxes	6,371,087	13,287,226	11,987,016
Tax-exempt interest	(1,491,154)	(1,468,806)	(1,325,197)
Proration	401,717	395,663	357,044
Dividends received deduction	(115,713)	(113,845)	(1,913,238)
Net operating loss carryback	0	(1,640,084)	0
Tax benefit on exercise of options	(438,850)	(302,901)	(64,765)
Other, net	357,247	299,998	236,676
Pennsylvania income tax, net of federal benefit	0	0	651,750
Income tax expense	$ 5,084,334	$ 10,457,251	$ 9,929,286