Liability for Losses and Loss Expenses, Summary of Insurance Subsidiaries' Liability for Losses and Loss Expenses (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Liability for Claims and Claims Adjustment Expense [Abstract]
Balance at January 1	$ 962,007,437	$ 869,673,849	$ 814,665,224
Less reinsurance recoverable	(404,818,480)	(362,768,427)	(339,267,525)
Net balance at January 1	557,188,957	506,905,422	475,397,699
Incurred related to:
Current year	551,917,571	472,709,060	519,319,941
Prior years	(31,208,029)	(12,944,767)	(12,932,277)
Total incurred	520,709,542	459,764,293	506,387,664
Paid related to:
Current year	269,316,762	236,984,291	278,923,614
Prior years	182,222,742	172,496,467	195,956,327
Total paid	451,539,504	409,480,758	474,879,941
Net balance at end of period	626,358,995	557,188,957	506,905,422	$ 475,397,699
Plus reinsurance recoverable	451,261,306	404,818,480	362,768,427	339,267,525
Balance at end of period	$ 1,077,620,301	$ 962,007,437	$ 869,673,849	$ 814,665,224
Percentage of development		5.60%	2.60%	2.70%