Liability for Losses and Loss Expenses, Reconciliation of Net Incurred and Paid Claims Development Tables to Liability for Claims and Claim Adjustment Expenses (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of Net Incurred and Paid Claims Development [Abstract]
Net outstanding liabilities	$ 619,994,000
Reinsurance recoverable	427,750,000
Unallocated loss adjustment expenses	73,302,000
Gross liability for unpaid losses and loss expenses	1,121,045,758	$ 1,077,620,301	$ 962,007,437	$ 869,673,849
Personal Automobile [Member]
Reconciliation of Net Incurred and Paid Claims Development [Abstract]
Net outstanding liabilities	97,163,000
Reinsurance recoverable	104,349,000
Homeowners [Member]
Reconciliation of Net Incurred and Paid Claims Development [Abstract]
Net outstanding liabilities	25,905,000
Reinsurance recoverable	14,712,000
Commercial Automobile [Member]
Reconciliation of Net Incurred and Paid Claims Development [Abstract]
Net outstanding liabilities	162,683,000
Reinsurance recoverable	101,574,000
Commercial Multi-Peril [Member]
Reconciliation of Net Incurred and Paid Claims Development [Abstract]
Net outstanding liabilities	189,400,000
Reinsurance recoverable	108,853,000
Workers Compensation [Member]
Reconciliation of Net Incurred and Paid Claims Development [Abstract]
Net outstanding liabilities	114,333,000
Reinsurance recoverable	90,454,000
Other [Member]
Reconciliation of Net Incurred and Paid Claims Development [Abstract]
Net outstanding liabilities	30,510,000
Reinsurance recoverable	$ 7,808,000