Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Fixed income securities, held-to-maturity - at carrying value	$ 22,700	$ 31,157
Less: allowance for credit losses	0	0
Fixed income securities, held-to-maturity, net of allowance for credit losses	22,700	31,157
Fixed income securities, available-for-sale - at fair value	7,499,197	6,612,107
Financing Receivable, before Allowance for Credit Loss	188,708	149,305
Less: allowance for credit losses	(291)	(116)
Commercial mortgage loans, net of allowance for credit losses	188,417	149,189
Equity securities - at fair value	187,155	162,000
Short-term investments	309,317	440,456
Alternative investments	395,779	371,316
Other investments	91,164	71,244
Total investments (Notes 5 and 7)	8,693,729	7,837,469
Cash	180	26
Restricted cash	13,092	25,183
Accrued investment income	66,339	59,167
Premiums receivable	1,331,979	1,101,787
Less: allowance for credit losses (Note 8)	(18,900)	(16,100)
Premiums receivable, net of allowance for credit losses	1,313,079	1,085,687
Reinsurance recoverable	658,525	784,410
Less: allowance for credit losses (Note 9)	(1,700)	(1,600)
Reinsurance recoverable, net of allowance for credit losses	656,825	782,810
Prepaid reinsurance premiums (Note 9)	203,320	172,371
Current federal income tax (Note 14)	0	3,545
Deferred federal income tax (Note 14)	140,237	172,733
Property and equipment - at cost, net of accumulated depreciation and amortization	83,272	84,306
Deferred policy acquisition costs (Note 2)	424,864	368,624
Goodwill (Note 12)	7,849	7,849
Other assets	199,760	202,491
Total assets	11,802,546	10,802,261
LIABILITIES AND STOCKHOLDERS’ EQUITY
Reserve for loss and loss expense (Note 10)	5,336,911	5,144,821
Unearned premiums	2,330,656	1,992,781
Long-term debt (Note 11)	503,946	504,676
Current federal income tax (Note 14)	6,251	0
Accrued salaries and benefits	122,003	115,185
Other liabilities	548,398	517,234
Total liabilities	8,848,165	8,274,697
Stockholders’ Equity:
Preferred stock of $0 par value per share (Note 17): Authorized shares: 5,000,000; Issued shares: 8,000 with $25,000 liquidation preference per share - 2023 and 2022	200,000	200,000
Common stock of $2 par value per share: Authorized shares: 360,000,000 Issued: 105,223,307 - 2023; 104,847,111 - 2022	210,447	209,694
Additional paid-in capital	522,748	493,488
Retained earnings	3,029,396	2,749,703
Accumulated other comprehensive income (loss) (Note 6)	(373,001)	(498,042)
Treasury stock, at cost (shares: 44,586,870 - 2023; 44,508,211 - 2022)	(635,209)	(627,279)
Total stockholders’ equity	2,954,381	2,527,564
Total liabilities and stockholders’ equity	$ 11,802,546	$ 10,802,261