Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2021
Reinsurance [Abstract]
Summary of the Effects of Reinsurance	2021 2020WRITTEN Direct $ 71,091,961 $ 58,982,300Reinsurance assumed 78,699 183,204Reinsurance ceded (10,960,325) (10,118,373)Net $ 60,210,335 $ 49,047,131EARNED Direct $ 64,652,638 $ 59,587,071Reinsurance assumed 94,590 182,416Reinsurance ceded (10,854,208) (10,080,285)Net $ 53,893,020 $ 49,689,202LOSS AND SETTLEMENT EXPENSES INCURRED Direct $ 45,685,603 $ 47,067,297Reinsurance assumed 47,536 73,597Reinsurance ceded (11,033,596) (14,578,906)Net $ 34,699,543 $ 32,561,988
Summary of Net Reinsurance Balances Recoverable	Net Reinsurer Ceded A.M. Best Exposure as of Percent of Premiums Percent of(In thousands)Rating December 31, 2021 Total Written TotalPlatinum UnderwritersA+ $ 2,901 18.2% $ 2,317 21.1%Hannover RückversicherungsA+ 2,073 13.0% 1,274 11.6%Aspen Insurance UK LtdA 1,824 11.5% 292 2.7%Partner Reinsurance CompanyA+ 1,514 9.5% 303 2.8%Everest Reinsurance CompanyA+ 1,196 7.5% 271 2.5%Swiss Reinsurance A+ 1,162 7.3% 286 2.6%Endurance ReinsuranceA+ 867 5.4% 306 2.8%General Reinsurance CorporationA++ 774 4.9% 1,537 14.0%Axis Reins CompanyA 742 4.7% 270 2.6%Liberty Mutual Insurance CompanyA 656 4.1% 827 7.5%All other reinsurers including anticipated subrogation 2,206 13.9% 3,277 29.9% $ 15,915 100.0% $ 10,960 100.1%