Schedule IV. Reinsurance (Details) - Property and casualty business - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Gross Amount	$ 978,190	$ 1,106,327	$ 1,133,583
Ceded to Other Companies	92,650	84,924	72,023
Assumed From Other Companies	77,283	33,679	25,412
Net Amount	$ 962,823	$ 1,055,082	$ 1,086,972
Percentage of Amount Assumed to Net Earned	8.03%	3.19%	2.34%