Reinsurance (Schedule of Premium Receivable Allowance for Credit Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for expected credit losses, beginning of period	$ 22,883	$ 19,823
Provision for expected credit losses	2,335	1,790
Allowance for expected credit losses, end of period	25,218	22,883
Cumulative Effect, Period Of Adoption, Adjustment
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for expected credit losses, beginning of period	$ 0	1,270
Allowance for expected credit losses, end of period		$ 0