Allowance For Credit Losses (Reserve Allowance For Various Credit Loss) (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2021 USD ($)
Valuation And Qualifying Accounts [Abstract]
March 31, 2021	$ 4,656
Transition adjustment current expected credit losses	(566)
Write-offs against allowance	0
Recoveries	0
June 30, 2021	4,090
Trade Receivables
Valuation And Qualifying Accounts [Abstract]
March 31, 2021	2,835
Transition adjustment current expected credit losses	(291)
Write-offs against allowance	0
Recoveries	0
June 30, 2021	2,544
Investments, Fixed Maturities
Valuation And Qualifying Accounts [Abstract]
March 31, 2021	1,320
Transition adjustment current expected credit losses	(279)
Write-offs against allowance	0
Recoveries	0
June 30, 2021	1,041
Investments, Other
Valuation And Qualifying Accounts [Abstract]
March 31, 2021	501
Transition adjustment current expected credit losses	4
Write-offs against allowance	0
Recoveries	0
June 30, 2021	$ 505