Allowance For Credit Losses (Reserve Allowance For Various Credit Loss) (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2020 USD ($)
Valuation And Qualifying Accounts [Abstract]
Balance as of March 31, 2020	$ 3,684
Transition adjustment current expected credit losses	4,948
Write-offs against allowance	0
Recoveries	0
Balance as of June 30, 2020	8,632
Trade Receivables
Valuation And Qualifying Accounts [Abstract]
Balance as of March 31, 2020	2,680
Transition adjustment current expected credit losses	43
Write-offs against allowance	0
Recoveries	0
Balance as of June 30, 2020	2,723
Investments, Fixed Maturities
Valuation And Qualifying Accounts [Abstract]
Balance as of March 31, 2020	503
Transition adjustment current expected credit losses	4,905
Write-offs against allowance	0
Recoveries	0
Balance as of June 30, 2020	5,408
Investments, Other
Valuation And Qualifying Accounts [Abstract]
Balance as of March 31, 2020	501
Transition adjustment current expected credit losses	0
Write-offs against allowance	0
Recoveries	0
Balance as of June 30, 2020	$ 501