Fair Value Of Financial Instruments (Schedule Of Changes In Fair Value Associated With Level 3 Financial Instruments) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 1,203	$ 1,498
Realized gains/(losses)	97	1,397
Redemptions	(165)	(1,760)
Net change	(68)	(363)
Ending Balance	1,135	1,135
Syndicated Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	65,713	82,964
Unrealized gains/(losses)	146	1,694
Realized gains/(losses)	(1,460)	(3,252)
Purchases	19,118	47,546
Sales	(16,866)	(49,810)
Redemptions	(8,126)	(20,617)
Net change	(7,188)	(24,439)
Ending Balance	58,525	58,525
Corporate Equity Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	11,878	11,878
Net change	0	0
Ending Balance	11,878	11,878
Auction Rate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	739	783
Unrealized gains/(losses)	(1)	(45)
Net change	(1)	(45)
Ending Balance	738	738
Other Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	39,349	39,467
Unrealized gains/(losses)	(2)	(120)
Net change	(2)	(120)
Ending Balance	$ 39,347	$ 39,347