Fair Value of Financial Instruments (Schedule of Changes in Fair Value Associated With Level 3 Financial Instruments) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2026 USD ($)
Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 4,040
Unrealized gains/(losses)	(534)
Realized losses	(2)
Sales	(3,004)
Net change	(3,540)
Ending Balance	500
Corporate Equity Securities Financial Instruments Owned [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	114
Realized losses	(10)
Sales	(104)
Net change	(114)
Syndicated Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	56,898
Unrealized gains/(losses)	(20)
Purchases	28,105
Redemptions	(9,328)
Net change	18,757
Ending Balance	75,655
Corporate Equity Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	19,446
Unrealized gains/(losses)	(35)
Net change	(35)
Ending Balance	19,411
Auction Rate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	551
Unrealized gains/(losses)	3
Net change	3
Ending Balance	554
Other Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	13,560
Unrealized gains/(losses)	806
Net change	806
Ending Balance	$ 14,366

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