Segment Reporting (Schedule Of Underwriting Results For Operating Segments To Income (Loss) Before Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Underwriting gain (loss)	$ 28,592	$ 195,688
Net investment income	147,800	140,976
Net realized capital gains (losses)	(210,588)	92,232
Net derivative gain (loss)	(15,373)	3,231
Corporate expenses	(9,833)	(6,652)
Interest, fee and bond issue cost amortization expense	(7,583)	(7,631)
Other income (expense)	23,363	(3,300)
INCOME (LOSS) BEFORE TAXES	$ (43,622)	$ 414,544

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Amount of the cost of borrowed funds accounted for as interest expense.

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The difference between the price paid by the public and the contract price less the related expenses. A broker-dealer may underwrite a security offering by contracting to buy the issue either at a fixed price or a price based on selling the offering on a best-effort basis.

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