Segment Reporting (Schedule Of Underwriting Results For Operating Segments To Income (Loss) Before Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting [Abstract]
Underwriting gain (loss)	$ 132,275	$ (411,152)	$ 240,033	$ (342,205)
Net investment income	90,709	72,070	175,243	141,979
Net realized capital gains (losses)	142,563	(42,271)	277,619	(102,472)
Corporate expense	(2,519)	(1,513)	(4,170)	(5,109)
Interest, fee and bond issue cost amortization expense	(9,684)	(7,623)	(19,512)	(14,936)
Other income (expense)	(3,812)	77,682	(5,026)	2,805
INCOME (LOSS) BEFORE TAXES	$ 349,532	$ (312,807)	$ 664,187	$ (319,938)

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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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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