Realized And Unrealized Investment Gains (Losses) on Investments (Realized and Unrealized Investments Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Fixed maturity securities, gains	$ 3,157	$ 7,921	$ 8,403	$ 21,260
Fixed maturity securities, losses	(3,377)	(4,125)	(6,895)	(7,865)
Net realized (losses) gains on investment sales	(6)	119,422	23,339	241,743
Change in unrealized gains (losses)	69,418	(54,652)	111,496	(148,857)
Investment funds	41	(353)	58	(234)
Real estate	3,021	(402)	5,767	7,596
Loans receivable	0	1	(970)	2,059
Other	1,320	1,819	1,028	2,393
Net realized and unrealized gains on investments in earnings before OTTI	73,574	69,631	142,226	118,095
Other-than-temporary impairments	0	0	0	0
Net realized and unrealized gains on investments in earnings	73,574	69,631	142,226	118,095
Income tax expense	(15,451)	(14,623)	(29,867)	(24,800)
After-tax net realized and unrealized gains on investments in earnings	$ 58,123	$ 55,008	$ 112,359	$ 93,295

Amount of gain (loss) on sale or disposal of an equity method investment.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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-Subparagraph (SX 210.5-03(b)(7)(c))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Subparagraph (SX 210.5-03(b)(9)(a))
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Amount of realized and unrealized gain (loss) on investment.

+ References

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Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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Amount of gain (loss) included in earnings for investments classified as other.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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Available for Sale and Held-to-Maturity Realized Gains, Debt Securities, Excluding Other than Temporary Impairments and Allowances

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Available for Sale and Held-to-Maturity Realized Losses, Debt Securities, Excluding Other than Temporary Impairments and Allowances

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Available-for-sale Securities, Gross Realized Gain (Loss), Equity Securities, Excluding Other than Temporary Impairments

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REal Estate Realized Gain (Loss) on Disposal

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Realized Gain (Loss) on Investments, Including Equity Method Investments, Excluding Other than Temporary Impairments and Allowances

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Realized Gain (Loss) on Marketable Securities, Equity Method Investments, and Other Investments, Net of Tax

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Realized Gain (Loss) on Marketable Securities, Equity Method Investments, and Other Investments, Tax

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