Investments (Components Of Net Realized Gains, Excluding OTTI Charges) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Available-for-sale and held-to-maturity Securities [Line Items]
HTM securities realized gain	$ 0	$ 0	$ 44	$ 3
HTM fixed income securities losses	0	0	(1)	(1)
Other investments gains	0	3	480	3
Other investments losses	0	0	(19)	(4)
Total net realized gains (excluding OTTI charges)	6,871	4,030	12,252	7,233
Proceeds from sale of available for sale securities	107,600	27,000	831,000	132,900
Fixed Income Securities [Member]
Schedule of Available-for-sale and held-to-maturity Securities [Line Items]
AFS securities gains	2,070	2,204	8,337	3,189
AFS securities losses	(74)	(40)	(1,814)	(81)
Equity Securities [Member]
Schedule of Available-for-sale and held-to-maturity Securities [Line Items]
AFS securities gains	4,875	1,863	5,225	4,364
AFS securities losses	$ 0	$ 0	$ 0	$ (240)

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This item represents the gross gain realized on the disposal of held-to-maturity securities during the period.

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This item represents the gross profit realized on the sale of other investments.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-Subparagraph (SX 210.7-04.3)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26853-111562

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