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Investments (Components Of Net Realized Gains, Excluding OTTI Charges) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Schedule of Available-for-sale and held-to-maturity Securities [Line Items]
HTM securities realized gain	$ 44	$ 3	$ 44	$ 3
HTM fixed income securities losses	0	0	(1)	(1)
Other investments gains	0	0	480	0
Other investments losses	(5)	0	(19)	(4)
Total net realized gains (excluding OTTI charges)	2,951	2,314	5,381	3,203
Proceeds from sale of available for sale securities	123,100	88,700	723,400	105,900
Fixed Income Securities [Member]
Schedule of Available-for-sale and held-to-maturity Securities [Line Items]
AFS securities gains	2,715	365	6,267	985
AFS securities losses	(153)	(5)	(1,740)	(41)
Equity Securities [Member]
Schedule of Available-for-sale and held-to-maturity Securities [Line Items]
AFS securities gains	350	2,171	350	2,501
AFS securities losses	$ 0	$ (220)	$ 0	$ (240)

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
-Section 50
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