Realized and Unrealized Investment Gains (Losses) (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment gains	$ (8,563)	$ (72,168)	$ 50,148	$ 198,807
Income tax benefit (expense)	423	24,493	(23,550)	(64,594)
Noncontrolling interests	5	57	19	66
Total change in unrealized gains	(8,135)	(47,618)	26,617	134,279
Debt securities
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment gains	(10,627)	(45,388)	84,214	169,933
Previously impaired fixed maturity securities
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment gains	61	(1,406)	905	413
Equity securities available for sale
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment gains	(2,126)	(28,517)	(44,812)	12,433
Investment funds
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment gains	$ 4,129	$ 3,143	$ 9,841	$ 16,028

This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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