Realized and Unrealized Investment Gains (Losses) (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	$ (151,990)	$ 76,390	$ (127,454)	$ 188,680
Income tax benefit (expense)	52,370	(28,190)	44,125	(67,536)
Noncontrolling interests	(10)	(19)	12	(37)
Total change in unrealized gains	(99,630)	48,181	(83,317)	121,107
Debt Securities [Member]
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	(147,792)	87,882	(105,312)	179,520
Debt Securities Previously Impaired [Member]
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	15	194	23	753
Equity securities available for sale
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	(6,779)	(17,870)	(13,624)	8,333
Investment funds
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	$ 2,566	$ 6,184	$ (8,541)	$ 74

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=27724398&loc=d3e27357-111563

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