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, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Realized and Unrealized Investment Gains Losses [Line Items]
pre tax realized gain from sale of wholly owned non insurance business	$ 253,100		$ 135,000
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	0	$ 12,515	18,114	$ 12,515
Change in unrealized gains (losses) before income taxes and noncontrolling interests	(72,168)	(7,730)	198,807	(135,184)
Income tax benefit (expense)	24,493	12,229	(64,594)	56,354
Noncontrolling interests	57	94	66	106
Total change in unrealized gains	(47,618)	4,593	134,279	(78,724)
Proceeds from Divestiture of Businesses	118,200
Debt Securities [Member]
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	(45,388)	2,449	169,933	(102,863)
Debt Securities Previously Impaired [Member]
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	(1,406)	50	413	73
Equity securities available for sale
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	(28,517)	(2,353)	12,433	(15,977)
Investment funds
Realized and Unrealized Investment Gains Losses [Line Items]
Change in unrealized gains (losses) before income taxes and noncontrolling interests	$ 3,143	$ (7,876)	$ 16,028	$ (16,417)

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=27724398&loc=SL6284393-111563

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Change in Unrealized Gain/(loss) on Investments, Including Portion Attributable to Noncontrolling Interest

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Change in Unrealized Gain/(loss) on Investments, Including Portion Attributable to Noncontrolling Interest, Net of Tax

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Change in Unrealized Gain/(loss) on Investments, tax

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pre tax realized gain from sale of wholly owned non insurance business

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Realized and Unrealized Investment Gains Losses [Line Items]

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