Fair value portion of investments accounted under the equity method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 25
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15)
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Investment Securities (Other Long-Term Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Investment securities
Cost	$ 3,958,800
Other Investments	315,800	$ 331,900
Private equity funds
Investment securities
Other Investments	82,100	45,300
Surplus Note
Investment securities
Other Investments	51,500	65,100
Convertible fixed maturity investments
Investment securities
Other Investments	0	5,600
Private equity securities
Investment securities
Other Investments	32,700	8,300
Affordable Housing Development Fund [Member]
Investment securities
Other Investments	14,700	16,800
Partnership investments [Member]
Investment securities
Other Investments	3,800	5,200
Total hedge and private equity funds included in other long-term investments
Investment securities
Other Investments	127,800	178,500
Other Debt Obligations [Member]
Investment securities
Other Investments	3,200	7,100
Fair value measured on a recurring basis \| Level 3 Inputs \| Other long-term investments
Investment securities
Carrying value of investment accounted for using the equity method	$ 3,800	$ 5,200	$ 6,800