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Investments (Net Investment Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement [Line Items]
Net investment income earned	$ 35,313	$ 32,457	$ 34,003	$ 32,870	$ 34,593	$ 30,650	$ 34,006	$ 32,628	$ 134,643	$ 131,877	$ 147,443
Fixed Maturity Securities [Member]
Statement [Line Items]
Net investment income earned									121,582	124,687	129,710
Equity Securities, Dividend Income [Member]
Statement [Line Items]
Net investment income earned									6,140	6,215	4,535
Short-term Investments [Member]
Statement [Line Items]
Net investment income earned									117	151	160
Other Investment Portfolio [Member]
Statement [Line Items]
Net investment income earned									15,208	8,996	20,539
Miscellaneous Investment Income [Member]
Statement [Line Items]
Net investment income earned									0	0	133
Investment Expenses [Member]
Statement [Line Items]
Net investment income earned									$ (8,404)	$ (8,172)	$ (7,634)

X

- Definition

The income earned from investments in securities and other investments including dividends, interest, and returns on other investments. This item does not include realized gains (losses).

+ References

No definition available.

+ Details

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- Details

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