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Investments (Net Investment Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Net Investment Income [Line Items]
Net investment income earned	$ 35,534	$ 32,870
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	31,028	30,089
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	1,449	1,207
Short-term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	19	52
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	5,218	3,602
Investment Expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (2,180)	$ (2,080)

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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X

- Details

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