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Investments (Net Investment Income) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Net investment income earned	$ 39,345,000	$ 36,545,000	$ 82,818,000	$ 71,251,000
Increase In Net Investment Income Before Tax	2,800,000		11,600,000
Fixed Maturity Securities [Member]
Net investment income earned	32,752,000	32,977,000	65,875,000	66,173,000
Equity Securities [Member]
Net investment income earned	785,000	480,000	1,102,000	932,000
Short-term Investments [Member]
Net investment income earned	33,000	133,000	95,000	233,000
Other Investments [Member]
Net investment income earned	7,922,000	4,884,000	19,588,000	8,816,000
Investment Expenses [Member]
Net investment income earned	$ (2,147,000)	$ (1,929,000)	$ (3,842,000)	$ (4,903,000)

X

- Definition

This item represents the increase (decrease) in income earned from investments in securities and other investments including dividends, interest, and returns on other investments in the current reporting period as compared to the comparable prior year period. This item does not include realized gains (losses).

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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).

+ Details

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