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Business Combinations (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2010	Sep. 30, 2011
Business Combinations [Abstract]
Gross premiums of excess and surplus renewal book of business purchased	$ 77,000,000
Increase in premiums written including potential impact of renewal book of business purchased	6.00%
Estimated value of business acquisition expected to close		$ 55,000,000

X

- Definition

The total estimated value of an acquisition, including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, and the fair value of the liabilities assumed.

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- Definition

This item represents the gross premiums written related to the excess and surplus renewal book of business purchased

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- Definition

This item represents the increase in net premiums written including the potential impact of the renewal book of business purchased.

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