Reinsurance (Details) (USD $)	9 Months Ended
Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2009
Reinsurance [Abstract]
Reinsurance recoverable on loss reserves	$ 166,874,000	$ 275,290,000	$ 299,239,000	$ 332,227,000
Reinsurance recoverable on loss reserves related to captive agreements	150,000,000	248,000,000
Fair value of trust fund assets under our captive agreements	367,000,000	484,000,000
Trust fund assets transferred to us as a result of captive terminations	39,000,000
Fair value of trust fund assets under captive agreements, no reinsurance recoverable on loss reserves	25,000,000	26,000,000
Unearned premium returned due to termination of reinsurance agreement	$ 7,000,000

The fair value of trust fund assets under the entity's captive agreements that do not have reinsurance recoverable on loss reserves.

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- Definition

The fair value of trust fund assets under the entity's captive agreements.

+ Details

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- Definition

The known and estimated amount recoverable, related to captive agreements, as of the balance sheet date from reinsurers for claims paid or incurred by the ceding insurer and associated claims settlement expenses, including estimated amounts for claims incurred but not reported, and policy benefits, net of any related valuation allowance.

+ Details

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- Definition

The amount of trust fund assets that were transferred to the entity as a result of captive terminations during the period.

+ Details

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- Definition

Amount of premiums written on insurance contracts that have not been earned as of the balance sheet date and returned to the company due to termination of reinsurance agreement.

+ Details

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- Details

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- Definition

The known and estimated amount recoverable as of the balance sheet date from reinsurers for claims paid or incurred by the ceding insurer and associated claims settlement expenses, including estimated amounts for claims incurred but not reported, and policy benefits, net of any related valuation allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.(a),6)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 6

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 113

-Paragraph 14, 16, 27, 113

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6824-158387

+ Details

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