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Reinsurance (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	$ 101,352
Letters of credit and funds held	(58,993)
Total unsecured reinsurance recoverables	42,359
Hannover Reinsurance (Ireland) Limited (A+) [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	31,904
Aspen Insurance (Bermuda) Limited (A) [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	14,191
Odyssey America Reinsurance Corporation (A) [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	12,426
Minnesota Workers' Compensation Reinsurance Association (NR) [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	8,641
Clearwater Insurance Company (B+) [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	5,769
Finial Reinsurance Company (A-) [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	4,975
SCOR Reinsurance Company (A) [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	4,904
Other reinsurers [Member]
Schedule of unsecured reinsurance recoverables from reinsurers
Total reinsurance recoverables	$ 18,542

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- Definition

Unsecured reinsurance recoverables.

+ References

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- Definition

Unsecured reinsurance recoverables net.

+ References

No definition available.

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- Definition

Funds held by the ceding insurer on behalf the reinsurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder, which represent an asset for the reinsurer. There is another concept for the corresponding liability of the ceding insurer.

+ 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 210.7-03.2,10)

-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

-Section 03

-Paragraph 2, 10

-Article 7

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