Unpaid Losses and Loss Expenses and Policy Benefits for Life and Annuity Contracts (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Liability for unpaid losses and loss expenses by type
Case reserves	$ 3,716,195	$ 4,236,038
Additional case reserves (ACRs)	190,183	253,890
IBNR reserves	5,158,333	5,255,878
Unpaid losses and loss expenses	$ 9,064,711	$ 9,745,806	$ 10,646,318	$ 10,709,371

Additional Case Reserves are established for particular circumstances where, on the basis of individual loss reports, the Company estimates that the particular loss or collection of losses covered by a treaty may be greater than those advised by the cedant.

No definition available.

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- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a),(b),(c)
-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

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- References

No definition available.

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- Definition

Estimated costs as of the balance sheet date of settling insured claims and costs incurred in the claims settlement process for claims that have not yet been submitted to the insurance company for reimbursement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.W)
-URI http://asc.fasb.org/extlink&oid=27015833&loc=d3e570705-122907

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section W

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- Definition

Costs of settling insured claims and costs incurred in the claims settlement process for the specified year specifically for claims that have already been submitted to the insurance company for reimbursement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

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