Reinsurance Balances Recoverable - Summary of Provisions for Uncollectible Reinsurance Balances Recoverable by Rating of Reinsurer (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Effects of Reinsurance [Line Items]
Gross	$ 1,324,730	$ 1,383,474
Net	1,402,216	1,474,004
Non-life Run-off
Effects of Reinsurance [Line Items]
Gross	1,609,160	1,684,331
Provisions for Bad Debt	206,944	210,327
Net	$ 1,402,216	$ 1,474,004
Provisions as a % of Gross	12.90%	12.50%
Non-life Run-off \| Reinsurers rated A- or above
Effects of Reinsurance [Line Items]
Gross	$ 1,009,343	$ 1,051,927
Provisions for Bad Debt	44,551	46,969
Net	$ 964,792	$ 1,004,958
Provisions as a % of Gross	4.40%	4.50%
Secured \| Non-life Run-off \| Reinsurers Rated Below A-
Effects of Reinsurance [Line Items]
Gross	$ 366,540	$ 388,399
Provisions for Bad Debt	0	0
Net	$ 366,540	$ 388,399
Provisions as a % of Gross	0.00%	0.00%
Unsecured \| Non-life Run-off \| Reinsurers Rated Below A-
Effects of Reinsurance [Line Items]
Gross	$ 233,277	$ 244,005
Provisions for Bad Debt	162,393	163,358
Net	$ 70,884	$ 80,647
Provisions as a % of Gross	69.60%	66.90%

Weighted Average Provisions For Bad Debt Percentage Of Gross Reinsurance Balances Recoverable

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+ References

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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21409-158489

Reference 3: 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

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Amount of valuation allowance for reinsurance recoverables. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

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Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

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