Reinsurance Balances Recoverable - Summary of Provisions for Uncollectible Reinsurance Balances Recoverable by Rating of Reinsurer (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Effects of Reinsurance [Line Items]
Gross	$ 1,383,474	$ 1,179,788
Net	1,474,004	1,331,555
Non-life Run-off
Effects of Reinsurance [Line Items]
Gross	1,684,331	1,621,464
Provisions for Bad Debt	210,327	289,909
Net	$ 1,474,004	$ 1,331,555
Provisions as a % of Gross	12.50%	17.90%
Non-life Run-off \| Reinsurers rated A- or above
Effects of Reinsurance [Line Items]
Gross	$ 1,051,927	$ 1,126,944
Provisions for Bad Debt	46,969	80,995
Net	$ 1,004,958	$ 1,045,949
Provisions as a % of Gross	4.50%	7.20%
Secured \| Non-life Run-off \| Reinsurers Rated Below A-
Effects of Reinsurance [Line Items]
Gross	$ 388,399	$ 204,544
Provisions for Bad Debt	0	0
Net	$ 388,399	$ 204,544
Provisions as a % of Gross	0.00%	0.00%
Unsecured \| Non-life Run-off \| Reinsurers Rated Below A-
Effects of Reinsurance [Line Items]
Gross	$ 244,005	$ 289,976
Provisions for Bad Debt	163,358	208,914
Net	$ 80,647	$ 81,062
Provisions as a % of Gross	66.90%	72.00%

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

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+ References

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Amount after valuation allowance recoverable 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 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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