Reinsurance Balances Recoverable - Summary of Reinsurance Reserves Recoverable (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Effects of Reinsurance [Line Items]
Outstanding losses	$ 798,798	$ 784,160
IBNR	605,830	448,578
Fair value adjustments	(21,154)	(52,950)
Total reinsurance reserves recoverable	1,383,474	1,179,788
Paid losses recoverable	90,530	151,767
Net	1,474,004	1,331,555
Non-Life Run-Off
Effects of Reinsurance [Line Items]
Outstanding losses	587,164	568,386
IBNR	465,211	278,696
Fair value adjustments	(17,628)	(46,373)
Total reinsurance reserves recoverable	1,034,747	800,709
Paid losses recoverable	72,213	129,750
Net	1,106,960	930,459
Atrium
Effects of Reinsurance [Line Items]
Outstanding losses	6,772	9,582
IBNR	16,581	14,565
Fair value adjustments	2,499	4,131
Total reinsurance reserves recoverable	25,852	28,278
Paid losses recoverable	430	1,289
Net	26,282	29,567
StarStone
Effects of Reinsurance [Line Items]
Outstanding losses	182,076	181,067
IBNR	123,732	154,850
Fair value adjustments	(6,025)	(10,708)
Total reinsurance reserves recoverable	299,783	325,209
Paid losses recoverable	16,568	19,845
Net	316,351	345,054
Life and Annuities
Effects of Reinsurance [Line Items]
Outstanding losses	22,786	25,125
IBNR	306	467
Fair value adjustments	0	0
Total reinsurance reserves recoverable	23,092	25,592
Paid losses recoverable	1,319	883
Net	$ 24,411	$ 26,475

Reinsurance receivables fair value adjustments.

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Estimated amount after valuation allowance of reinsurance recoverables, due from reinsurers for incurred claims not yet reported, and claims settlement expenses.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount after valuation allowance currently billed or billable under reinsurance contracts.

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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.

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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.

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Amount after valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, amounts expected of incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

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