Validus 10-K 23 Feb 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Feb. 22, 2017	Jun. 30, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	VALIDUS HOLDINGS LTD
Entity Central Index Key	1,348,259
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Amendment Flag	false
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		79,132,252
Entity Public Float			$ 3,285.5

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets
Fixed maturities trading, at fair value (amortized cost: 2016—$5,584,599; 2015—$5,556,900)	$ 5,543,030	$ 5,510,331
Short-term investments trading, at fair value (amortized cost: 2016—$2,796,358; 2015—$1,941,615)	2,796,170	1,941,635
Other investments, at fair value (cost: 2016—$380,130; 2015—$315,963)	405,712	336,856
Investments in investment affiliates, equity method (cost: 2016—$84,840; 2015—$69,794)	100,431	87,673
Cash and cash equivalents	419,976	723,109
Restricted cash	70,956	73,270
Total investments and cash	9,336,275	8,672,874
Investment in operating affiliate, equity method (cost: 2016—$nil; 2015—$392)	0	392
Premiums receivable	725,390	658,682
Deferred acquisition costs	209,227	181,002
Prepaid reinsurance premiums	77,996	77,992
Securities lending collateral	9,779	4,863
Loss reserves recoverable	430,421	350,586
Paid losses recoverable	35,247	23,071
Income taxes receivable	4,870	16,228
Deferred tax asset	43,529	21,661
Receivable for investments sold	3,901	39,766
Intangible assets	115,592	121,258
Goodwill	196,758	196,758
Accrued investment income	26,488	23,897
Other assets	134,282	126,782
Total assets	11,349,755	10,515,812
Liabilities
Reserve for losses and loss expenses	2,995,195	2,996,567
Unearned premiums	1,076,049	966,210
Reinsurance balances payable	54,781	75,380
Securities lending payable	10,245	5,329
Deferred tax liability	3,331	3,847
Payable for investments purchased	29,447	77,475
Accounts payable and accrued expenses	587,648	627,331
Notes payable to AlphaCat investors	278,202	75,493
Senior notes payable	245,362	245,161
Debentures payable	537,226	537,668
Total liabilities	5,817,486	5,610,461
Commitments and contingent liabilities
Redeemable noncontrolling interests	1,528,001	1,111,714
Shareholders' equity
Preferred shares (Issued and Outstanding: 2016—6,000; 2015—nil)	150,000	0
Common shares (Issued: 2016—161,279,976; 2015—160,570,772; Outstanding: 2016—79,132,252; 2015—82,900,617)	28,224	28,100
Treasury shares (2016—82,147,724; 2015—77,670,155)	(14,376)	(13,592)
Additional paid-in-capital	821,023	1,002,980
Accumulated other comprehensive loss	(23,216)	(12,569)
Retained earnings	2,876,636	2,634,056
Total shareholders' equity available to Validus	3,838,291	3,638,975
Noncontrolling interests	165,977	154,662
Total shareholders' equity	4,004,268	3,793,637
Total liabilities, noncontrolling interests and shareholders’ equity	$ 11,349,755	$ 10,515,812

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets
Fixed maturities, at amortized cost	$ 5,584,599	$ 5,556,900
Short-term investments, at amortized cost	2,796,358	1,941,615
Other investments, at amortized cost	380,130	315,963
Investments in investment affiliates, at cost	84,840	69,794
Investments in operating affiliates, at cost	$ 0	$ 392
Shareholders' equity
Preferred Stock, Shares Issued	6,000	0
Preferred Stock, Shares Outstanding	6,000	0
Common shares, par value	$ 0.175	$ 0.175
Common shares, shares issued	161,279,976	160,570,772
Common shares, shares outstanding	79,132,252	82,900,617
Treasury stock, common shares	82,147,724	77,670,155

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues
Gross premiums written	$ 2,648,705	$ 2,557,506	$ 2,358,865
Reinsurance premiums ceded	(289,705)	(328,681)	(313,208)
Net premiums written	2,359,000	2,228,825	2,045,657
Change in unearned premiums	(109,835)	18,064	(52,602)
Net premiums earned	2,249,165	2,246,889	1,993,055
Net investment income	150,385	127,824	100,086
Net realized gains on investments	15,757	2,298	14,917
Change in net unrealized gains (losses) on investments	16,871	(32,395)	(2,842)
(Loss) income from investment affiliates	(2,083)	4,281	8,411
Other insurance related income and other income	2,195	5,111	1,229
Foreign exchange gains (losses)	10,864	(8,731)	(12,181)
Total revenues	2,443,154	2,345,277	2,102,675
Expenses
Losses and loss expenses	1,065,097	977,833	765,015
Policy acquisition costs	449,482	410,058	339,467
General and administrative expenses	336,294	363,709	329,362
Share compensation expenses	42,907	38,341	33,073
Finance expenses	58,520	74,742	68,324
Transaction expenses	0	0	8,096	[1]
Total expenses	1,952,300	1,864,683	1,543,337
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors	490,854	480,594	559,338
Tax benefit (expense)	19,729	(6,376)	(155)
Loss from operating affiliate	(23)	(3,949)	(4,340)
(Income) attributable to AlphaCat investors	(23,358)	(2,412)	0
Net income	487,202	467,857	554,843
Net (income) attributable to noncontrolling interests	(123,363)	(92,964)	(74,880)
Net income available to Validus	363,839	374,893	479,963
Dividends on preferred shares	(4,455)	0	0
Net income available to Validus common shareholders	359,384	374,893	479,963
Other comprehensive (loss) income:
Change in foreign currency translation adjustments	(10,440)	(3,716)	(7,501)
Change in minimum pension liability, net of tax	(484)	544	(210)
Change in fair value of cash flow hedge	277	(841)	(228)
Other comprehensive (loss), net of tax	(10,647)	(4,013)	(7,939)
Comprehensive (income) attributable to noncontrolling interests	(123,363)	(92,964)	(74,880)
Comprehensive income available to Validus	$ 353,192	$ 370,880	$ 472,024
Earnings per share
Basic earnings per share available to common shareholders	$ 4.43	$ 4.47	$ 5.24
Earnings per diluted share available to common shareholders	4.36	4.34	5.07
Cash dividends declared per share	$ 1.40	$ 1.28	$ 1.20
Weighted average number of common shares and common share equivalents outstanding
Basic (shares)	81,041,974	83,107,236	90,354,745
Diluted (shares)	82,359,460	86,426,760	94,690,271
[1]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred shares	Common shares	Treasury shares	Additional paid-in capital	Accumulated other comprehensive loss	Retained earnings
Total shareholders' equity						$ (617)
Balance - Beginning of period at Dec. 31, 2013		$ 0	$ 27,036	$ (10,228)	$ 1,677,894	(617)	$ 2,010,009
Preferred shares issued		0
Common shares issued, net			186		5,161
Offering expenses on preferred shares					0
Repurchase of common shares				(2,317)	(508,635)
Share compensation expenses					33,073
Other comprehensive loss	$ (7,939)					(7,939)
Net income	554,843						554,843
Net (income) attributable to noncontrolling interests	(74,880)						(74,880)
Dividends on common shares							(117,000)
Dividends on preferred shares							0
Balance - End of period at Dec. 31, 2014	3,586,586	0	27,222	(12,545)	1,207,493	(8,556)	2,372,972
Noncontrolling interests	292,274
Total shareholders' equity	3,878,860					(8,556)
Preferred shares issued		0
Common shares issued, net			878		16,529
Offering expenses on preferred shares					0
Repurchase of common shares				(1,047)	(259,383)
Share compensation expenses					38,341
Other comprehensive loss	(4,013)					(4,013)
Net income	467,857						467,857
Net (income) attributable to noncontrolling interests	(92,964)						(92,964)
Dividends on common shares							(113,809)
Dividends on preferred shares							0
Balance - End of period at Dec. 31, 2015	3,638,975	0	28,100	(13,592)	1,002,980	(12,569)	2,634,056
Noncontrolling interests	154,662
Total shareholders' equity	3,793,637					(12,569)
Preferred shares issued		150,000
Common shares issued, net			124		(7,825)
Offering expenses on preferred shares					(5,148)
Repurchase of common shares				(784)	(211,891)
Share compensation expenses					42,907
Other comprehensive loss	(10,647)					(10,647)
Net income	487,202						487,202
Net (income) attributable to noncontrolling interests	(123,363)						(123,363)
Dividends on common shares							(116,804)
Dividends on preferred shares							(4,455)
Balance - End of period at Dec. 31, 2016	3,838,291	$ 150,000	$ 28,224	$ (14,376)	$ 821,023	(23,216)	$ 2,876,636
Noncontrolling interests	165,977
Total shareholders' equity	$ 4,004,268					$ (23,216)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows provided by (used in) operating activities
Net income	$ 487,202	$ 467,857	$ 554,843
Adjustments to reconcile net income to cash provided by operating activities:
Share compensation expenses	42,907	38,341	33,073
Gain on sale of subsidiary	0	0	(709)
Amortization of discount on senior notes	108	108	108
Loss (income) from investment and operating affiliates	2,106	(332)	(4,071)
Net realized and change in net unrealized (gains) losses on investments	(32,628)	30,097	(12,075)
Amortization of intangible assets	5,666	5,666	4,538
Foreign exchange losses included in net income	3,043	18,907	23,591
Amortization of premium on fixed maturity investments	17,961	23,075	19,107
Change in operational balance sheet items:
Premiums receivable	(76,659)	44,154	22,034
Deferred acquisition costs	(28,225)	(19,980)	(27,131)
Prepaid reinsurance premiums	(4)	4,955	34,443
Loss reserves recoverable	(85,264)	24,659	81,824
Paid losses recoverable	(11,932)	15,111	43,580
Reserve for losses and loss expenses	37,042	(231,345)	(404,280)
Unearned premiums	109,839	(23,019)	18,161
Reinsurance balances payable	(18,487)	(52,785)	(32,262)
Other operational balance sheet items, net	(42,472)	(10,963)	(14,613)
Net cash provided by operating activities	410,203	334,506	340,161
Cash flows provided by (used in) investing activities
Proceeds on sales of fixed maturity investments	2,671,226	3,842,408	4,756,555
Proceeds on maturities of fixed maturity investments	349,722	332,410	554,619
Purchases of fixed maturity investments	(3,074,703)	(4,225,031)	(4,391,814)
Purchases of short-term investments, net	(856,021)	(436,690)	(329,301)
Purchases of other investments, net	(64,943)	(5,988)	(143,597)
(Increase) decrease in securities lending collateral	(4,916)	(4,393)	2,922
Distributions from operating affiliates	369	46,603	0
Investments in investment affiliates, net	(14,841)	(19,886)	(12,468)
Decrease in restricted cash	2,314	99,733	27,489
Proceeds on sale of subsidiary, net of cash	0	0	16,459
Purchase of subsidiary, net of cash	0	0	(643,545)
Net cash used in investing activities	(991,793)	(370,834)	(162,681)
Cash flows provided by (used in) financing activities
Net proceeds on issuance of notes payable to AlphaCat investors	296,325	75,493	0
Net proceeds on issuance of preferred shares	144,852	0	0
(Redemption) issuance of common shares, net	(7,701)	17,407	5,347
Purchases of common shares under share repurchase program	(212,675)	(260,430)	(510,952)
Dividends paid on preferred shares	(4,455)	0	0
Dividends paid on common shares	(115,625)	(112,967)	(117,043)
Increase (decrease) in securities lending payable	4,916	4,393	(2,922)
Third party investments in redeemable noncontrolling interests	393,450	499,200	300,200
Third party redemptions of redeemable noncontrolling interests	(17,285)	(86,933)	(13,192)
Third party investments in noncontrolling interests	171,674	9,600	117,243
Third party distributions of noncontrolling interests	(127,103)	(168,758)	(237,183)
Third party subscriptions (deployed) received on AlphaCat Funds and Sidecars	(225,284)	249,636	127,400
Net cash provided by (used in) financing activities	301,089	226,641	(331,102)
Effect of foreign currency rate changes on cash and cash equivalents	(22,632)	(17,605)	(25,310)
Net (decrease) increase in cash and cash equivalents	(303,133)	172,708	(178,932)
Cash and cash equivalents - beginning of year	723,109	550,401	729,333
Cash and cash equivalents - end of year	419,976	723,109	550,401
Supplemental disclosure of cash flow information:
Taxes paid during the year	6,034	16,050	42,689
Interest paid during the year	$ 54,638	$ 55,047	$ 54,526

Nature of the business

Nature of the business	12 Months Ended
	Dec. 31, 2016
Nature Of Business [Abstract]
Nature of the business	Nature of the business Validus Holdings, Ltd. (together with its wholly and majority owned subsidiaries, the “Company”) was incorporated under the laws of Bermuda on October 19, 2005. The Company provides reinsurance coverage, insurance coverage and insurance linked securities (“ILS”) management through four distinct global operating segments, Validus Re, Talbot, Western World, and AlphaCat. Validus Re is a global reinsurance segment focused primarily on treaty reinsurance. Talbot is a specialty insurance segment, primarily operating within the Lloyd’s insurance market through Syndicate 1183. Western World is a U.S. based specialty excess and surplus lines insurance segment operating within the U.S. commercial market. AlphaCat is a Bermuda based investment adviser, managing capital for third parties and the Company in ILS and other property catastrophe and specialty reinsurance investments.

Basis of preparation and consol

Basis of preparation and consolidation	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of preparation and consolidation	Basis of preparation and consolidation These Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The Company consolidates in these Consolidated Financial Statements the results of operations and financial position of all voting interest entities (“VOE”) in which the Company has a controlling financial interest and all variable interest entities (“VIE”) in which the Company is considered to be the primary beneficiary. The consolidation assessment, including the determination as to whether an entity qualifies as a VIE or VOE, depends on the facts and circumstances surrounding each entity. All significant intercompany accounts and transactions have been eliminated. The preparation of these financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. While management believes that the amounts included in the Consolidated Financial Statements reflect its best estimates and assumptions, actual results could differ from those estimates. The Company’s principal estimates include: • reserve for losses and loss expenses; • premium estimates for business written on a line slip or proportional basis; • the valuation of goodwill and intangible assets; • reinsurance recoverable balances including the provision for uncollectible amounts; and • investment valuation of financial assets. The term “ASC” used in these notes refers to Accounting Standard Codification issued by the United States Financial Accounting Standards Board (the “FASB”).

Significant accounting policies

Significant accounting policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Significant accounting policies	Significant accounting policies The following is a summary of significant accounting policies adopted by the Company. (a) Premiums Insurance premiums written are recorded in accordance with the terms of underlying policies. Reinsurance premiums written are recorded at the inception of the policy and are estimated based on information received from brokers, ceding companies and reinsureds, and any subsequent differences arising on such estimates will be recorded in the periods in which they are determined. Premiums written are earned on a pro-rated basis over the term of the policy. For contracts and policies written on a losses occurring basis, the risk period is generally the same as the contract or policy terms. For contracts written on a risks attaching basis, the risk period is based on the terms of the underlying contracts and policies and is generally assumed to be 24 months . The portion of the premiums written applicable to the unexpired terms of the underlying contracts and policies in force is recorded as unearned premiums. Reinstatement premiums are recorded at the time a loss event occurs and coverage limits for the remaining life of the contract are reinstated under predefined contract terms. The accrual of reinstatement premiums is based on our estimate of losses and loss expenses, which reflects management’s judgment, as described in Note 3 (c), “ Reserve for losses and loss expenses ” below. (b) Policy acquisition costs Policy acquisition costs are costs that vary with, and are directly related to, the successful production of new and renewal business, and consist principally of commissions and brokerage expenses. Acquisition costs are shown net of commissions earned on reinsurance ceded. These costs are deferred and amortized over the periods in which the related premiums are earned. Deferred acquisition costs are limited to their estimated realizable value based on the related unearned premiums and anticipated claims expenses. The realizable value of the Company’s deferred acquisition costs is determined without consideration of investment income. Policy acquisition costs also include profit commissions. Profit commissions are recognized on a basis consistent with our estimate of losses and loss expenses. (c) Reserve for losses and loss expenses The reserve for losses and loss expenses includes reserves for unpaid reported losses (“case reserves”) and for losses incurred but not reported (“IBNR”). Case reserves are established by management based on reports from brokers, ceding companies and insureds and represents the estimated ultimate cost of events or conditions that have been reported to, or specifically identified by, the Company. IBNR reserves are established by management based on actuarially determined estimates of ultimate losses and loss expenses. Inherent in the estimate of ultimate losses and loss expenses are expected trends in claim severity and frequency and other factors which may vary significantly as claims are settled. Accordingly, ultimate losses and loss expenses may differ materially from the amounts recorded in the Consolidated Financial Statements. These estimates are reviewed regularly and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments, if any, will be recorded in earnings in the period in which they become known. Prior period development arises from changes to these estimates recognized in the current year that relate to reserves for losses and loss expenses established in previous calendar years. (d) Reinsurance In the normal course of business, the Company seeks to reduce the potential amount of loss arising from claims events by reinsuring certain levels of risk assumed in various areas of exposure with other insurers or reinsurers. The accounting for reinsurance ceded depends on the method of reinsurance. If the policy is on a “losses occurring” basis, reinsurance premiums ceded are expensed (and any commissions thereon are earned) on a pro-rata basis over the period the reinsurance coverage is provided. If the policy is a “risks attaching” policy, reinsurance premiums ceded are expensed (and any commissions thereon are earned) in line with the earning of the gross premiums to which the risk attaching policy relates. Prepaid reinsurance premiums represent the portion of premiums ceded applicable to the unexpired term of policies in force. Mandatory reinstatement premiums ceded are recorded at the time the loss event occurs. Reinsurance recoverables are based on contracts in force at the time of the underlying loss event. The method for determining the reinsurance recoverable on unpaid losses and loss expenses involves the actuarial estimates of unpaid losses and loss expenses as well as a determination of the Company’s ability to cede unpaid losses and loss expenses under its reinsurance treaties. The use of different assumptions could have a material effect on the provision for uncollectible reinsurance. To the extent the creditworthiness of the Company’s reinsurers was to deteriorate due to adverse events affecting the reinsurance industry, such as a large number of major catastrophes, actual uncollectible amounts could be significantly greater than the Company’s provision. Amounts recoverable from reinsurers are estimated in a manner consistent with the underlying liabilities. (e) Investments The Company classifies its fixed maturity and short-term investments as trading and accounts for its other investments in accordance with ASC Topic 825 “Financial Instruments.” As such, all investments are carried at fair value with interest and dividend income and realized and unrealized gains and losses included in net income for the year. All investment transactions are recorded on a first-in-first-out basis and realized gains and losses on the sale of investments are determined on the basis of amortized cost (or cost). Interest on fixed maturity securities is recorded in net investment income when earned and includes amortization of premium or accretion of discount. For mortgage-backed securities, and any other holdings for which there is a prepayment risk, prepayment assumptions are evaluated and revised as necessary. Any adjustments required due to the resultant change in effective yields and maturities are recognized retrospectively. Prepayment fees or call premiums that are only payable to the Company when a security is called prior to its maturity, are earned when received and reflected in net investment income. Short-term investments primarily comprise of investments with a remaining maturity of less than one year at time of purchase and money market funds held at the Company’s investment managers. Certain short-term investments relate to funds held in trust in support of collateralized reinsurance transactions. Restricted cash primarily relates to funds held in trust for support of collateralized reinsurance transactions. The fair value of other investments is generally recorded on the basis of the net asset valuation criteria established by the managers of the investments, normally based upon the governing documents of such investments. In addition, due to a lag in reporting, some of the fund managers, fund administrators, or both, are unable to provide final fund valuations as of the Company’s reporting date. In these circumstances, the Company estimates the fair value of these funds by starting with the prior month’s or prior quarter’s fund valuation, adjusting these valuations for capital calls, redemptions or distributions and the impact of changes in foreign currency exchange rates, and then estimating the return for the current period. In circumstances in which the Company estimates the return for the current period, it uses all credible information available. This includes utilizing preliminary estimates reported by its fund managers, obtaining the valuation of underlying portfolio investments where such underlying investments are publicly traded and therefore have a readily observable price, using information that is available to the Company with respect to the underlying investments, reviewing various indices for similar investments or asset classes, as well as estimating returns based on the results of similar types of investments for which the Company has reported results, or other valuation methods, as necessary. Actual final fund valuations may differ, perhaps materially so, from the Company’s estimates and these differences are recorded in the period they become known as a change in estimate. Investments in which the Company has significant influence over the operating and financial policies of the investee are accounted for under the equity method of accounting. Under this method, the Company records its proportionate share of income or loss from such investments in its results for the period. (f) Fair value of financial instruments Fair value is defined as the price received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date reflecting the highest and best use valuation concepts. ASC Topic 820 “ Fair Value Measurement and Disclosure ” provides a framework for measuring fair value by creating a hierarchy of fair value measurements that distinguishes market data between observable independent market inputs and unobservable market assumptions by the reporting entity. The guidance further expands disclosures about such fair value measurements. The guidance applies broadly to most existing accounting pronouncements that require or permit fair value measurements (including both financial and non-financial assets and liabilities) but does not require any new fair value measurements. The Company has adopted all authoritative guidance in effect as of the balance sheet date regarding certain market conditions that allow for fair value measurements that incorporate unobservable inputs where active market transaction based measurements are unavailable. (g) Derivative instruments Fair Value Hedges The Company uses derivative instruments in the form of foreign currency forward exchange contracts to manage foreign currency risk. A foreign currency forward exchange contract involves an obligation to purchase or sell a specified amount of a specified currency at a future date at a price set at the time of the contract. Foreign currency forward exchange contracts will not eliminate fluctuations in the value of our assets and liabilities denominated in foreign currencies but rather allow the Company to establish a rate of exchange for a future point in time. The foreign currency forward exchange contracts are recorded as derivatives at fair value as either assets or liabilities, depending on their rights or obligations, with changes in fair value recorded as a net foreign exchange gain or loss in the Company’s Statements of Income and Comprehensive Income. To qualify for hedge accounting treatment, the derivative must be highly effective in mitigating the designated changes in fair value of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting the changes in fair value of the hedged items. The Company assesses the effectiveness of its designated hedges on an individual currency basis. If the ratio obtained with this method is within the range of 80% to 125% , the Company considers the hedge effective. The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the fair value of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. To the extent that the Company discontinues hedge accounting, because, based on management’s assessment, the derivative no longer qualifies as an effective hedge, the derivative will continue to be carried in the Consolidated Balance Sheets at its fair value, with changes in its fair value recognized in current period net income through foreign exchange gains (losses). Cash Flow Hedges The Company uses derivative instruments in the form of interest rate swaps to manage the interest rate exposure associated with certain assets and liabilities. These derivatives are recorded at fair value. Changes in the fair value of a derivative that is designated and qualifies as a cash flow hedge are recorded in accumulated other comprehensive income (“AOCI”) and are reclassified into earnings when the variability of the cash flow of the hedged item impacts earnings. Gains and losses on derivative contracts that are reclassified from AOCI to current period earnings are included in the line item in the Consolidated Statements of Income and Comprehensive Income in which the cash flows of the hedged item are recorded. Any hedge ineffectiveness is recorded immediately in current period earnings. To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in cash flow of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting the changes in cash flows of the hedged items. The Company assesses the effectiveness of its designated hedges on an individual contract basis. The Company currently applies the long haul method when assessing the hedge’s effectiveness. The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the cash flows of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. When hedge accounting is discontinued because the Company becomes aware that it is not probable that the forecasted transaction will occur, the derivative continues to be carried on the balance sheet at its fair value, and gains and losses that were included as part of AOCI are reclassified and recognized immediately in earnings. (h) Cash and cash equivalents The Company considers time deposits and money market funds with an original maturity of one month or less as equivalent to cash. (i) Foreign exchange The U.S. dollar is the functional currency of the Company and the majority of its subsidiaries. For these companies, monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rates in effect at the balance sheet date and revenues and expenses denominated in foreign currencies are translated at the prevailing exchange rate on the transaction date with the resulting foreign exchange gains and losses included in earnings. Non-monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rate in effect at the time of the underlying transaction. Assets and liabilities of subsidiaries whose functional currency is not the U.S. dollar are translated at prevailing year end exchange rates. Revenue and expenses of such foreign operations are translated at average exchange rates during the year. The net effect of translation differences between functional and reporting currencies in foreign operations, net of applicable deferred income taxes, is included in AOCI. (j) Stock plans The Company accounts for its stock plans in accordance with the ASC Topic 718 “Compensation - Stock Compensation.” Accordingly, the Company recognizes the compensation expense for stock option grants, restricted share grants and performance share awards based on the fair value of the award on the date of grant over the requisite service period. (k) Warrants The Company has accounted for certain warrant contracts issued to our sponsoring investors in conjunction with the capitalization of the Company, and which may be settled by the Company using either the physical settlement or net-share settlement methods, in accordance with ASC Topic 815 “Derivatives and Hedging, Contracts in Entity’s Own Equity. ” Accordingly, the fair value of these warrants has been recorded in equity as an addition to additional paid-in capital. (l) Earnings per share Basic earnings per common share is calculated in accordance with ASC Topic 260 “ Earnings per Share ” by dividing net income available to common shareholders by the weighted average number of common shares outstanding. Earnings per diluted common share are based on the weighted average number of common shares and share equivalents excluding any anti-dilutive effects of warrants, options and other awards under stock plans. (m) Income taxes and uncertain tax provisions Deferred tax assets and liabilities are recorded in accordance with ASC Topic 740 “ Income Taxes .” Consistent with ASC 740, the Company records deferred income taxes which reflect operating losses and tax credits carried forward and the tax effect of the temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and their respective tax bases. The Company and its Bermuda domiciled subsidiaries are not subject to any income, withholding or capital gains taxes under current Bermuda law. The Company has operating subsidiaries in various other jurisdictions around the world, including but not limited to the U.K., U.S., Switzerland, Luxembourg and Canada that are subject to relevant taxes in those jurisdictions. The Company recognizes the tax benefits of uncertain tax positions only where the position is more likely than not to be sustained upon examination by tax authorities based upon the technical merits of the position. Based on the more-likely-than-not recognition threshold, we must presume that the tax position will be subject to examination by a taxing authority with full knowledge of all relevant information. If the recognition threshold is met, then the tax position is measured at the largest amount of benefit that is more than 50% likely of being realized upon ultimate settlement. The Company classifies all interest and penalties related to uncertain tax positions in income tax expenses. (n) Business combinations, goodwill and other intangible assets The Company accounts for business combinations in accordance with ASC Topic 805 “Business Combinations” and goodwill and other intangible assets that arise from business combinations in accordance with ASC Topic 350 “Intangibles – Goodwill and Other .” A purchase price paid that is in excess of the fair value of the net assets acquired (“goodwill”) arising from a business combination is recorded as an asset, and is not amortized. Where the fair value of the net assets acquired exceeds the consideration paid (“negative goodwill”), the acquirer will record a gain as a result of the bargain purchase, to be recognized through the Consolidated Statements of Income and Comprehensive Income at the close of the transaction. Other intangible assets with a finite life are amortized over the estimated useful life of the asset, whereas other intangible assets with an indefinite useful life are not amortized. Goodwill and other intangible assets are assessed for impairment on an annual basis or more frequently if events or changes in circumstances indicate that it is more likely than not that an impairment exists. Such events or circumstances may include an economic downturn in a geographic market or change in the assessment of future operations. In performing this assessment, the Company may first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the quantitative goodwill impairment test. Similarly, the Company may first assess qualitative factors to determine whether it is more likely than not that an other intangible asset is impaired as a basis for determining whether it is necessary to perform the quantitative impairment test. The factors assessed in making this determination included the overall insurance industry outlook, business strategy, premium rates, earnings sustainability, market capitalization and the regulatory and political environment. If goodwill or other intangible assets are impaired, they are written down to their fair value with a corresponding expense reflected in the Consolidated Statements of Income and Comprehensive Income. (n) Variable interest entities The Company determines whether it has relationships with entities defined as VIEs in accordance with ASC Topic 810 “ Consolidation. ” A VIE is consolidated by the variable interest holder that is determined to be the primary beneficiary. An entity in which the Company holds a variable interest is a VIE if any of the following conditions exist: (a) the total equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support, (b) as a group, the holders of equity investment at risk lack either the direct or indirect ability through voting rights or similar rights to make decisions about an entity’s activities that most significantly impact the entity’s economic performance or the obligation to absorb the expected losses or right to receive the expected residual returns, or (c) the voting rights of some investors are disproportionate to their obligation to absorb the expected losses of the entity, their rights to receive the expected residual returns of the entity, or both and substantially all of the entity’s activities either involve or are conducted on behalf of an investor with disproportionately few voting rights. The primary beneficiary is defined as the variable interest holder that is determined to have the controlling financial interest as a result of having both (a) the power to direct the activities of a VIE that most significantly impact the economic performance of the VIE and (b) the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. At inception of the VIE, as well as following an event that requires reassessment, the Company determines whether it is the primary beneficiary based on the facts and circumstances surrounding each entity. (o) Noncontrolling interests The Company accounts for its noncontrolling interests in accordance with ASC Topic 810 “ Consolidation .” Redeemable noncontrolling interests are presented as a mezzanine item, between liabilities and shareholders’ equity, in the Company’s Consolidated Balance Sheet and the non-redeemable noncontrolling interests are presented within shareholders’ equity in the Company’s Consolidated Balance Sheets and Consolidated Statements of Shareholders’ Equity. The net (income) loss attributable to noncontrolling interests is presented separately in the Company’s Consolidated Statements of Income and Comprehensive Income.

Recent accounting pronouncement

Recent accounting pronouncements	12 Months Ended
	Dec. 31, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent accounting pronouncements	Recent accounting pronouncements (a) Accounting Standards Adopted in 2016 In June 2014, the FASB issued Accounting Standard Update (“ASU”) No. 2014-12, “Compensation - Stock Compensation (Topic 718) - Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period.” The amendments in this ASU apply to all reporting entities that grant their employees share-based payments in which the terms of the award provide that a performance target that affects vesting could be achieved after the requisite service period. That is the case when an employee is eligible to retire or otherwise terminate employment before the end of the period in which a performance target (for example, an initial public offering or a profitability target) could be achieved and still be eligible to vest in the award if and when the performance target is achieved. The amendments in this ASU became effective for the Company on January 1, 2016. Adoption of this guidance did not have a material impact on the Company’s Consolidated Financial Statements. In August 2014, the FASB issued ASU 2014-13, “Consolidation (Topic 810) - Measuring the Financial Assets and the Financial Liabilities of a Consolidated Collateralized Financing Entity.” The fair value of the financial assets of a collateralized financing entity, as determined under GAAP, may differ from the fair value of its financial liabilities even when the financial liabilities have recourse only to the financial assets. The amendments in this ASU provide an alternative to Topic 820 for measuring the financial assets and the financial liabilities of a consolidated collateralized financing entity to eliminate that difference. The amendments in this ASU became effective for the Company on January 1, 2016. Adoption of this guidance did not have a material impact on the Company’s Consolidated Financial Statements. In August 2014, the FASB issued ASU 2014-15, “Presentation of Financial Statements - Going Concern (Subtopic 205-40) - Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.” The amendments in this ASU require management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards. The amendments in this ASU became effective for the Company on January 1, 2016. Adoption of this guidance did not have a material impact on the Company’s Consolidated Financial Statements. In May 2015, the FASB issued ASU 2015-09, “Financial Services - Insurance (Topic 944) - Disclosures about Short-Duration Contracts.” The amendments in this ASU enhance annual disclosures relating to reserves for losses and loss expenses by requiring the following: (1) net incurred and paid claims development information by accident year; (2) a reconciliation of incurred and paid claims development information to the aggregate carrying amount of the reserve for losses and loss expenses; (3) for each accident year presented, total IBNR plus expected development on case reserves included in the reserve for losses and loss expenses, accompanied by a description of reserving methodologies and any changes thereto; (4) for each accident year presented, quantitative information about claim frequency (unless impracticable) accompanied by a qualitative description of methodologies used for determining claim frequency information and any changes thereto; and (5) the average annual percentage payout of incurred claims by age for the same number of accident years presented. The amendments in this ASU became effective for the Company on January 1, 2016 and the required annual disclosures have been included in Note 14, “ Reserves for Losses and Loss Expenses.” In September 2015, the FASB issued ASU 2015-16, “Business Combinations (Topic 805) - Simplifying the Accounting for Measurement-Period Adjustments.” The amendments in this ASU simplify the accounting for adjustments made to provisional amounts recognized in a business combination by eliminating the requirement to retrospectively account for those adjustments. The amendments in this ASU became effective for the Company on January 1, 2016. Adoption of this guidance did not have a material impact on the Company’s Consolidated Financial Statements. (b) Recently Issued Accounting Standards Not Yet Adopted In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).” The guidance in this ASU affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets, unless those contracts are within the scope of other standards (for example, insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In March and April 2016, the FASB issued ASU 2016-08, “Revenue from Contracts with Customers (Topic 606) - Principal versus Agent Considerations (Reporting Revenue Gross versus Net)” and ASU 2016-10, “Revenue from Contracts with Customers (Topic 606) - Identifying Performance Obligations and Licensing.” The amendments in these ASUs clarify the implementation guidance within ASU 2014-09 on principal versus agent considerations and the aspects of identifying performance obligations, respectively, while retaining the related principals in those areas. In May 2016, the FASB issued ASU 2016-12, “Revenue from Contracts with Customers (Topic 606) - Narrow-Scope Improvements and Practical Expedients.” The amendments in this ASU do not change the core principle of the guidance in Topic 606. Rather, the amendments provide clarifying guidance in a few narrow areas and add practical expedients to reduce the potential for diversity in practice as well as the cost and complexity of applying the guidance. In December 2016, the FASB issued ASU 2016-20, “Technical Corrections and Improvements to Topic 606 - Revenue from Contracts with Customers.” The amendments in this ASU affect narrow aspects of the guidance issued in ASU 2014-09. The original effective date for the amendments in ASU 2014-09 was for annual reporting periods beginning after December 15, 2016; however, in August 2015, the FASB delayed the effective date by one year through the issuance of ASU 2015-14, “Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date.” As such, the new effective date is for interim and annual reporting periods beginning after December 15, 2017. Entities may adopt the standard as of the original effective date; however, earlier adoption is not permitted. The Company has evaluated this guidance and determined it will likely impact the timing of when performance fees are recognized by AlphaCat Managers Ltd. (“AlphaCat Managers”). Currently, performance fees are recognized by AlphaCat Managers monthly, on a seasonal basis, in line with the underlying insurance contracts of the ILS it manages. However, upon adoption, performance fees will only be recognized when it’s probable that a significant reversal of the amount of cumulative revenue recognized will not occur. While performance fees are variable and dependent on the results of the AlphaCat sidecars and higher risk ILS funds, the impact on the results of the Company would not be material. The Company plans to adopt this guidance on January 1, 2018. In January 2016, the FASB issued ASU 2016-01, “Financial Instruments - Overall (Subtopic 825-10) - Recognition and measurement of financial assets and financial liabilities.” The amendments in this ASU address certain aspects of recognition, measurement and disclosure of financial instruments and are effective for interim and annual reporting periods beginning after December 15, 2017. Early adoption is not permitted. The Company has evaluated the impact of this guidance and it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2018. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842).” The amendments in this ASU increase the transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and requiring the disclosure of key information about leasing arrangements. The amendments in this ASU are effective for interim and annual reporting periods beginning after December 15, 2018. Early adoption is permitted. Upon adoption, the Company expects to report higher assets and liabilities as a result of recognizing lease assets and liabilities on the Consolidated Balance Sheet. The Company does not expect the new guidance to have a significant impact on the Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2019. In March 2016, the FASB issued ASU 2016-07, “Investments-Equity Method and Joint Ventures (Topic 323) - Simplifying the Transition to the Equity Method of Accounting.” The amendments in this ASU eliminate the requirement to retroactively adopt the equity method of accounting when an investment becomes qualified for the equity method of accounting as a result of an increase in the level of ownership interest or degree of influence. The amendments in this ASU are effective for interim and annual reporting periods beginning after December 15, 2016. Early adoption is permitted. The Company has evaluated the impact of this guidance and it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2017. In March 2016, the FASB issued ASU 2016-09, “Compensation-Stock Compensation (Topic 718) - Improvements to Employee Share-Based Payment Accounting.” The amendments in this ASU simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. The amendments in this ASU are effective for interim and annual reporting periods beginning after December 15, 2016. Early adoption is permitted. The Company has evaluated the impact of this guidance and it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2017. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326).” The new guidance introduces an approach based on expected losses to estimate credit losses on certain types of financial instruments. It also modifies the impairment model for available-for-sale debt securities and provides for a simplified accounting model for purchased financial assets with credit deterioration since their origination. This guidance is effective for annual periods beginning after December 15, 2019, and interim periods within those fiscal years. Early adoption is permitted for annual periods beginning after December 15, 2018, and interim periods within those fiscal years. This ASU also impacts the assessment of the recoverability of the Company’s reinsurance balances recoverable. The Company evaluates the financial condition of its reinsurers and monitors concentration of credit risk arising from its exposure to individual reinsurers. The reinsurance program is generally placed with reinsurers whose rating, at the time of placement, was A- or better as rated by Standard & Poor’s or the equivalent with other rating agencies. As at December 31, 2016, 99.1% of the Company’s total reinsurance balances recoverable were either fully collateralized or recoverable from reinsurers rated A- or better. As a result, the Company does not expect the new guidance to have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2020. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230) - Classification of Certain Cash Receipts and Cash Payments.” This ASU is directed at reducing diversity in practice and addresses eight specific issues in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The ASU is effective for fiscal periods beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. Any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. An entity that elects early adoption must adopt all of the amendments in the same period. The amendments in this ASU should be applied using a retrospective transition method to each period presented. If it is impracticable to apply the amendments retrospectively for some of the issues, the amendments for those issues would be applied prospectively as of the earliest date practicable. The Company has evaluated the impact of this guidance and it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2018. In October 2016, the FASB issued ASU 2016-16, “Income Taxes (Topic 740) - Intra-Entity Transfers of Assets Other Than Inventory.” This ASU aims to improve the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. Current U.S. GAAP prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. The ASU states that an entity should recognize the income tax consequences of an intra-entity transfer of an asset, other than inventory, when the transfer occurs. The ASU does not include new disclosure requirements; however, existing disclosure requirements might be applicable when accounting for the current and deferred income taxes for an intra-entity transfer of an asset other than inventory. The ASU is effective for fiscal periods beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted for all entities as of the beginning of an annual reporting period for which financial statements (interim or annual) have not been issued or made available for issuance. That is, earlier adoption should be in the first interim period if an entity issues interim financial statements. The Company has evaluated the impact of this guidance and determined that it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2018. In October 2016, the FASB issued ASU 2016-17, “Consolidation (Topic 810) - Interests Held Through Related Parties That Are Under Common Control.” The amendments in this ASU do not change the characteristics of a primary beneficiary in current U.S. GAAP. Rather, the ASU requires that a reporting entity, in determining whether it satisfies the second characteristic of a primary beneficiary, include all of its direct variable interests in a VIE and, on a proportionate basis, its indirect variable interests in a VIE held through related parties, including related parties that are under common control with the reporting entity. The ASU is effective for public business entities for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. Entities that already have adopted ASU 2015-02 are required to apply the amendments in this ASU retrospectively to all relevant prior periods beginning with the fiscal year in which ASU 2015-02 initially were applied. The Company has evaluated the impact of this guidance and it will not have a material impact on the Company’s Consolidated Financial Statements.The Company plans to adopt this guidance on January 1, 2017. In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230) - Restricted Cash.” This ASU is directed at reducing diversity that exists in the classification and presentation of changes in restricted cash on the statement of cash flows. The ASU is effective for fiscal periods beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. Any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. The amendments in this ASU should be applied using a retrospective transition method to each period presented. The Company has evaluated the impact of this guidance and determined that it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this guidance on January 1, 2018. In January 2017, the FASB issued ASU 2017-01, “Business Combinations (Topic 805) - Clarifying the Definition of a Business.” The amendments in this ASU clarify the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. This ASU is effective for fiscal periods beginning after December 15, 2017, and interim periods within those fiscal years. The amendments in this ASU should be applied prospectively on or after the effective date. No disclosures are required at transition and early application is allowed in certain situations. The Company has evaluated the impact of this guidance and determined that it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this ASU on January 1, 2018. In January 2017, the FASB issued ASU 2017-04, “Intangibles - Goodwill and Other (Topic 350).” The amendments in this ASU simplify the subsequent measurement of goodwill by eliminating Step 2 from the goodwill impairment test. Under this ASU, an entity would perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when measuring the goodwill impairment loss, if applicable. This ASU is effective for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. The Company completed its qualitative assessments for impairment of both goodwill and other intangible assets and concluded that there had been no impairment as at December 31, 2016. The Company has evaluated the impact of this guidance and determined that it will not have a material impact on the Company’s Consolidated Financial Statements. The Company plans to adopt this ASU on January 1, 2020.

Business combination

Business combination	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Business combination	Business combination Western World Insurance Group, Inc. On October 2, 2014, Validus Specialty, Inc., a wholly owned subsidiary of the Company, acquired all of the issued and outstanding capital stock of Western World for an aggregate purchase price of $692,305 in cash. The Western World acquisition was undertaken to enhance the Company’s access to the specialty U.S. commercial insurance market. Additional factors that added to the value of Western World included its State Licenses, Brand Name, Distribution Network and Technology. These factors resulted in a market value greater than the value of net tangible and intangible assets which resulted in the recognition of goodwill. This goodwill is reflective of the strategic benefits that a U.S. based insurer can provide to the Company. For reporting purposes, the results of Western World’s operations have been included in the Consolidated Financial Statements as a separate segment from the acquisition date. The estimates of fair values for tangible and intangible assets acquired and liabilities assumed were determined by management based on various market and income analyses. Significant judgment was required to arrive at these estimates of fair value and changes to assumptions used could have led to materially different results. The fair value of net assets acquired, including pro forma U.S. GAAP adjustments, are summarized as follows: Total purchase price $ 692,305 Assets acquired Cash and cash equivalents $ 48,760 Investments 1,126,185 Receivables 37,848 Other assets 19,418 Tangible assets acquired 1,232,211 Intangible asset - State licenses $ 12,325 Intangible asset - Brand name 5,756 Intangible asset - Distribution network 4,651 Intangible asset - Technology 2,323 Intangible assets acquired $ 25,055 Liabilities acquired Net loss reserves and paid losses recoverable $ 523,315 Unearned premiums, net of expenses 135,686 Other liabilities 81,464 Liabilities acquired 740,465 Excess purchase price (goodwill) as at December 31, 2014 $ 175,504 Measurement period adjustments (a) 861 Excess purchase price (goodwill) as at December 31, 2015 $ 176,365 (a) During the year ended December 31, 2015, measurement period adjustments of $861 were made to certain other assets, net of taxes. For details on the intangible assets acquired, refer to Note 6 , “ Goodwill and other intangible assets. ” The Company also incurred transaction expenses related to the Western World acquisition. Transaction expenses included legal, financial advisory and audit related services. Supplemental Pro Forma Information Operating results of Western World have been included in the Consolidated Financial Statements from the October 2, 2014 acquisition date. The following selected unaudited pro forma financial information has been provided to present a summary of the combined results of the Company and Western World, assuming the transaction had been effected on January 1, 2014. The unaudited pro forma data is for informational purposes only and does not necessarily represent results that would have occurred if the transaction had taken place on the basis assumed above. Year Ended December 31, 2014 (Dollars in thousands) Unaudited Net premiums earned $ 2,216,349 Net operating income $ 481,179 Net income $ 448,071 The following selected audited information has been provided to present a summary of the results of Western World that have been included in the Consolidated Financial Statements for the year ended December 31, 2014. From Acquisition Date to (Dollars in thousands) December 31, 2014 Net premiums written $ 58,807 Total revenue 78,325 Total expenses (66,882 ) Net income $ 11,443

Goodwill and other intangible a

Goodwill and other intangible assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and other intangible assets	Goodwill and other intangible assets The following table presents a reconciliation of the beginning and ending goodwill and other intangible assets for the years ended December 31, 2016 and 2015 : Year Ended December 31, 2016 Goodwill Other Intangible Assets Talbot Western World Total With a Finite Life With an Indefinite Life Total Balance, beginning of year $ 20,393 $ 176,365 $ 196,758 $ 17,090 $ 104,168 $ 121,258 Amortization — — — (5,666 ) — (5,666 ) Balance, end of year $ 20,393 $ 176,365 $ 196,758 $ 11,424 $ 104,168 $ 115,592 Year Ended December 31, 2015 Goodwill Other Intangible Assets Talbot Western World Total With a Finite Life With an Indefinite Life Total Balance, beginning of year $ 20,393 $ 175,504 $ 195,897 $ 22,756 $ 104,168 $ 126,924 Amortization — — — (5,666 ) — (5,666 ) Measurement period adjustments — 861 861 — — — Balance, end of year $ 20,393 $ 176,365 $ 196,758 $ 17,090 $ 104,168 $ 121,258 Goodwill relates to the Company’s 2007 acquisition of Talbot and 2014 acquisition of Western World. As at December 31, 2016 and 2015 , the total amount of carried goodwill was $196,758 . During the year ended December 31, 2015 , measurement period adjustments of $861 were made to certain other assets, net of taxes, for Western World. Other intangible assets with a finite life includes the distribution network, technology, trade name and customer relationships related to the Company’s acquisitions of Talbot and Western World. These assets are amortized on a straight-line basis over a period ranging from 5 to 10 years. Amortization expense associated with these assets for the years ended December 31, 2016 , 2015 and 2014 was $5,666 , $5,666 and $4,538 , respectively. Other intangible assets with an indefinite life consist of U.S. state licenses that provide a legal right to transact business indefinitely which were acquired with the Company’s acquisition of Western World, along with Lloyd’s Syndicate capacity related to the Company’s acquisition of Talbot. The Company completed its qualitative assessments for impairment of both goodwill and other intangible assets and concluded that there had been no impairment as at December 31, 2016 and 2015 . The gross carrying value, accumulated amortization and net carrying value of other intangible assets by type as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Other intangible assets with a finite life Trade name and customer relationships $ 18,189 $ (13,406 ) $ 4,783 $ 18,189 $ (12,187 ) $ 6,002 Distribution network 39,831 (34,468 ) 5,363 39,831 (30,485 ) 9,346 Technology 2,323 (1,045 ) 1,278 2,323 (581 ) 1,742 Total $ 60,343 $ (48,919 ) $ 11,424 $ 60,343 $ (43,253 ) $ 17,090 Other intangible assets with an indefinite life Syndicate capacity $ 91,843 n/a $ 91,843 $ 91,843 n/a $ 91,843 State licenses 12,325 n/a 12,325 12,325 n/a 12,325 Total $ 104,168 $ 104,168 $ 104,168 $ 104,168 The estimated remaining amortization expense for the Company’s other intangible assets with a finite life is as follows: Total Remaining Amortization Expense 2017 $ 3,585 2018 1,505 2019 1,389 2020 1,041 2021 1,041 2022 and thereafter 2,863 $ 11,424

Investments

Investments	12 Months Ended
	Dec. 31, 2016
Investments [Abstract]
Investments	Investments Managed investments represent assets governed by the Company’s investment policy statement (“IPS”) whereas, non-managed investments represent assets held in support of consolidated AlphaCat VIEs which are not governed by the Company’s IPS. Refer to Note 9 , “Variable interest entities,” for further details. The amortized cost (or cost) and fair value of the Company’s investments as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Amortized Cost or Cost Fair Value Amortized Fair Value Managed investments U.S. government and government agency $ 809,392 $ 804,126 $ 940,428 $ 937,202 Non-U.S. government and government agency 245,651 240,791 241,549 237,968 U.S. states, municipalities and political subdivisions 271,742 271,830 299,929 301,289 Agency residential mortgage-backed securities 684,490 679,595 606,676 610,582 Non-agency residential mortgage-backed securities 15,858 15,477 27,025 26,920 U.S. corporate 1,540,036 1,534,508 1,503,614 1,489,951 Non-U.S. corporate 418,520 410,227 453,178 446,570 Bank loans 579,121 570,399 592,981 576,211 Asset-backed securities 528,563 526,814 440,363 437,124 Commercial mortgage-backed securities 333,740 330,932 263,310 260,135 Total fixed maturities 5,427,113 5,384,699 5,369,053 5,323,952 Short-term investments 228,574 228,386 237,349 237,369 Other investments Fund of hedge funds 1,457 955 1,457 1,417 Hedge funds 11,292 17,381 14,018 20,980 Private equity investments 72,814 89,809 53,489 63,771 Fixed income investment funds 241,536 242,093 188,121 188,721 Overseas deposits 50,106 50,106 54,484 54,484 Mutual funds 2,925 5,368 4,394 7,483 Total other investments 380,130 405,712 315,963 336,856 Investments in investment affiliates (a) 84,840 100,431 69,794 87,673 Total managed investments $ 6,120,657 $ 6,119,228 $ 5,992,159 $ 5,985,850 Non-managed investments Catastrophe bonds $ 157,486 $ 158,331 $ 187,847 $ 186,379 Short-term investments 2,567,784 2,567,784 1,704,266 1,704,266 Total non-managed investments 2,725,270 2,726,115 1,892,113 1,890,645 Total investments $ 8,845,927 $ 8,845,343 $ 7,884,272 $ 7,876,495 (a) The Company’s investments in investment affiliates have been treated as equity method investments with the corresponding gains and losses recorded in income as “Income (loss) from investment affiliates.” (a) Fixed maturity investments The following table sets forth certain information regarding the investment ratings of the Company’s fixed maturity investments as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Fair Value % of Total Fair Value % of Total Managed fixed maturities AAA $ 2,405,597 43.4 % $ 2,367,642 43.0 % AA 538,289 9.7 % 569,386 10.3 % A 1,081,949 19.5 % 1,031,326 18.7 % BBB 740,861 13.4 % 691,538 12.6 % Total investment grade managed fixed maturities 4,766,696 86.0 % 4,659,892 84.6 % BB 213,568 3.9 % 235,724 4.3 % B 177,737 3.2 % 179,069 3.2 % CCC 13,371 0.2 % 5,706 0.1 % CC — 0.0 % 1,015 0.0 % NR 213,327 3.8 % 242,546 4.4 % Total non-investment grade managed fixed maturities 618,003 11.1 % 664,060 12.0 % Total managed fixed maturities $ 5,384,699 97.1 % $ 5,323,952 96.6 % Non-managed fixed maturities BBB $ — 0.0 % $ 1,911 0.0 % Total investment grade non-managed catastrophe bonds — 0.0 % 1,911 0.0 % BB 29,731 0.6 % 70,962 1.3 % B 4,524 0.1 % 30,698 0.6 % NR 124,076 2.2 % 82,808 1.5 % Total non-investment grade non-managed catastrophe bonds 158,331 2.9 % 184,468 3.4 % Total non-managed fixed maturities 158,331 2.9 % 186,379 3.4 % Total fixed maturities $ 5,543,030 100.0 % $ 5,510,331 100.0 % The amortized cost and estimated fair value amounts for the Company’s fixed maturity investments held at December 31, 2016 and 2015 are shown below by contractual maturity. Actual maturity may differ from contractual maturity because certain borrowers may have the right to call or prepay certain obligations with or without call or prepayment penalties. December 31, 2016 December 31, 2015 Amortized Cost Fair Value Amortized Cost Fair Value Managed fixed maturities Due in one year or less $ 350,733 $ 346,161 $ 367,132 $ 366,019 Due after one year through five years 2,954,856 2,933,146 2,965,920 2,936,053 Due after five years through ten years 430,365 426,647 548,183 539,083 Due after ten years 128,508 125,927 150,444 148,036 3,864,462 3,831,881 4,031,679 3,989,191 Asset-backed and mortgage-backed securities 1,562,651 1,552,818 1,337,374 1,334,761 Total managed fixed maturities $ 5,427,113 $ 5,384,699 $ 5,369,053 $ 5,323,952 Non-managed catastrophe bonds Due in one year or less $ 43,664 $ 45,418 $ 7,504 $ 7,544 Due after one year through five years 112,572 111,656 165,093 163,575 Due after five years through ten years 1,250 1,257 15,250 15,260 Due after ten years — — — — Total non-managed fixed maturities 157,486 158,331 187,847 186,379 Total fixed maturities $ 5,584,599 $ 5,543,030 $ 5,556,900 $ 5,510,331 (b) Other investments The following tables set forth certain information regarding the Company’s other investments as at December 31, 2016 and 2015 : December 31, 2016 Fair Value Investments with redemption restrictions Investments without redemption restrictions Redemption frequency (a) Redemption notice period (a) Fund of hedge funds $ 955 $ 955 $ — Hedge funds 17,381 17,381 — Private equity investments 89,809 89,809 — Fixed income investment funds 242,093 211,151 30,942 Daily 2 days Overseas deposits 50,106 50,106 — Mutual funds 5,368 — 5,368 Daily Daily Total other investments $ 405,712 $ 369,402 $ 36,310 December 31, 2015 Fair Value Investments with redemption restrictions Investments without redemption restrictions Redemption frequency (a) Redemption notice period (a) Fund of hedge funds $ 1,417 $ 1,417 $ — Hedge funds 20,980 20,980 — Private equity investments 63,771 63,771 — Fixed income investment funds 188,721 167,910 20,811 Daily 2 days Overseas deposits 54,484 54,484 — Mutual funds 7,483 — 7,483 Daily Daily Total other investments $ 336,856 $ 308,562 $ 28,294 (a) The redemption frequency and notice periods only apply to investments without redemption restrictions. Other investments include alternative investments in various funds and pooled investment schemes. These alternative investments employ various investment strategies primarily involving, but not limited to, investments in collateralized obligations, fixed income securities, private equities, distressed debt and equity securities. Certain securities included in other investments are subject to redemption restrictions and are unable to be redeemed from the funds. Distributions from these funds will be received as the underlying investments of the funds are liquidated. Currently, it is not known to the Company when these underlying assets will be sold by their investment managers; however, it is estimated that the majority of the underlying assets of the investments would liquidate over five to ten years from inception of the funds. In addition, one of the fixed income investment funds with a fair value of $184,749 ( December 31, 2015 : $167,910 ), has a lock-up period of three years as at December 31, 2016 and may also impose a redemption gate. A lock-up period refers to the initial amount of time an investor is contractually required to remain invested before having the ability to redeem. Typically, the imposition of a gate delays a portion of the requested redemption, with the remaining portion settled in cash shortly after the redemption date. Furthermore, the underlying investments held in the overseas deposit funds are liquid and will generally trade freely in an open market. However, the Company’s ability to withdraw from the overseas deposit funds is restricted by an annual and quarterly, funding and release process for Lloyd’s market participants. The Company’s maximum exposure to any of these alternative investments is limited to the invested amounts and any remaining capital commitments. Refer to Note 23 , “Commitments and contingencies,” for further details. As at December 31, 2016 , the Company does not have any plans to sell any of the other investments listed above. (c) Investments in investment affiliates Aquiline Financial Services Fund II L.P. On December 20, 2011, the Company entered into an Assignment and Assumption Agreement (the “Agreement”) with Aquiline Capital Partners LLC, a Delaware limited liability company (the “Assignor”) and Aquiline Capital Partners II GP (Offshore) Ltd., a Cayman Islands company limited by shares (the “Aquiline II General Partner”) pursuant to which the Company has assumed 100% of the Assignor’s interest in Aquiline Financial Services Fund II L.P. (the “Aquiline II Partnership”) representing a total capital commitment of $50,000 (the “Aquiline II Commitment”), as a limited partner in the Partnership (the “Transferred Interest”). The Transferred Interest is governed by the terms of an Amended and Restated Exempted Limited Partnership Agreement of the Fund. On October 2, 2014, the Company assumed an additional investment in the Aquiline II Partnership as part of the Western World acquisition representing a total capital commitment of $10,000 . This interest is also governed by the terms of the Aquiline II Limited Partnership Agreement. The Aquiline II Partnership is a VIE and the Company is not the primary beneficiary. Therefore, the Company’s investment in the Aquiline II Partnership has been treated as an equity method investment. The Aquiline II Partnership provides a quarterly capital account statement, with a three month delay in its valuation, which was used as the basis for calculating the Company’s share of partnership income for the period. In accordance with the terms of the Agreement, no limited partner has the right to withdraw from the Aquiline II Partnership or to withdraw any part of its capital account without prior consent from the Aquiline II General Partner. The Company’s maximum exposure to the Aquiline II Partnership is limited to the amount invested and any remaining capital commitment. Refer to Note 23 , “Commitments and contingencies,” for further details. Aquiline Financial Services Fund III L.P. On November 7, 2014, the Company, entered into a Subscription Agreement (the “Subscription Agreement”) with Aquiline Capital Partners III GP (Offshore) Ltd., a Cayman Islands company limited by shares (the “Aquiline III General Partner”) pursuant to which the Company committed and agreed to purchase limited partnership or other comparable limited liability equity interests (the “Limited Partnership Interests”) in Aquiline Financial Services Fund III L.P., a Cayman Islands exempted limited partnership (the “Aquiline III Partnership”), and/or one or more Alternative Investment Vehicles and Intermediate Entities (together with the Aquiline III Partnership, the “Fund” or the “Entities”) with a capital commitment (the “Aquiline III Commitment”) in an amount equal to $100,000 , as a limited partner in the Aquiline III Partnership. The Limited Partnership Interests are governed by the terms of an Amended and Restated Exempted Limited Partnership Agreement. The Aquiline III Partnership is a VIE and the Company is not the primary beneficiary. Therefore, the Company’s investment in the Aquiline III Partnership has been treated as an equity method investment. The Aquiline III Partnership provides a quarterly capital account statement, with a three month delay in its valuation, which was used as the basis for calculating the Company’s share of partnership income for the period. In accordance with the terms of the Agreement, no limited partner has the right to withdraw from the Aquiline III Partnership or to withdraw any part of its capital account without prior consent from the Aquiline III General Partner. The Company’s maximum exposure to the Aquiline III Partnership is limited to the amount invested and any remaining capital commitment. Refer to Note 23 , “Commitments and contingencies,” for further details. The following table presents a reconciliation of the Company’s beginning and ending investments in investment affiliates for the years ended December 31, 2016 and 2015 : Years Ended December 31, 2016 2015 Investment affiliates, beginning of year $ 87,673 $ 63,506 Net capital contributions 14,841 19,886 (Loss) income from investment affiliate (2,083 ) 4,281 Investment affiliates, end of year $ 100,431 $ 87,673 The following table presents the Company’s investments in the partnerships as at December 31, 2016 and 2015: December 31, 2016 Investment at cost Voting ownership % Equity ownership % Carrying value Aquiline II Partnership $ 46,871 — % 8.1 % $ 61,999 Aquiline III Partnership 37,969 — % 9.0 % 38,432 Total $ 84,840 $ 100,431 December 31, 2015 Investment at cost Voting ownership % Equity ownership % Carrying value Aquiline II Partnership $ 55,904 — % 8.1 % $ 73,880 Aquiline III Partnership 13,890 — % 13.7 % 13,793 Total $ 69,794 $ 87,673 (d) Net investment income Net investment income was derived from the following sources: Years Ended December 31, 2016 2015 2014 Managed investments Fixed maturities and short-term investments $ 119,085 $ 113,627 $ 93,044 Other investments 27,860 13,307 5,111 Cash and cash equivalents and restricted cash 2,939 1,911 5,106 Securities lending income 55 16 11 Total gross investment income 149,939 128,861 103,272 Investment expenses (8,221 ) (7,695 ) (7,472 ) Total managed net investment income $ 141,718 $ 121,166 $ 95,800 Non managed investments Fixed maturities and short-term investments $ 6,931 $ 6,528 $ 4,204 Cash and cash equivalents and restricted cash 1,736 130 82 Total non-managed net investment income 8,667 6,658 4,286 Total net investment income $ 150,385 $ 127,824 $ 100,086 Net investment income from other investments includes distributed and undistributed net income from certain fixed income investment funds. (e) Net realized gains and change in net unrealized gains (losses) on investments The following table sets forth an analysis of net realized gains and the change in net unrealized gains (losses) on investments: Years Ended December 31, 2016 2015 2014 Managed fixed maturities, short-term and other investments Gross realized gains $ 22,491 $ 15,678 $ 20,201 Gross realized (losses) (7,811 ) (13,980 ) (8,041 ) Net realized gains on investments 14,680 1,698 12,160 Change in net unrealized gains (losses) on investments 14,106 (32,007 ) (1,030 ) Total net realized and change in net unrealized gains (losses) on managed investments $ 28,786 $ (30,309 ) $ 11,130 Non-managed fixed maturities, short-term and other investments Gross realized gains $ 1,086 $ 611 $ 2,757 Gross realized (losses) (9 ) (11 ) — Net realized gains on investments 1,077 600 2,757 Change in net unrealized gains (losses) on investments 2,765 (388 ) (1,812 ) Total net realized and change in net unrealized gains on non-managed investments 3,842 212 945 Total net realized and change in net unrealized gains (losses) on total investments $ 32,628 $ (30,097 ) $ 12,075 (f) Pledged investments and cash As at December 31, 2016 , the Company had $5,173,966 ( December 31, 2015 : $4,056,788 ) of cash and cash equivalents, restricted cash, short-term investments and fixed maturity investments that were pledged during the normal course of business. Of those, $5,068,092 were held in trust ( December 31, 2015 : $4,007,215 ). Pledged assets are generally for the benefit of the Company’s cedants and policyholders, to support AlphaCat’s fully collateralized reinsurance transactions and to facilitate the accreditation of Validus Reinsurance, Ltd., Validus Reinsurance (Switzerland) Ltd. (“Validus Re Swiss”) and Talbot as an alien insurer/reinsurer by certain regulators. In addition, the Company has pledged cash and investments as collateral under the Company’s credit facilities in the amount of $442,184 (December 31, 2015: $826,535 ). For further details on the credit facilities, refer to Note 20 “ Debt and financing arrangements .” During 2014, Validus Reinsurance, Ltd. established a Multi-Beneficiary Reinsurance Trust (“MBRT”) to collateralize its (re)insurance liabilities associated with and for the benefit of U.S. domiciled cedants who, as a result, will receive automatic credit in their regulatory filings for the reinsurance provided prospectively by the Company. As of December 31, 2016 , Validus Reinsurance, Ltd. was approved as a trusteed reinsurer in 48 states as well as Puerto Rico and the District of Columbia. In addition, Validus Re Swiss established a MBRT in December 2015 and was approved as a trusteed reinsurer in 44 states as well as Puerto Rico and the District of Columbia as at December 31, 2016 . (g) Securities lending The Company participates in a securities lending program whereby certain securities from its portfolio are loaned to third parties for short periods of time through a lending agent. The Company retains all economic interest in the securities it lends and receives a fee from the borrower for the temporary use of the securities. Collateral in the form of cash, government securities and letters of credit is required at a rate of 102% of the market value of the loaned securities and is held by a third party.

Fair value measurements

Fair value measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair value measurements	Fair value measurements (a) Classification within the fair value hierarchy Fair value is defined as the price to sell an asset or transfer a liability in an orderly transaction between market participants. Under U.S. GAAP, a company must determine the appropriate level in the fair value hierarchy for each fair value measurement. The fair value hierarchy prioritizes the inputs, which refer broadly to assumptions market participants would use in pricing an asset or liability, into three levels. It gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The level in the fair value hierarchy within which a fair value measurement in its entirety falls is determined based on the lowest level input that is significant to the fair value measurement in its entirety. The three levels of the fair value hierarchy are described below: Level 1 - Fair values are measured based on unadjusted quoted prices in active markets for identical assets or liabilities that we have the ability to access. Level 2 - Fair values are measured based on quoted prices in active markets for similar assets or liabilities, quoted prices for identical assets or liabilities in inactive markets, or for which significant inputs are observable (e.g., interest rates, yield curves, prepayment speeds, default rates, loss severities, etc.) or can be corroborated by observable market data. Level 3 - Fair values are measured based on inputs that are unobservable and significant to the overall fair value measurement. The unobservable inputs reflect the Company’s own judgments about assumptions where there is little, if any, market activity for that asset or liability that market participants might use. The availability of observable inputs can vary from financial instrument to financial instrument and is affected by a wide variety of factors including, for example, the type of financial instrument, whether the financial instrument is new and not yet established in the marketplace, and other characteristics particular to the instrument. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires significantly more judgment. Accordingly, the degree of judgment exercised by management in determining fair value is greatest for instruments categorized in Level 3. In periods of market dislocation, the observability of prices and inputs may be reduced for many instruments. This may lead the Company to change the selection of our valuation technique (for example, from market to cash flow approach) or to use multiple valuation techniques to estimate the fair value of a financial instrument. These circumstances could cause an instrument to be reclassified between levels within the fair value hierarchy. During 2015, the Company early adopted and implemented ASU 2015-07, “Fair Value Measurement (Topic 820) - Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent).” As such, the investments measured at fair value using the net asset value ( “ NAV ” ) per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. At December 31, 2016 , the Company’s investments were allocated between Levels 1, 2 and 3 as follows: Level 1 Level 2 Level 3 Fair value based on NAV practical expedient Total Managed investments U.S. government and government agency $ — $ 804,126 $ — $ — $ 804,126 Non-U.S. government and government agency — 240,791 — — 240,791 U.S. states, municipalities and political subdivisions — 271,830 — — 271,830 Agency residential mortgage-backed securities — 679,595 — — 679,595 Non-agency residential mortgage-backed securities — 15,477 — — 15,477 U.S. corporate — 1,534,508 — — 1,534,508 Non-U.S. corporate — 410,227 — — 410,227 Bank loans — 323,903 246,496 — 570,399 Asset-backed securities — 502,883 23,931 — 526,814 Commercial mortgage-backed securities — 330,932 — — 330,932 Total fixed maturities — 5,114,272 270,427 — 5,384,699 Short-term investments 209,651 18,735 — — 228,386 Other investments Fund of hedge funds — — — 955 955 Hedge funds — — — 17,381 17,381 Private equity investments — — — 89,809 89,809 Fixed income investment funds — 30,941 12,168 198,984 242,093 Overseas deposits — — — 50,106 50,106 Mutual funds — 5,368 — — 5,368 Total other investments — 36,309 12,168 357,235 405,712 Investments in investment affiliates (a) — — — — 100,431 Total managed investments $ 209,651 $ 5,169,316 $ 282,595 $ 357,235 $ 6,119,228 Non-managed investments Catastrophe bonds $ — $ 109,956 $ 48,375 $ — $ 158,331 Short-term investments 2,567,784 — — — 2,567,784 Total non-managed investments 2,567,784 109,956 48,375 — 2,726,115 Total investments $ 2,777,435 $ 5,279,272 $ 330,970 $ 357,235 $ 8,845,343 (a) In accordance with ASC Topic 825 “Financial Instruments,” the Company’s investments in investment affiliates have not been classified in the fair value hierarchy. At December 31, 2015 , the Company’s investments were allocated between Levels 1, 2 and 3 as follows: Level 1 Level 2 Level 3 Fair value based on NAV practical expedient Total Managed investments U.S. government and government agency $ — $ 937,202 $ — $ — $ 937,202 Non-U.S. government and government agency — 237,968 — — 237,968 U.S. states, municipalities and political subdivisions — 301,289 — — 301,289 Agency residential mortgage-backed securities — 610,582 — — 610,582 Non-agency residential mortgage-backed securities — 26,920 — — 26,920 U.S. corporate — 1,489,951 — — 1,489,951 Non-U.S. corporate — 446,570 — — 446,570 Bank loans — 343,874 232,337 — 576,211 Asset-backed securities — 437,124 — — 437,124 Commercial mortgage-backed securities — 260,135 — — 260,135 Total fixed maturities — 5,091,615 232,337 — 5,323,952 Short-term investments 222,678 14,691 — — 237,369 Other investments Fund of hedge funds — — — 1,417 1,417 Hedge funds — — — 20,980 20,980 Private equity investments — — — 63,771 63,771 Fixed income investment funds — 20,811 — 167,910 188,721 Overseas deposits — — — 54,484 54,484 Mutual funds — 7,483 — — 7,483 Total other investments — 28,294 — 308,562 336,856 Investments in investment affiliates (a) — — — — 87,673 Total managed investments $ 222,678 $ 5,134,600 $ 232,337 $ 308,562 $ 5,985,850 Non-managed investments Catastrophe bonds $ — $ 172,879 $ 13,500 $ — $ 186,379 Short-term investments 1,704,266 — — — 1,704,266 Total non-managed investments 1,704,266 172,879 13,500 — 1,890,645 Total investments $ 1,926,944 $ 5,307,479 $ 245,837 $ 308,562 $ 7,876,495 (a) In accordance with ASC Topic 825 “Financial Instruments,” the Company’s investments in investment affiliates have not been classified in the fair value hierarchy. At December 31, 2016 , managed Level 3 investments totaled $282,595 (December 31, 2015 : $232,337 ), representing 4.6% (December 31, 2015 : 3.9% ) of total managed investments. (b) Valuation techniques There have been no material changes in the Company’s valuation techniques during the period, or periods, represented by these Consolidated Financial Statements. The following methods and assumptions were used in estimating the fair value of each class of financial instrument recorded in the Consolidated Balance Sheets. Fixed maturity investments In general, valuation of the Company’s fixed maturity investment portfolio is provided by pricing services, such as index providers and pricing vendors, as well as broker quotations. The pricing vendors provide valuations for a high volume of liquid securities that are actively traded. For securities that do not trade on an exchange, the pricing services generally utilize market data and other observable inputs in matrix pricing models to determine month end prices. Prices are generally verified using third party data. Securities which are priced by an index provider are generally included in the index. In general, broker-dealers value securities through their trading desks based on observable inputs. The methodologies include mapping securities based on trade data, bids or offers, observed spreads, and performance on newly issued securities. Broker-dealers also determine valuations by observing secondary trading of similar securities. Prices obtained from broker quotations are considered non-binding, however they are based on observable inputs and by observing secondary trading of similar securities obtained from active, non-distressed markets. The Company considers these Level 2 inputs as they are corroborated with other market observable inputs. The techniques generally used to determine the fair value of the Company’s fixed maturity investments are detailed below by asset class. U.S. government and government agency U.S. government and government agency securities consist primarily of debt securities issued by the U.S. Treasury and mortgage pass-through agencies such as the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation and the Government National Mortgage Association. Fixed maturity investments included in U.S. government and government agency securities are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources and integrate other observations from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The fair value of each security is individually computed using analytical models which incorporate option adjusted spreads and other daily interest rate data. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Non-U.S. government and government agency Non-U.S. government and government agency securities consist of debt securities issued by non-U.S. governments and their agencies along with supranational organizations (also known as sovereign debt securities). Securities held in these sectors are primarily priced by pricing services who employ proprietary discounted cash flow models to value the securities. Key quantitative inputs for these models are daily observed benchmark curves for treasury, swap and high issuance credits. The pricing services then apply a credit spread for each security which is developed by in-depth and real time market analysis. For securities in which trade volume is low, the pricing services utilize data from more frequently traded securities with similar attributes. These models may also be supplemented by daily market and credit research for international markets. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. U.S. states, municipalities and political subdivisions The Company’s U.S. states, municipalities and political subdivisions portfolio contains debt securities issued by U.S. domiciled state and municipal entities. These securities are generally priced by independent pricing services using the techniques described for U.S. government and government agency securities described above. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Agency residential mortgage-backed securities The Company’s agency residential mortgage-backed investments are primarily priced by pricing services using a mortgage pool specific model which utilizes daily inputs from the active to be announced market which is very liquid, as well as the U.S. treasury market. The model also utilizes additional information, such as the weighted average maturity, weighted average coupon and other available pool level data which is provided by the sponsoring agency. Valuations are also corroborated with daily active market quotes. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Non-agency residential mortgage-backed securities The Company’s non-agency mortgage-backed investments include non-agency prime residential mortgage-backed fixed maturity investments. The Company has no fixed maturity investments classified as sub-prime held in its fixed maturity investments portfolio. Securities held in these sectors are primarily priced by pricing services using an option adjusted spread model or other relevant models, which principally utilize inputs including benchmark yields, available trade information or broker quotes, and issuer spreads. The pricing services also review collateral prepayment speeds, loss severity and delinquencies among other collateral performance indicators for the securities valuation, when applicable. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. U.S. corporate Corporate debt securities consist primarily of investment-grade debt of a wide variety of U.S. corporate issuers and industries. The Company’s corporate fixed maturity investments are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources regarding the issuer of the security and obtain credit data, as well as other observations, from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The pricing services also consider the specific terms and conditions of the securities, including any specific features which may influence risk. In certain instances, securities are individually evaluated using a spread which is added to the U.S. treasury curve or a security specific swap curve as appropriate. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Non-U.S. corporate Non-U.S. corporate debt securities consist primarily of investment-grade debt of a wide variety of non-U.S. corporate issuers and industries. The Company’s non-U.S. corporate fixed maturity investments are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources regarding the issuer of the security and obtain credit data, as well as other observations, from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The pricing services also consider the specific terms and conditions of the securities, including any specific features which may influence risk. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Bank loans The Company’s bank loan investments consist primarily of below-investment-grade debt of a wide variety of corporate issuers and industries. The Company’s bank loans are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources regarding the issuer of the security and obtain credit data, as well as other observations, from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The pricing services also consider the specific terms and conditions of the securities, including any specific features which may influence risk. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Included in the bank loan portfolio is a collection of loan participations held through an intermediary. A third party pricing service provides monthly valuation reports for each loan and participation using a combination of quotations from loan pricing services, leveraged loan indices or market price quotes obtained directly from the intermediary. Significant unobservable inputs used to price these securities include credit spreads and default rates; therefore, the fair value of these investments are classified as Level 3. Asset-backed securities Asset backed securities include mostly investment-grade debt securities backed by pools of loans with a variety of underlying collateral, including automobile loan receivables, student loans, credit card receivables, and collateralized loan obligations originated by a variety of financial institutions. Securities held in these sectors are primarily priced by pricing services. The pricing services apply dealer quotes and other available trade information such as bids and offers, prepayment speeds which may be adjusted for the underlying collateral or current price data, the U.S. treasury curve and swap curve as well as cash settlement. The pricing services determine the expected cash flows for each security held in this sector using historical prepayment and default projections for the underlying collateral and current market data. In addition, a spread is applied to the relevant benchmark and used to discount the cash flows noted above to determine the fair value of the securities held in this sector. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Where pricing is unavailable from pricing services, we value the positions using alternative methods such as a discounted cash flow methodology. This is generally the case when there is a low volume of trading activity and/or current transactions are not orderly. Such discounted cash flow models for which significant observable inputs are unable to be corroborated with market observable information are classified as Level 3. Commercial mortgage-backed securities Commercial mortgage backed securities are investment-grade debt primarily priced by pricing services. The pricing services apply dealer quotes and other available trade information such as bids and offers, prepayment speeds which may be adjusted for the underlying collateral or current price data, the U.S. treasury curve and swap curve as well as cash settlement. The pricing services determine the expected cash flows for each security held in this sector using historical prepayment and default projections for the underlying collateral and current market data. In addition, a spread is applied to the relevant benchmark and used to discount the cash flows noted above to determine the fair value of the securities held in this sector. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Catastrophe bonds Catastrophe bonds are priced based on broker or underwriter bid indications. As the significant inputs used to price these securities are observable, the fair value of these investments are classified as Level 2. Where the significant inputs used to price these securities are unobservable, the fair value of these investments are classified as Level 3. Short-term investments Short-term investments consist primarily of highly liquid securities, all with maturities of less than one year from the date of purchase. The fair value of the portfolio is generally determined using amortized cost which approximates fair value. As the highly liquid money market-type funds are actively traded, the fair value of these investments are classified as Level 1. To the extent that the remaining securities are not actively traded due to their approaching maturity, the fair value of these investments are classified as Level 2. Other investments Fund of hedge funds The fund of hedge funds includes a side pocket. While a redemption request has been submitted, the timing of receipt of proceeds on the side pocket is unknown. The fund’s administrator provides a monthly reported NAV with a three month delay in its valuation. The fund manager has provided an estimate of the fund NAV at year end based on the estimated performance provided from the underlying funds. To determine the reasonableness of the estimated NAV, the Company compares the fund administrator’s NAV to the fund manager’s estimated NAV that incorporates relevant valuation sources on a timely basis. Material variances are recorded in the current reporting period while immaterial variances are recorded in the following reporting period. The fair value of these investments are measured using the NAV practical expedient and therefore have not been categorized within the fair value hierarchy. Hedge funds The hedge fund investment was assumed by the Company in its acquisition of Flagstone Reinsurance Holdings, S.A. (“Flagstone”) (the “Flagstone hedge fund”). The Flagstone hedge fund’s administrator provides quarterly NAVs with a three month delay in valuation. The fair value of this investment is measured using the NAV practical expedient and therefore has not been categorized within the fair value hierarchy. Private equity investments The private equity funds provide quarterly or semi-annual partnership capital statements with a three or six month delay which are used as a basis for valuation. These private equity investments vary in investment strategies and are not actively traded in any open markets. The fair value of these investments are measured using the NAV practical expedient and therefore have not been categorized within the fair value hierarchy. Fixed income investment funds The Company’s investment funds classified as Level 2 consist of a pooled investment fund. The pooled investment is invested in fixed income securities with high credit ratings and is only open to Lloyd’s Trust Fund participants. The fair value of units in the investment fund is based on the NAV of the fund and is traded on a daily basis. Included in investment funds is a residual equity tranche of a structured credit fund valued using a dynamic yield that calculates an income accrual based on an underlying valuation model with a typical cash flow waterfall structure. Significant unobservable inputs used to price this fund include default rates and prepayment rates; therefore, the fair value of the investment fund is classified as Level 3. The fair value of the Company’s remaining investment funds is based on the NAV of the fund as reported by the independent fund administrator. The fund’s administrators provide a monthly reported NAV with a one or three month delay in their valuation. The fair value of these investments are measured using the NAV practical expedient and therefore have not been categorized within the fair value hierarchy. Overseas deposits The Company’s share of a portfolio of Lloyd’s overseas deposits are managed centrally by Lloyd’s and invested according to local regulatory requirements. The composition of the portfolio varies and the deposits are made across the market. The fair value of the deposits is based on the portfolio level reporting that is provided by Lloyd’s. The fair value of these investments are measured using the NAV practical expedient and therefore have not been categorized within the fair value hierarchy. Mutual funds Mutual funds consist of an investment fund which invests in various quoted investments. The fair value of units in the mutual fund is based on the NAV of the fund as reported by the fund manager. The mutual fund has daily liquidity which allows us to redeem our holdings at the applicable NAV in the near term. As such, the Company has classified this investment as Level 2. (c) Level 3 investments The following table presents a reconciliation of the beginning and ending balances for all investments measured at fair value on a recurring basis using Level 3 inputs during the years ended December 31, 2016 and 2015 : Year Ended December 31, 2016 Bank Loans Catastrophe Bonds Fixed Income Investment Funds Asset Backed Securities Total Level 3 investments, beginning of year $ 232,337 $ 13,500 $ — $ — $ 245,837 Purchases 87,345 33,272 12,168 23,896 156,681 Sales (2,389 ) — — — (2,389 ) Settlements (69,496 ) (125 ) — — (69,621 ) Change in net unrealized (losses) gains (1,301 ) 1,728 — 35 462 Level 3 investments, end of year $ 246,496 $ 48,375 $ 12,168 $ 23,931 $ 330,970 Year Ended December 31, 2015 Bank Loans Catastrophe Bonds Total Level 3 investments, beginning of year $ 32,748 $ 17,500 $ 50,248 Purchases 230,070 — 230,070 Sales (1,036 ) (3,989 ) (5,025 ) Settlements (27,429 ) — (27,429 ) Net realized losses — (11 ) (11 ) Change in net unrealized losses (2,016 ) — (2,016 ) Level 3 investments, end of year $ 232,337 $ 13,500 $ 245,837 There were no transfers into or out of Level 3 during the years ended December 31, 2016 or 2015. (d) Financial instruments not carried at fair value ASC Topic 825 “Financial Instruments” is also applicable to disclosures of financial instruments not carried at fair value, except for certain financial instruments, including insurance contracts and investments in affiliates. The carrying values of cash and cash equivalents, restricted cash, accrued investment income, other assets, net payable for investments purchased and accounts payable and accrued expenses approximated their fair values at December 31, 2016 , due to their respective short maturities. As these financial instruments are not actively traded, their respective fair values are classified within Level 2.

Variable interest entities

Variable interest entities	12 Months Ended
	Dec. 31, 2016
Variable Interest Entities Disclosure [Abstract]
Variable interest entities	Variable interest entities The Company consolidates all VOEs in which it has a controlling financial interest and all VIEs in which it is considered to be the primary beneficiary. The Company’s VIEs primarily include entities related to the AlphaCat segment. (a) Consolidated VIEs AlphaCat sidecars Beginning on May 25, 2011 , the Company joined with other investors in capitalizing a series of sidecars for the purpose of investing in collateralized reinsurance and retrocessional contracts. Certain of these sidecars deployed their capital through transactions entered into by AlphaCat Reinsurance Ltd. (“AlphaCat Re”). Each of these entities return capital once the risk period expires and all losses have been paid out. The AlphaCat sidecars are VIEs and are consolidated by the Company as the primary beneficiary. The Company’s maximum exposure to any of the sidecars is the amount of capital invested at any given time. AlphaCat ILS funds The AlphaCat ILS funds received third party subscriptions beginning on December 17, 2012 . The Company and third party investors invest in the AlphaCat ILS funds for the purpose of investing in instruments with returns linked to property catastrophe reinsurance, retrocession and ILS contracts. The AlphaCat ILS funds have varying risk profiles and are categorized by the expected loss of the fund. Expected loss represents the average annual loss over the set of simulation scenarios divided by the total limit. Lower risk ILS funds are defined as having a maximum permitted portfolio expected loss of less than 7% , whereas higher risk ILS funds have a maximum permitted portfolio expected loss of greater than 7% . The AlphaCat ILS funds primarily deploy their capital through transactions entered into by AlphaCat Re and AlphaCat Master Fund Ltd. (“AlphaCat Master Fund”). The AlphaCat ILS funds are VIEs and are consolidated by the Company as the primary beneficiary. The Company’s maximum exposure to any of the funds is the amount of capital invested at any given time and any remaining capital commitments. Refer to Note 23 , “Commitments and contingencies,” for further details. AlphaCat Re and AlphaCat Master Fund The Company utilizes AlphaCat Re and AlphaCat Master Fund (collectively the “master funds”), both market facing entities, for the purpose of writing collateralized reinsurance and investing in capital markets products, respectively, on behalf of certain entities within the AlphaCat segment and direct third party investors. AlphaCat Re enters into transactions on behalf of the AlphaCat sidecars and ILS funds (collectively the “feeder funds”) and direct third party investors, whereas AlphaCat Master Fund only enters into transactions on behalf of certain AlphaCat ILS funds. All of the risks and rewards of the underlying transactions are allocated to the feeder funds and direct third party investors using variable funding notes. The master funds are VIEs and are consolidated by the Company as the primary beneficiary. Notes Payable to AlphaCat Investors The master funds issue variable funding notes to the feeder funds, and direct to third party investors, in order to write collateralized reinsurance and invest in capital markets products on their behalf. The Company’s investments in the feeder funds, together with investments made by third parties in the feeder funds and on a direct basis, are provided as consideration for the notes to the master funds. The duration of the underlying collateralized reinsurance contracts and capital market products is typically twelve months; however, the variable funding notes do not have a stated maturity date or principal amount since repayment is dependent on the settlement and income or loss of the underlying transactions. Therefore, the notes are subsequently redeemed as the underlying transactions are settled. The income or loss generated by the underlying transactions is then transferred to the feeder funds and direct third party investors via the variable funding notes. As both the master and feeder funds are consolidated by the Company, any notes issued by the master funds to the feeder funds are eliminated on consolidation and only variable funding notes issued by AlphaCat Re to direct third party investors remain on the Consolidated Balance Sheets as notes payable to AlphaCat investors with the related income or loss included in the Consolidated Statements of Income and Comprehensive Income as (income) attributable to AlphaCat investors. To the extent that the (income) loss has not been returned to the investors, it is included in accounts payable and accrued expenses in the Consolidated Balance Sheets. During 2016 , one of the AlphaCat ILS funds (“the Fund”) issued both common shares and structured notes to the Company and other third party investors in order to capitalize the fund. The Fund deploys its capital through AlphaCat Re; therefore, the structured notes do not have a stated maturity date or principal amount since repayment is dependent on the settlement and income or loss of the variable funding notes with AlphaCat Re. The structured notes rank senior to the common shares and earn an interest rate of 8.0% per annum, payable on a cumulative basis in arrears. As the Fund is consolidated by the Company, the structured notes issued to the Company are eliminated on consolidation and only the structured notes issued to third party investors remain on the Consolidated Balance Sheets as notes payable to AlphaCat investors with any related interest included in the Consolidated Statements of Income and Comprehensive Income as (income) loss attributable to AlphaCat investors. To the extent that the accrued interest on the structured notes has not been returned to the investors, it is included in accounts payable and accrued expenses in the Consolidated Balance Sheets. The following tables present a reconciliation of the beginning and ending notes payable to AlphaCat investors as at December 31, 2016 and 2015: Year Ended December 31, 2016 Variable Funding Notes Structured Notes Total Notes payable to AlphaCat investors, beginning of year $ 75,493 $ — $ 75,493 Issuance of notes payable to AlphaCat investors 311,711 94,326 406,037 Redemption of notes payable to AlphaCat investors (109,712 ) (94,326 ) (204,038 ) Foreign exchange gains 710 — 710 Notes payable to AlphaCat investors, end of year $ 278,202 $ — $ 278,202 Year Ended December 31, 2015 Variable Funding Notes Structured Notes Total Notes payable to AlphaCat investors, beginning of year $ — $ — $ — Issuance of notes payable to AlphaCat investors 75,770 — 75,770 Foreign exchange losses (277 ) — (277 ) Notes payable to AlphaCat investors, end of year $ 75,493 $ — $ 75,493 As at December 31, 2016 , $1,000 of the structured notes redeemed during the year ended December 31, 2016 were payable to AlphaCat investors and included in accounts payable and accrued expenses. The income attributable to AlphaCat investors for the year ended December 31, 2016 was $23,358 ( 2015 : $2,412 ), of which $17,068 was included in accounts payable and accrued expenses as at December 31, 2016 (December 31, 2015: $2,412 ). BetaCat ILS funds The BetaCat ILS funds invest exclusively in catastrophe bonds (principal-at-risk variable rate notes and other event-linked securities, being referred to collectively as “Cat Bonds”) focused on property and casualty risk and issued under Rule 144A of the Securities Act of 1933, as amended, following a passive buy-and-hold investment strategy. One of the funds is a VIE and is consolidated by the Company as the primary beneficiary. The remaining funds are VOEs and are consolidated by the Company as it owns all of the voting equity interests. The Company’s maximum exposure to any of the funds is the amount of capital invested at any given time. The following table presents the total assets and total liabilities of the Company’s consolidated VIEs, excluding intercompany eliminations, as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Total Assets Total Liabilities Total Assets Total Liabilities AlphaCat sidecars $ 40,041 $ 3,206 $ 206,581 $ 14,804 AlphaCat ILS funds - Lower Risk $ 1,498,276 $ 42,457 $ 1,268,070 $ 143,371 AlphaCat ILS funds - Higher Risk $ 972,633 $ 381,332 $ 522,867 $ 300,122 AlphaCat Re and AlphaCat Master Fund $ 2,510,415 $ 2,510,245 $ 1,615,779 $ 1,615,609 BetaCat ILS funds $ 82,471 $ 30,663 $ 64,221 $ 2,472 Assets of consolidated VIEs can only be used to settle obligations and liabilities of the consolidated VIEs and do not have recourse to the general credit of the Company. Investments of these entities are presented separately in Note 7 , “ Investments, ” as non-managed investments. (b) Non-Consolidated VIEs The Company invests in private equity and other investment vehicles as part of the Company’s investment portfolio. The activities of these VIEs are generally limited to holding investments and the Company’s involvement in these entities is passive in nature. The Company’s maximum exposure to the VIEs is the amount of capital invested at any given time and any remaining capital commitments. The Company does not have the power to direct the activities which most significantly impact the VIEs economic performance and therefore, the Company is not the primary beneficiary of these VIEs.

Noncontrolling interests

Noncontrolling interests	12 Months Ended
	Dec. 31, 2016
Noncontrolling Interest [Abstract]
Noncontrolling interest	Noncontrolling interests Investors in certain of the AlphaCat ILS funds have rights that enable shareholders, subject to certain limitations, to redeem their shares. The third party equity is therefore recorded on the Company’s Consolidated Balance Sheets as redeemable noncontrolling interests. When and if a redemption notice is received, the fair value of the redemption is reclassified to a liability. The AlphaCat sidecars and one of the AlphaCat ILS funds have no shareholder redemption rights. Therefore, the third party equity is recorded on the Company’s Consolidated Balance Sheets as noncontrolling interests. The following tables present a reconciliation of the beginning and ending balances of redeemable noncontrolling interests and noncontrolling interests for the years ended December 31, 2016 and 2015 : Redeemable Noncontrolling Interests Noncontrolling Interests Total Years Ended December 31, Years Ended December 31, Years Ended December 31, 2016 2015 2016 2015 2016 2015 Balance, beginning of year $ 1,111,714 $ 617,791 $ 154,662 $ 292,274 $ 1,266,376 $ 910,065 Issuance of shares 393,450 499,200 171,674 9,600 565,124 508,800 Income attributable to noncontrolling interests 100,852 71,418 22,511 21,546 123,363 92,964 Redemption of shares / Distributions (78,015 ) (76,695 ) (182,870 ) (168,758 ) (260,885 ) (245,453 ) Balance, end of year $ 1,528,001 $ 1,111,714 $ 165,977 $ 154,662 $ 1,693,978 $ 1,266,376 As at December 31, 2016 , redemptions of $71,530 and distributions of $16,144 (December 31, 2015: $10,800 and $ nil ) were payable to redeemable noncontrolling interests and noncontrolling interests, respectively. These amounts are classified within accounts payable and accrued expenses on the Company’s Consolidated Balance Sheets.

Investment in operating affilia

Investment in operating affiliate	12 Months Ended
	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Investment in affiliates	Investment in operating affiliate On April 2, 2012 , the Company joined with other investors in capitalizing PaCRe, Ltd. (“PaCRe”), a Class 4 Bermuda reinsurer formed for the purpose of writing high excess property catastrophe reinsurance. During 2015, PaCRe’s Class 4 license was surrendered and it was considered off-risk effective January 1, 2016. During 2016, PaCRe was liquidated. The Company’s investment in PaCRe was treated as an equity method investment. The following table presents a reconciliation of the beginning and ending investment in PaCRe for the years ended December 31, 2016 and 2015 : Years Ended December 31, 2016 2015 Operating affiliate, beginning of year $ 392 $ 50,944 Return of investment (369 ) (46,603 ) Loss from operating affiliate (23 ) (3,949 ) Operating affiliate, end of year $ — $ 392 The following table presents the Company’s investment in PaCRe as at December 31, 2015 : Investment at cost Voting ownership % Equity ownership % Carrying value Investment in PaCRe $ 392 100.0 % 10.0 % $ 392

Derivative instruments

Derivative instruments	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative instruments	Derivative instruments The Company enters into derivative instruments for risk management purposes, specifically to hedge unmatched foreign currency exposures and interest rate exposures. (a) Derivatives not designated as hedging instruments The following table summarizes information on the classification and amount of the fair value of derivatives not designated as hedging instruments for accounting purposes within the Company’s Consolidated Balance Sheets as at December 31, 2016 and December 31, 2015 : December 31, 2016 December 31, 2015 Derivatives not designated as hedging instruments Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Foreign currency forward contracts $ 181,375 $ 2,351 $ 3,421 $ 255,840 $ 2,601 $ 3,211 (a) Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses, respectively, within the Company’s Consolidated Balance Sheets. The following table summarizes information on the classification and net impact on earnings, recognized in the Company’s Consolidated Statements of Income and Comprehensive Income relating to the foreign currency forward and interest rate swap contracts that were not designated as hedging instruments for accounting purposes during the years ended December 31, 2016 , 2015 and 2014 : Derivatives not designated as hedging instruments Classification of gains (losses) recognized in earnings Years Ended December 31, 2016 2015 2014 Foreign currency forward contracts Foreign exchange gains losses $ (1,667 ) $ (610 ) $ — Foreign currency forward contracts Other insurance related income and other income $ 142 $ 139 $ (133 ) Interest rate swap contracts (a) Net realized gains on investments $ 8,518 $ — $ — (a) Relates to net realized gains on two interest rate swap contracts which were entered into and terminated during the year ended December 31, 2016 to partially offset the impact of interest rate increases on the Company’s fixed maturity investment portfolio. (b) Derivatives designated as hedging instruments The following table summarizes information on the classification and amount of the fair value of derivatives designated as hedging instruments for accounting purposes on the Consolidated Balance Sheets as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Derivatives designated as hedging instruments Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Interest rate swap contracts $ 552,263 $ 20 $ 1,479 $ 552,263 $ 21 $ 1,942 (a) Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses, respectively, within the Company’s Consolidated Balance Sheets. Derivative instruments designated as a fair value hedge Up to September 30, 2015, the Company had designated certain foreign currency derivative instruments as fair value hedges for accounting purposes and formally and contemporaneously documented all relationships between the derivative instruments and hedged items and linked the derivative instruments to specific assets and liabilities. The Company assessed the effectiveness of these hedges, both at inception and on an on-going basis to determine whether the hedges were highly effective in offsetting changes in fair value of the linked hedged items. The following table provides the net impact on earnings, recognized in income within foreign exchange gains (losses), relating to the derivative instruments formally designated as fair value hedges for accounting purposes along with the impact of the related hedged items for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, Foreign currency forward contracts 2016 2015 2014 Amount of loss recognized in income on derivative $ — $ (12,279 ) $ (9,651 ) Amount of gain on hedged item recognized in income attributable to risk being hedged $ — $ 12,279 $ 9,651 Amount of gain recognized in income on derivative (ineffective portion) $ — $ — $ — Derivative instruments designated as a cash flow hedge The Company designates its interest rate derivative instruments as cash flow hedges for accounting purposes and formally and contemporaneously documents all relationships between the hedging instruments and hedged items and links the derivative instruments to specific assets and liabilities. The Company assesses the effectiveness of the hedges, both at inception and on an on-going basis and determines whether the hedges are highly effective in offsetting changes in fair value of the linked hedged items. The Company currently applies the long haul method when assessing the hedge’s effectiveness. The following table provides the total impact on other comprehensive income (loss) and earnings relating to the derivative instruments formally designated as cash flow hedges along with the impact of the related hedged items for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, Interest rate swap contracts 2016 2015 2014 Amount of effective portion recognized in other comprehensive income $ 10,584 $ 13,740 $ 13,302 Amount of effective portion subsequently reclassified to earnings $ (10,861 ) $ (12,899 ) $ (13,074 ) Amount of ineffective portion excluded from effectiveness testing $ 277 $ (841 ) $ (228 ) The above balances relate to interest payments and have therefore been classified as finance expenses in the Consolidated Statements of Income and Comprehensive Income. (c) Classification within the fair value hierarchy As described in Note 8, “ Fair value measurements ,” a company must determine the appropriate level in the fair value hierarchy for each fair value measurement. The assumptions used within the valuation of the Company’s derivative instruments are observable in the marketplace, can be derived from observable data or are supported by observable levels at which other similar transactions are executed in the marketplace. Accordingly, these derivatives were classified within Level 2 of the fair value hierarchy. (d) Balance sheet offsetting There was no balance sheet offsetting activity as at December 31, 2016 or December 31, 2015 . The Company currently provides cash collateral as security for interest rate swap contracts. The Company does not provide cash collateral or financial instruments as security for foreign currency forward contracts. Our derivative instruments are generally traded under International Swaps and Derivatives Association master netting agreements, which establish terms that apply to all transactions. On a periodic basis, the amounts receivable from or payable to the counterparties are settled in cash. The Company has not elected to settle multiple transactions with an individual counterparty on a net basis.

Premiums receivable

Premiums receivable	12 Months Ended
	Dec. 31, 2016
Premiums Receivable Disclosure [Abstract]
Premiums receivable	Premiums receivable Premiums receivable are composed of premiums in the course of collection, net of commissions and brokerage, and premiums accrued but unbilled, net of commissions and brokerage. It is common practice in the (re)insurance industry for premiums to be paid on an installment basis, therefore significant amounts will be considered unbilled and will not become due until a future date, which is typically no later than expiration of the underlying coverage period. The following is a breakdown of the components of premiums receivable at December 31, 2016 and 2015 : Year Ended December 31, 2016 Premiums in course of collection Premiums accrued but unbilled Total Premiums receivable, beginning of year $ 95,152 $ 563,530 $ 658,682 Change during year 6,250 60,458 66,708 Premiums receivable, end of year $ 101,402 $ 623,988 $ 725,390 Year Ended December 31, 2015 Premiums in course of collection Premiums accrued but unbilled Total Premiums receivable, beginning of year $ 84,901 $ 621,566 $ 706,467 Change during year 10,251 (58,036 ) (47,785 ) Premiums receivable, end of year $ 95,152 $ 563,530 $ 658,682

Reserve for losses and loss exp

Reserve for losses and loss expenses	12 Months Ended
	Dec. 31, 2016
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Reserve for losses and loss expenses	Reserve for losses and loss expenses Reserves for losses and loss expenses are based in part upon the estimation of case reserves from broker, insured and ceding company reported data. The Company also uses statistical and actuarial methods to estimate ultimate expected losses and loss expenses, from which IBNR losses can be calculated. The period of time from the occurrence of a loss to the reporting of a loss to the Company and to the settlement of the Company’s liability may be several months or years. During this period, additional facts and trends may be revealed. As these factors become apparent, reserves will be adjusted, sometimes requiring an increase or decrease in the overall reserves of the Company, and at other times requiring a reallocation of incurred but not reported reserves to specific case reserves. These estimates are reviewed and adjusted regularly, and such adjustments, if any, are reflected in earnings in the period in which they become known. While management believes that it has made a reasonable estimate of ultimate losses, there can be no assurances that ultimate losses and loss expenses will not exceed this estimate. The following table summarizes the total reserve for losses and loss expenses as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Case reserves $ 1,237,772 $ 1,278,697 IBNR 1,757,423 1,717,870 Total reserve for losses and loss expenses $ 2,995,195 $ 2,996,567 The following table represents an analysis of paid and unpaid losses and loss expenses incurred and a reconciliation of the beginning and ending unpaid losses and loss expenses for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Reserve for losses and loss expenses, beginning of year $ 2,996,567 $ 3,243,147 $ 3,047,933 Loss reserves recoverable (350,586 ) (377,466 ) (370,154 ) Net reserves for losses and loss expenses, beginning of year 2,645,981 2,865,681 2,677,779 Net reserves acquired — — 525,091 Increase (decrease) in net reserves for losses and loss expenses in respect of losses occurring in: Current year 1,281,289 1,283,970 1,024,256 Prior years (a) (216,192 ) (306,137 ) (259,241 ) Total incurred losses and loss expenses (a) 1,065,097 977,833 765,015 Less net losses and loss expenses paid in respect of losses occurring in: Current year (389,234 ) (326,167 ) (245,084 ) Prior years (725,168 ) (841,672 ) (818,569 ) Total net paid losses (1,114,402 ) (1,167,839 ) (1,063,653 ) Foreign exchange gain (31,902 ) (29,694 ) (38,551 ) Net reserve for losses and loss expenses, end of year 2,564,774 2,645,981 2,865,681 Loss reserves recoverable 430,421 350,586 377,466 Reserve for losses and loss expenses, end of year $ 2,995,195 $ 2,996,567 $ 3,243,147 Incurred losses and loss expenses comprise: Years Ended December 31, 2016 2015 2014 Gross losses and loss expenses (a) $ 1,257,054 $ 1,083,695 $ 826,826 Reinsurance balances recoverable (191,957 ) (105,862 ) (61,811 ) Net incurred losses and loss expenses (a) $ 1,065,097 $ 977,833 $ 765,015 (a) Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was fully amortized to income through a reduction in losses and loss expenses of $10,979 and $4,607 during the years ended December 31, 2015 and 2014, respectively. The net favorable development on prior accident years by segment and line of business for the years ended December 31, 2016 , 2015 and 2014 was as follows: Year Ended December 31, 2016 Property Marine Specialty Liability Total Validus Re $ (57,888 ) $ (24,435 ) $ (36,210 ) $ — $ (118,533 ) Talbot (38,368 ) (11,738 ) (35,704 ) — (85,810 ) Western World (2,701 ) — — (6,411 ) (9,112 ) AlphaCat (1,858 ) — (879 ) — (2,737 ) Net favorable development $ (100,815 ) $ (36,173 ) $ (72,793 ) $ (6,411 ) $ (216,192 ) The Validus Re segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses along with favorable development on the 2015 Chilean Earthquake and 2015 Tianjin port explosion loss events partially offset by adverse development on events in the marine lines primarily related to receipt of a loss advice on an individual marine policy that incepted during the second half of 2015. The Talbot segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses partially offset by adverse development on events in the marine lines primarily related to receipt of a loss advice on an individual marine policy that incepted during the second half of 2015. The Western World segment experienced favorable development on prior accident years principally due to favorable development on attritional losses. Year Ended December 31, 2015 Property Marine Specialty Liability Total (a) Validus Re $ (70,343 ) $ (39,460 ) $ (18,813 ) $ — $ (128,616 ) Talbot (52,393 ) (63,920 ) (30,044 ) — (146,357 ) Western World (a) (6,045 ) — — (16,922 ) (22,967 ) AlphaCat (8,197 ) — — — (8,197 ) Net favorable development (a) $ (136,978 ) $ (103,380 ) $ (48,857 ) $ (16,922 ) $ (306,137 ) The Validus Re segment experienced favorable development on prior accident years primarily due to favorable development on Superstorm Sandy, a 2012 loss event, and attritional losses. The Talbot segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses and certain events, including the Thailand floods, which was a 2011 loss event. The Western World segment experienced favorable development on prior accident years primarily due to the amortization of the fair value adjustment made at the acquisition date as well as favorable development on attritional losses. Year Ended December 31, 2014 Property Marine Specialty Liability Total Validus Re $ (76,064 ) $ (6,830 ) $ (4,706 ) $ — $ (87,600 ) Talbot (53,779 ) (31,397 ) (55,990 ) — (141,166 ) Western World (a) 1,023 — — (12,263 ) (11,240 ) AlphaCat (19,235 ) — — — (19,235 ) Net favorable development (a) $ (148,055 ) $ (38,227 ) $ (60,696 ) $ (12,263 ) $ (259,241 ) (a) Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was fully amortized to income through a reduction in losses and loss expenses of $10,979 and $4,607 during the years ended December 31, 2015 and 2014, respectively. The Validus Re segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses and the European Floods, Superstorm Sandy and Gryphon Alpha mooring failure loss events, partially offset by adverse development on the Costa Concordia loss event. The Talbot segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses and loss events, primarily the Tohoku earthquake, which was a 2011 loss event. The Western World segment experienced favorable development on prior accident years primarily due to the amortization of the fair value adjustment made at the acquisition date as well as favorable development on attritional losses. The AlphaCat segment experienced favorable development on prior accident years primarily due to the partial release of a 2013 aggregate excess of loss contract. Short Duration Contract Disclosures During the year, the Company adopted ASU 2015-09 and has included the required disclosures below. Refer to Note 4, “Recent Accounting Pronouncements,” for further information. The Company has disaggregated its information presented in the tables below by line of business as appropriate for each of the Validus Re, Talbot and Western World segments. The Company has not prepared loss development tables for the AlphaCat segment as its reserves for losses and loss expenses as at December 31, 2016 of $48,534 are not significant ( 1.9% of total net reserves) and therefore, presenting this information would not be meaningful. Reserves for the AlphaCat segment have been included as a reconciling item within the reconciliation of loss development information to the Company’s reserves for losses and loss expenses. The Company has presented the below development tables for all accident years shown using exchange rates as at December 31, 2016. All accident years prior to the current year have been restated and presented using the current year exchange rate. (a) Loss Development Tables (i) Validus Re The Validus Re loss development tables have been produced by line of business for accident years 2012 through to 2016. The Company determined that it was impracticable to produce IBNR by accident year by lines of business for years prior to 2012 as the necessary data in original currency was not readily available. In addition, Validus Re provides treaty reinsurance products on a global basis for all of its lines of business and does not receive or maintain claims count information associated with its reserved claims. As such, the Company has determined that it is impracticable to provide this information. The net reserves for losses and loss expenses related to the acquisitions of IPC Holdings Ltd. (“IPC”) acquired on September 4, 2009, and Flagstone Reinsurance Holdings, S.A. (“Flagstone”), acquired on November 30, 2012, have been incorporated in Validus Re’s reserves for losses and loss expenses on a prospective basis. IPC and Flagstone were put into run-off as at the acquisition date of each. The prospective treatment for the acquisition of Flagstone was adopted primarily as a result of the data necessary to produce the loss development tables by accident year and by lines of business not being migrated over on acquisition as it was not requested or received and as a result does not exist within Validus Re’s data systems. Validus Re - Property Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 397,635 $ 321,956 $ 309,344 $ 282,517 $ 280,411 $ 19,108 n/a 2013 174,722 156,233 141,203 132,830 7,233 n/a 2014 108,206 102,273 95,392 6,757 n/a 2015 154,923 118,484 41,177 n/a 2016 149,263 86,564 n/a Total $ 776,380 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 67,004 149,433 202,141 225,518 234,256 2013 17,325 63,974 101,158 114,263 2014 25,346 63,415 78,509 2015 16,029 57,882 2016 26,522 Total $ 511,432 Reserves for losses and loss expenses, before 2012, net of reinsurance (a) $ 154,539 Reserves for losses and loss expenses, net of reinsurance $ 419,487 (a) Includes reserves for losses and loss expenses, net of reinsurance, of $77,790 and $10,614 related to Flagstone and IPC, respectively. Validus Re - Marine Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 195,163 $ 226,817 $ 225,131 $ 218,734 $ 216,673 $ 19,725 n/a 2013 76,776 74,022 63,630 61,210 7,347 n/a 2014 63,732 42,991 35,910 7,418 n/a 2015 129,864 119,490 55,557 n/a 2016 68,531 49,619 n/a Total $ 501,814 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 11,356 94,052 148,628 169,420 178,172 2013 11,784 28,996 39,493 44,512 2014 7,013 11,749 17,383 2015 3,723 16,180 2016 8,801 Total $ 265,048 Reserves for losses and loss expenses, before 2012, net of reinsurance (a) $ 64,750 Reserves for losses and loss expenses, net of reinsurance $ 301,516 (a) Includes reserves for losses and loss expenses, net of reinsurance, of $15,178 and $1,537 related to Flagstone and IPC, respectively. Validus Re - Specialty Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 53,798 $ 54,573 $ 49,263 $ 47,428 $ 46,626 $ 733 n/a 2013 182,297 190,470 178,736 174,219 1,974 n/a 2014 213,911 208,508 200,649 8,372 n/a 2015 296,554 279,766 32,236 n/a 2016 295,872 128,761 n/a Total $ 997,132 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 17,716 $ 41,156 $ 44,037 $ 44,942 $ 45,332 2013 99,340 157,688 164,366 166,814 2014 95,765 162,056 176,202 2015 177,776 235,819 2016 149,502 Total $ 773,669 Reserves for losses and loss expenses, before 2012, net of reinsurance (a) $ 67,909 Reserves for losses and loss expenses, net of reinsurance $ 291,372 (a) Includes reserves for losses and loss expenses, net of reinsurance, of $41,091 and $5,743 related to Flagstone and IPC, respectively. (ii) Talbot The Talbot loss development tables have been produced by line of business for accident years 2012 through to 2016. The Company determined that it was impracticable to produce IBNR by accident year for years prior to 2012 as the Company did not record this data for years prior to 2012 and as such, did not allocate IBNR by line of business for these years. Talbot writes treaty reinsurance business along with business through binders and lineslips and for this business the Company does not receive or maintain claims count information associated with its reserved losses therefore, the Company has determined that it is impracticable to provide claims count information. Talbot - Property Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 135,923 $ 112,488 $ 100,748 $ 101,387 $ 100,773 $ 2,413 n/a 2013 118,167 96,814 83,426 81,004 605 n/a 2014 147,259 121,260 114,852 5,528 n/a 2015 138,087 109,608 12,696 n/a 2016 177,771 76,755 n/a Total $ 584,008 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 13,051 $ 61,490 $ 83,824 $ 88,150 $ 92,512 2013 12,813 48,231 67,328 73,267 2014 21,249 74,493 95,945 2015 24,537 63,437 2016 37,880 Total $ 363,041 Reserves for losses and loss expenses, before 2012, net of reinsurance $ 12,180 Reserves for losses and loss expenses, net of reinsurance $ 233,147 Talbot - Marine Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 208,883 $ 203,855 $ 186,278 $ 182,283 $ 178,839 $ 5,154 n/a 2013 189,091 188,991 168,203 161,839 11,372 n/a 2014 180,401 155,361 154,105 13,671 n/a 2015 187,790 192,818 54,285 n/a 2016 159,153 89,536 n/a Total $ 846,754 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 36,491 $ 105,600 $ 136,335 $ 153,550 $ 157,475 2013 38,416 88,494 112,781 125,037 2014 24,433 74,547 102,788 2015 25,300 73,957 2016 35,105 Total $ 494,362 Reserves for losses and loss expenses, before 2012, net of reinsurance $ 44,753 Reserves for losses and loss expenses, net of reinsurance $ 397,145 Talbot - Specialty Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 151,306 $ 132,735 $ 122,760 $ 120,621 $ 118,869 $ 5,886 n/a 2013 166,450 145,905 132,797 124,208 8,724 n/a 2014 215,960 214,962 198,653 39,248 n/a 2015 152,907 149,031 39,447 n/a 2016 166,604 105,142 n/a Total $ 757,365 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 25,591 $ 57,906 $ 83,201 $ 87,753 $ 105,888 2013 42,325 77,428 91,940 100,213 2014 41,183 107,882 135,526 2015 35,724 85,397 2016 33,468 Total $ 460,492 Reserves for losses and loss expenses, before 2012, net of reinsurance $ 45,486 Reserves for losses and loss expenses, net of reinsurance $ 342,359 (iii) Western World The Western World loss development tables have been produced by line of business for accident years 2007 through to 2016. The Company has accumulated claims count information by accident year for Western World. The Company’s methodology for determining reported claims count information is on a per claims basis by accident year and is inclusive of claims that are open, closed with payment and closed without payment. Western World - Property Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 8,520 $ 8,161 $ 8,218 $ 8,209 $ 8,209 $ 8,206 $ 8,206 $ 8,207 $ 8,207 $ 8,207 $ — 841 2008 12,094 11,615 11,805 11,762 11,729 11,721 11,724 11,724 11,724 — 412 2009 10,300 10,005 10,039 10,034 10,060 10,060 10,060 10,060 — 784 2010 11,846 11,573 11,507 11,414 11,448 11,438 11,332 — 974 2011 12,588 12,223 12,000 12,134 12,012 12,021 — 1,238 2012 15,506 15,491 15,594 15,556 15,522 — 1,680 2013 21,825 23,561 23,659 23,599 — 1,950 2014 35,612 29,282 28,619 103 2,393 2015 27,879 26,002 135 1,788 2016 46,636 9,324 1,587 Total $ 193,722 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 5,418 $ 7,968 $ 8,192 $ 8,206 $ 8,206 $ 8,206 $ 8,206 $ 8,207 $ 8,207 $ 8,207 2008 8,895 11,288 11,672 11,747 11,714 11,721 11,724 11,724 11,724 2009 8,096 9,948 9,942 10,003 10,060 10,060 10,060 10,060 2010 8,563 10,521 10,905 10,854 10,882 10,903 11,287 2011 9,797 12,000 11,976 12,027 12,009 12,021 2012 11,166 14,838 15,435 15,513 15,522 2013 15,568 22,647 23,104 23,561 2014 21,913 27,211 27,606 2015 18,981 25,302 2016 29,666 Total $ 174,956 Reserves for losses and loss expenses, before 2007, net of reinsurance $ — Reserves for losses and loss expenses, net of reinsurance $ 18,766 Western World - Liability Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 164,717 $ 162,239 $ 160,117 $ 158,478 $ 154,499 $ 152,163 $ 149,994 $ 107,894 $ 107,350 $ 106,342 $ 1,981 $ 4.727 2008 135,009 135,280 135,330 133,088 131,006 129,559 102,424 102,070 101,478 2,075 4,950 2009 116,474 116,780 116,990 116,463 116,327 98,261 96,235 95,266 2,173 3,955 2010 101,223 108,823 111,675 112,072 105,400 106,066 103,973 3,877 4,205 2011 101,091 107,741 107,827 109,412 109,183 108,301 4,627 4,372 2012 108,981 111,283 133,990 132,562 127,486 9,410 4,649 2013 132,077 165,233 164,428 158,329 17,049 5,990 2014 197,022 197,388 203,592 44,988 7,469 2015 154,184 158,591 76,092 5,152 2016 133,303 104,906 3,156 Total $ 1,296,661 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 10,723 $ 30,741 $ 58,358 $ 80,218 $ 91,020 $ 96,658 $ 99,978 $ 102,600 $ 103,961 $ 104,038 2008 8,654 28,467 51,165 71,239 82,661 89,433 93,563 95,773 97,475 2009 10,023 30,131 48,255 65,009 77,895 85,644 89,688 90,415 2010 8,215 28,393 51,765 71,430 84,320 92,889 96,309 2011 7,331 27,438 50,197 75,000 88,415 96,780 2012 8,823 31,291 65,437 92,499 108,409 2013 10,159 41,782 77,776 108,613 2014 16,468 52,543 98,848 2015 12,662 39,598 2016 9,873 Total $ 850,358 Reserves for losses and loss expenses, before 2007, net of reinsurance $ 8,944 Reserves for losses and loss expenses, net of reinsurance $ 455,247 (b) Reconciliation of Loss Development Information to the Reserves for Losses and Loss Expenses The table below reconciles the loss development information to the Company’s reserves for losses and loss expenses as at December 31, 2016: December 31, 2016 Reserves for losses and loss expenses, net of reinsurance Validus Re - Property $ 419,487 Validus Re - Marine 301,516 Validus Re - Specialty 291,372 Talbot - Property 233,147 Talbot - Marine 397,145 Talbot - Specialty 342,359 Western World - Property 18,766 Western World - Liability 455,247 Total reserves for losses and loss expenses, net of reinsurance 2,459,039 Loss reserves recoverable Validus Re - Property 42,873 Validus Re - Marine 52,970 Validus Re - Specialty 2,162 Talbot - Property 93,774 Talbot - Marine 125,677 Talbot - Specialty 86,587 Western World - Property 187 Western World - Liability 87,300 Elimination - Intercompany (61,109 ) Total loss reserves recoverable 430,421 Unallocated loss adjustment expenses 51,990 Provisions for uncollectible reinsurance 5,153 Reserves for losses and loss expenses - AlphaCat segment 48,534 Other 58 Total reserves for losses and loss expenses $ 2,995,195 (c) Historical Loss Duration The below table summarizes the historic average annual percentage payout of incurred losses by age, net of reinsurance, as of December 31, 2016: Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance December 31, 2016 Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Year 9 Year 10 Validus Re - Property 19.0 % 34.9 % 20.9 % 9.1 % 3.1 % n/a n/a n/a n/a n/a Validus Re - Marine 12.0 % 22.5 % 19.3 % 8.9 % 4.0 % n/a n/a n/a n/a n/a Validus Re - Specialty 51.4 % 34.4 % 5.7 % 1.7 % 0.8 % n/a n/a n/a n/a n/a Talbot - Property 18.2 % 43.4 % 21.5 % 5.8 % 4.3 % n/a n/a n/a n/a n/a Talbot - Marine 19.0 % 31.8 % 16.8 % 8.6 % 2.2 % n/a n/a n/a n/a n/a Talbot - Specialty 24.1 % 30.6 % 15.6 % 5.2 % 15.3 % n/a n/a n/a n/a n/a Western World - Property 73.1 % 22.4 % 2.0 % 0.5 % 0.1 % 0.1 % 0.9 % — % — % — % Western World - Liability 8.1 % 18.9 % 22.9 % 20.1 % 12.0 % 7.2 % 3.7 % 1.8 % 1.5 % 0.1 %

Accounts payable and accrued ex

Accounts payable and accrued expenses	12 Months Ended
	Dec. 31, 2016
Accounts Payable and Accrued Liabilities [Abstract]
Accounts payable and accrued expenses	Accounts payable and accrued expenses The following are the components of accounts payable and accrued expenses: December 31, 2016 December 31, 2015 Accrued interest on debt $ 10,286 $ 10,771 Subscriptions received in advance on AlphaCat ILS funds and sidecars 326,900 412,036 Redemptions/distributions payable to noncontrolling interests 87,674 10,800 Structured notes payable to AlphaCat investors 1,000 — Accrued income attributable to AlphaCat investors 17,068 2,412 Income tax payable 1,036 8,856 Accrued pension liability 16,979 15,722 Trade and compensation payables 126,705 166,734 Total accounts payable and accrued expenses $ 587,648 $ 627,331 For the year ended December 31, 2016, non-cash movements in accounts payable and accrued expenses in relation to the AlphaCat ILS funds and sidecars were $217,322 (2015: $(10,239) ; 2014: $7,847 ). Of this, redemptions/distributions payable to noncontrolling interests included non-cash movements of $77,873 (2015: $(10,239) ; 2014: $7,847 ). Subscriptions received in advance on AlphaCat ILS funds and sidecars included non-cash reinvestment of noncontrolling interests and structured notes of $139,449 (2015: $ nil ; 2014: $ nil ).

Reinsurance

Reinsurance	12 Months Ended
	Dec. 31, 2016
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance The Company’s reinsurance balances recoverable at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Loss reserves recoverable on unpaid: Case reserves $ 165,328 $ 135,723 IBNR 265,093 214,863 Total loss reserves recoverable 430,421 350,586 Paid losses recoverable 35,247 23,071 Total reinsurance recoverable $ 465,668 $ 373,657 The Company enters into reinsurance and retrocession agreements in order to mitigate its accumulation of loss, reduce its liability on individual risks, enable it to underwrite policies with higher limits and increase its aggregate capacity. The cession of insurance and reinsurance does not legally discharge the Company from its primary liability for the full amount of the policies, and the Company is required to pay the loss and bear collection risk if the reinsurer fails to meet its obligations under the reinsurance or retrocession agreement. Amounts recoverable from reinsurers are estimated in a manner consistent with the underlying liabilities. (a) Effects of reinsurance on premiums written and earned The effects of reinsurance on premiums written and earned for the years ended December 31, 2016 , 2015 and 2014 were as follows: Year Ended December 31, 2016 Validus Re Talbot Western World AlphaCat Eliminations Total Written Earned Written Earned Written Earned Written Earned Written Earned Written Earned Treaty reinsurance $ 1,111,054 $ 1,060,117 $ 146,296 $ 115,828 $ — $ — $ 270,402 $ 256,085 $ (26,673 ) $ (23,035 ) $ 1,501,079 $ 1,408,995 Facultative reinsurance — — 293,741 307,351 — — — — — — 293,741 307,351 Direct — — 530,665 529,265 323,220 294,376 — — — — 853,885 823,641 Ceded (111,564 ) (116,172 ) (175,729 ) (170,528 ) (22,634 ) (21,144 ) (6,451 ) (6,013 ) 26,673 23,035 (289,705 ) (290,822 ) Total $ 999,490 $ 943,945 $ 794,973 $ 781,916 $ 300,586 $ 273,232 $ 263,951 $ 250,072 $ — $ — $ 2,359,000 $ 2,249,165 Year Ended December 31, 2015 Validus Re Talbot Western World AlphaCat Eliminations Total Written Earned Written Earned Written Earned Written Earned Written Earned Written Earned Treaty reinsurance $ 1,126,759 $ 1,141,184 $ 133,273 $ 136,796 $ — $ — $ 176,126 $ 164,544 $ (42,718 ) $ (45,115 ) $ 1,393,440 $ 1,397,409 Facultative reinsurance — — 325,311 330,472 — — — — — — 325,311 330,472 Direct — — 560,251 570,669 278,504 281,587 — — — — 838,755 852,256 Ceded (149,088 ) (150,971 ) (198,896 ) (199,846 ) (18,877 ) (22,937 ) (4,538 ) (4,609 ) 42,718 45,115 (328,681 ) (333,248 ) Total $ 977,671 $ 990,213 $ 819,939 $ 838,091 $ 259,627 $ 258,650 $ 171,588 $ 159,935 $ — $ — $ 2,228,825 $ 2,246,889 Year Ended December 31, 2014 Validus Re Talbot Western World AlphaCat Eliminations Total Written Earned Written Earned Written Earned Written Earned Written Earned Written Earned Treaty reinsurance $ 1,118,532 $ 1,109,659 $ 149,079 $ 163,382 $ — $ — $ 126,785 $ 126,534 $ (53,457 ) $ (60,912 ) $ 1,340,939 $ 1,338,663 Facultative reinsurance — — 334,898 345,252 — — — — — — 334,898 345,252 Direct — — 617,793 576,136 65,235 80,838 — — — — 683,028 656,974 Ceded (163,678 ) (192,375 ) (192,211 ) (204,996 ) (6,428 ) (7,842 ) (4,348 ) (3,533 ) 53,457 60,912 (313,208 ) (347,834 ) Total $ 954,854 $ 917,284 $ 909,559 $ 879,774 $ 58,807 $ 72,996 $ 122,437 $ 123,001 $ — $ — $ 2,045,657 $ 1,993,055 (b) Credit risk The Company evaluates the financial condition of its reinsurers and monitors concentration of credit risk arising from its exposure to individual reinsurers. The reinsurance program is generally placed with reinsurers whose rating, at the time of placement, was A- or better as rated by Standard & Poor’s or the equivalent with other rating agencies. Exposure to a single reinsurer is also controlled with restrictions dependent on rating. As at December 31, 2016 , $461,369 or 99.1% ( December 31, 2015 : $368,638 or 98.7% ) of the Company’s reinsurance balances recoverable were either fully collateralized or recoverable from reinsurers rated A- or better. Reinsurance recoverables by reinsurer as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Reinsurance Recoverable % of Total Reinsurance Recoverable % of Total Top 10 reinsurers $ 395,308 84.9 % $ 303,108 81.1 % Other reinsurers’ balances > $1 million 66,944 14.4 % 61,222 16.4 % Other reinsurers’ balances < $1 million 3,416 0.7 % 9,327 2.5 % Total $ 465,668 100.0 % $ 373,657 100.0 % December 31, 2016 Top 10 Reinsurers Rating Reinsurance Recoverable % of Total Lloyd's Syndicates A+ $ 84,419 18.2 % Swiss Re AA- 84,044 18.1 % Fully collateralized reinsurers NR 83,088 17.8 % Hannover Re AA- 50,603 10.9 % Everest Re A+ 36,912 7.9 % Munich Re AA- 18,214 3.9 % Transatlantic Re A+ 10,593 2.3 % Hamilton Re A- 10,343 2.2 % Toa Re A+ 9,510 2.0 % National Indemnity Company AA+ 7,582 1.6 % Total $ 395,308 84.9 % NR: Not rated December 31, 2015 Top 10 Reinsurers Rating Reinsurance Recoverable % of Total Swiss Re AA- $ 83,048 22.2 % Lloyd's Syndicates A+ 66,356 17.8 % Hannover Re AA- 43,765 11.7 % Everest Re A+ 43,060 11.5 % Munich Re AA- 18,707 5.0 % Transatlantic Re A+ 11,923 3.2 % Hamilton Re A- 10,898 2.9 % National Indemnity Company AA+ 10,293 2.8 % XL Re A+ 8,728 2.3 % Toa Re A+ 6,330 1.7 % Total $ 303,108 81.1 % At December 31, 2016 and 2015 , the provision for uncollectible reinsurance relating to reinsurance recoverables was $5,153 and $4,997 , respectively. To estimate this provision for uncollectible reinsurance, reinsurance recoverables are first allocated to applicable reinsurers. This determination is based on a process rather than an estimate, although an element of judgment is applied, especially in relation to ceded IBNR. The Company then uses default factors to determine the portion of a reinsurer’s balance deemed to be uncollectible. Default factors require considerable judgment and are determined in part using the current rating, or rating equivalent, of each reinsurer as well as other key considerations and assumptions.

Share capital

Share capital	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Note [Abstract]
Share capital	Share capital The Company is authorized to issue up to an aggregate of 571,428,571 common and preferred shares with a par value of $0.175 per share. (a) Preferred shares On June 13, 2016, the Company issued 6,000 shares of its 5.875% Non-Cumulative Preferred Shares, Series A (the “Series A Preferred Shares”) (equivalent to 6,000,000 Depositary Shares, each of which represents a 1/1,000th interest in a Series A Preferred Share), $0.175 par value and $25,000 liquidation preference per share (equivalent to $25 per Depositary Share). The Series A Preferred Shares were registered and sold under the Securities Act of 1933, as amended, and were issued at a price to the public of $25,000 per share (equivalent to $25 per Depositary Share). After underwriting discounts and expenses, the Company received net proceeds of $144,852 which will be used for general corporate purposes. The Depositary Shares, representing the Series A Preferred Shares, are traded on the New York Stock Exchange under the symbol “VRPRA.” The Series A Preferred Shares have no stated maturity date and are redeemable, in whole or in part, at the Company’s option on and after June 15, 2021, at a redemption price of $25,000 per Series A Preferred Share (equivalent to $25 per Depositary Share), plus declared and unpaid dividends. The Company may also redeem all, but not less than all, of the Series A Preferred Shares before the redemption date at a redemption price of $26,000 per share (equivalent to $26 per Depositary Share), plus declared and unpaid dividends, if the Company is required to submit a proposal to the holders of the Series A Preferred Shares concerning an amalgamation, consolidation, merger or other similar corporate transaction or change in Bermuda law. The Series A Preferred Shares may also be redeemed before the redemption date at a redemption price of $25,000 per Series A Preferred Share (equivalent to $25 per Depositary Share), plus declared and unpaid dividends, in whole, if there is a change in tax law, or in whole or in part, in the case of a capital disqualification event. Dividends on the Series A Preferred Shares, when, as and if declared by the Company’s Board of Directors or a duly authorized committee thereof, will accrue and be payable on the liquidation preference amount from the original issue date, on a non-cumulative basis, quarterly in arrears on each dividend payment date at an annual rate of 5.875% . The Company will be restricted from paying dividends on and repurchasing its common shares, unless certain dividend payments are made on the Series A Preferred Shares. Upon any voluntary or involuntary liquidation, dissolution or winding up of the Company, holders of the Series A Preferred Shares and any parity shares are entitled to receive out of the Company’s assets available for distribution to shareholders, before any distribution is made to holders of common shares or other junior shares, a liquidating distribution in the amount of $25,000 per Series A Preferred Share (equivalent to $25 per Depositary Share) plus declared and unpaid dividends. Distributions will be made pro rata in accordance with the respective aggregate liquidation preferences of the Series A Preferred Shares and any parity shares and only to the extent of our assets, if any, that are available after satisfaction of all liabilities to creditors. Holders of the Series A Preferred Shares have no voting rights, except with respect to certain fundamental changes in the terms of the Series A Preferred Shares and in the case of certain dividend non-payments or as otherwise required by Bermuda law or the Company’s bye-laws. The following table is a summary of the Preferred shares issued and outstanding: Preferred Shares Preferred shares issued and outstanding, beginning of year — Preferred shares issued 6,000 Preferred shares issued and outstanding, end of year 6,000 (b) Common shares The holders of common shares are entitled to receive dividends and are allocated one vote per share , provided that, if the controlled shares of any shareholder or group of related shareholders constitute more than 9.09 percent of the outstanding common shares of the Company, their voting power will be reduced to 9.09 percent. The Company may from time to time repurchase its securities, including common shares, Junior Subordinated Deferrable Debentures and Senior Notes. On February 3, 2015, the Board of Directors of the Company approved an increase in the Company’s common share repurchase authorization to $750,000 . This amount was in addition to the $2,274,401 of common shares repurchased by the Company through February 3, 2015 under its previously authorized share repurchase programs. The Company has repurchased approximately 80,508,849 common shares for an aggregate purchase price of $2,704,406 from the inception of its share repurchase program to December 31, 2016 . The Company had $319,995 remaining under its authorized share repurchase program as of December 31, 2016 . The Company expects the purchases under its share repurchase program to be made from time to time in the open market or in privately negotiated transactions. The timing, form and amount of the share repurchases under the program will depend on a variety of factors, including market conditions, the Company’s capital position relative to internal and rating agency targets, legal requirements and other factors. The repurchase program may be modified, extended or terminated by the Board of Directors at any time. The following table is a summary of the common shares issued and outstanding during the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Common shares issued, beginning of year 160,570,772 155,554,224 154,488,497 Restricted share awards vested, net of shares withheld 612,100 614,945 615,659 Restricted share units vested, net of shares withheld 18,486 13,260 10,265 Options exercised 30,530 782,465 412,656 Warrants exercised — 3,593,715 — Direct issuance of common stock — 639 1,380 Performance shares vested, net of shares withheld 48,088 11,524 25,767 Common shares issued, end of year 161,279,976 160,570,772 155,554,224 Treasury shares, end of year (82,147,724 ) (77,670,155 ) (71,684,379 ) Common shares outstanding, end of year 79,132,252 82,900,617 83,869,845 (c) Warrants The Company had no outstanding warrants as at both December 31, 2016 and 2015 . During the year ended December 31, 2015 , 5,154,077 warrants were exercised, while 20,037 warrants expired without being exercised. Each warrant provided the holder with the option to purchase a common share at a specified exercise price. All outstanding warrants expired on December 12, 2015 and no further warrants are anticipated to be issued. The warrants were settled using either the physical settlement or net-share settlement methods. The warrants have been classified as equity instruments, in accordance with ASC Topic 815 “Derivatives and Hedging, Contracts in Entity’s own Equity.” The warrants were measured at fair value and recorded in additional paid-in capital. (d) Dividends The Company announced four quarterly cash dividends of $0.35 per common share during the year ended December 31, 2016 ( 2015 : $0.32 ). These dividends were paid on March 31, 2016 , June 30, 2016 , September 30, 2016 and December 30, 2016 to holders of record on March 15, 2016 , June 15, 2016 , September 15, 2016 and December 15, 2016 , respectively. During the quarter ended September 30, 2016, the Company declared and paid a cash dividend on its outstanding Series A Preferred Shares of $0.3753472 per depositary share for the period June 13, 2016 to September 15, 2016. In addition, during the quarter ended December 31, 2016, the Company declared and paid a cash dividend of $0.3671875 per depositary share. These dividends were paid on September 15, 2016 and December 15, 2016, to holders of record on September 1, 2016 and December 1, 2016, respectively.

Stock plans

Stock plans	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock plans	Stock plans (a) Long Term Incentive Plan The Company’s Amended and Restated 2005 Long Term Incentive Plan (“LTIP”) provides for grants to employees of options, stock appreciation rights (“SARs”), restricted shares, restricted share units, performance shares, dividend equivalents or other share-based awards. The total number of shares reserved for issuance under the LTIP are 2,753,292 shares of which 1,251,411 shares are remaining. The LTIP is administered by the Compensation Committee of the Board of Directors. No SARs have been granted to date. Grant prices are established at the fair market value of the Company’s common shares at the date of grant. (i) Options Options may be exercised for voting common shares upon vesting. Options have a life of 10 years and vest either pro rata or at the end of the required service period from the date of grant. Fair value of the option awards at the date of grant is determined using the Black-Scholes option-pricing model. Expected volatility is based on stock price volatility of comparable publicly-traded companies. The Company used the simplified method consistent with U.S. GAAP authoritative guidance on stock compensation expenses to estimate expected lives for options granted during the period as historical exercise data was not available and the options met the requirement as set out in the guidance. The Company has not granted any stock option awards since September 4, 2009. These stock option awards were fully amortized during the year ended December 31, 2012. Activity with respect to options for the year ended December 31, 2016 was as follows: Options Weighted Average Grant Date Fair Value Weighted Average Grant Date Exercise Price Total Intrinsic Value (a) Company Proceeds Received Options outstanding, beginning of year 65,401 $ 7.74 $ 20.17 Options exercised (39,265 ) 8.37 17.96 $ 1,260 $ 277 Options outstanding, end of year 26,136 $ 6.78 $ 23.48 Activity with respect to options for the year ended December 31, 2015 was as follows: Options Weighted Average Grant Date Fair Value Weighted Average Grant Date Exercise Price Total Intrinsic Value (a) Company Proceeds Received Options outstanding, beginning of year 1,160,057 $ 7.12 $ 17.74 Options exercised (1,094,656 ) 7.09 17.60 $ 26,367 $ 6,277 Options outstanding, end of year 65,401 $ 7.74 $ 20.17 Activity with respect to options for the year ended December 31, 2014 was as follows: Options Weighted Average Grant Date Fair Value Weighted Average Grant Date Exercise Price Total Intrinsic Value (a) Company Proceeds Received Options outstanding, beginning of year 1,572,713 $ 6.66 $ 18.88 Options exercised (412,656 ) 5.36 22.07 $ 7,459 $ 9,107 Options outstanding, end of year 1,160,057 $ 7.12 $ 17.74 (a) The total intrinsic value in the tables above represent the amount by which the market price of the Company’s common stock is greater than the option strike price multiplied by the number of options exercised during the year. There have been no unamortized share compensation expenses in respect of options since the year ended December 31, 2012. The aggregate intrinsic value of the options outstanding and exercisable at December 31, 2016 was $831 (December 31, 2015: $1,740 ). (ii) Restricted share awards Restricted shares granted under the LTIP vest either pro rata or at the end of the required service period and contain certain restrictions during the vesting period, relating to, among other things, forfeiture in the event of termination of employment and transferability. Share compensation expenses of $36,887 were recorded for the year ended December 31, 2016 ( 2015 : $35,386 ; 2014 : $31,335 ). The expenses represent the proportionate accrual of the fair value of each grant based on the remaining vesting period. Activity with respect to unvested restricted share awards for the years ended December 31, 2016, 2015 and 2014 was as follows: Years Ended December 31, 2016 2015 2014 Restricted Share Awards Weighted Average Grant Date Fair Value Restricted Share Awards Weighted Average Grant Date Fair Value Restricted Share Awards Weighted Average Grant Date Fair Value Restricted share awards outstanding, beginning of year 2,739,446 $ 38.25 2,858,711 $ 35.81 2,684,745 $ 33.74 Restricted share awards granted 564,345 48.83 724,357 43.67 1,051,348 37.81 Restricted share awards vested (796,716 ) 37.40 (788,758 ) 34.41 (797,446 ) 31.44 Restricted share awards forfeited (37,093 ) 41.27 (54,864 ) 38.14 (79,936 ) 36.09 Restricted share awards outstanding, end of year 2,469,982 $ 40.89 2,739,446 $ 38.25 2,858,711 $ 35.81 At December 31, 2016 , there were $58,804 (December 31, 2015 : $69,143 ) of total unrecognized share compensation expenses in respect of restricted share awards that are expected to be recognized over a weighted-average period of 2.3 years (December 31, 2015 : 2.4 years). (iii) Restricted share units Restricted share units under the LTIP vest either ratably or at the end of the required service period and contain certain restrictions during the vesting period, relating to, among other things, forfeiture in the event of termination of employment and transferability. Share compensation expenses of $1,285 were recorded for the year ended December 31, 2016 ( 2015 : $1,160 ; 2014 : $876 ). The expenses represent the proportionate accrual of the fair value of each grant based on the remaining vesting period. Activity with respect to unvested restricted share units for the years ended December 31, 2016, 2015 and 2014 was as follows: Years Ended December 31, 2016 2015 2014 Restricted Share Units Weighted Average Grant Date Fair Value Restricted Share Units Weighted Average Grant Date Fair Value Restricted Share Units Weighted Average Grant Date Fair Value Restricted share units outstanding, beginning of year 114,337 $ 38.47 103,484 $ 36.54 66,518 $ 33.74 Restricted share units granted 27,609 50.03 28,057 42.91 53,025 38.10 Restricted share units vested (23,982 ) 38.18 (19,455 ) 34.58 (18,325 ) 30.71 Restricted share units issued in lieu of cash dividends 3,182 39.36 3,143 37.53 2,266 35.00 Restricted share units forfeited (8,338 ) 44.34 (892 ) 35.42 — — Restricted share units outstanding, end of year 112,808 $ 40.95 114,337 $ 38.47 103,484 $ 36.54 At December 31, 2016 , there were $2,542 (December 31, 2015 : $2,790 ) of total unrecognized share compensation expenses in respect of restricted share units that are expected to be recognized over a weighted-average period of 2.6 years (December 31, 2015 : 2.6 years). (iv) Performance share awards The performance share awards contain a performance based component. The performance component relates to the compounded growth in the Dividend Adjusted Book Value per Diluted Share (“DBVPS”) over a three year period. For performance share awards granted during the period, the grant date is based on the DBVPS at the end of the most recent financial reporting year. The performance period end DBVPS will be the DBVPS three years after the grant date DBVPS. The fair value estimate earns over the requisite attribution period and the estimate will be reassessed at the end of each performance period which will reflect any adjustments in the consolidated statements of comprehensive income in the period in which they are determined. Share compensation expenses of $4,735 were recorded for the year ended December 31, 2016 ( 2015 : $1,795 ; 2014 : $862 ). The share compensation expenses represent the proportionate accrual of the fair value of each grant based on the remaining vesting period. The negative expense is due to a reversal of expenses on unvested performance share awards based on a review of current and projected performance criteria. Activity with respect to unvested performance share awards for the years ended December 31, 2016, 2015, and 2014 was as follows: Years Ended December 31, 2016 2015 2014 Performance Share Awards Weighted Average Grant Date Fair Value Performance Share Awards Weighted Average Grant Date Fair Value Performance Share Awards Weighted Average Grant Date Fair Value Performance share awards outstanding, beginning of year 172,594 $ 40.70 106,369 $ 36.03 101,820 $ 33.56 Performance share awards granted 125,290 48.75 81,569 45.03 52,639 37.33 Performance share awards vested (57,581 ) 36.11 (15,344 ) 31.38 (32,746 ) 32.62 Performance share awards conversion adjustment 45,517 36.82 — — (15,344 ) 31.38 Performance share awards outstanding, end of year 285,820 $ 44.53 172,594 $ 40.70 106,369 $ 36.03 At December 31, 2016 , there were $6,902 (December 31, 2015 : $4,011 ) of total unrecognized share compensation expenses in respect of performance share awards that are expected to be recognized over a weighted-average period of 2.1 years (December 31, 2015 : 2.1 years ). (b) Total share compensation expenses The breakdown of share compensation expenses by award type is as follows: Years Ended December 31, 2016 2015 2014 Restricted share awards $ 36,887 $ 35,386 $ 31,335 Restricted share units 1,285 1,160 876 Performance share awards 4,735 1,795 862 Total $ 42,907 $ 38,341 $ 33,073 In addition, the Company recorded $1,869 of associated tax benefits for the year ended December 31, 2016 ( 2015 : $3,436 ; 2014 : $1,610 ). The Company also recognized $1,203 of net windfall taxes during the year ended December 31, 2016 ( 2015 : $906 ; 2014: $3,513 ) in relation to share vestings and option exercises.

Retirement and pension plans

Retirement and pension plans	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Retirement and pension plans	Retirement and pension plans (a) Defined benefit plans Senior executives and retired selected key employees of Western World participate in non-qualified, unfunded, defined benefit plans. Benefits for these plans are based on final average earnings, social security benefits earned at retirement date and years of service. The assumptions used to determine net periodic pension expense for the years ended December 31, 2016 and 2015 are as follows: Years Ended December 31, 2016 2015 Discount rate 3.50 % 2.75 % Increase in compensation levels rate 5.00 % 5.00 % The assumptions used to determine benefit obligations as at December 31, 2016 and 2015 are as follows: December 31, 2016 December 31, 2015 Discount rate 4.00 % 4.00 % Increase in compensation levels rate 5.00 % 5.00 % The following tables present a reconciliation of the beginning and ending funded status and the net amounts recognized for the defined benefit plans for the years ended December 31, 2016 and 2015 : Years Ended December 31, 2016 2015 Change in benefit obligation Projected benefit obligation, beginning of year $ 15,722 $ 16,493 Service cost 1,026 1,024 Interest cost 594 434 Actuarial losses (gains) 1,473 (46 ) Benefit payments (98 ) (98 ) Settlements (1,738 ) (2,085 ) Projected benefit obligation, end of year $ 16,979 $ 15,722 Change in plan assets Fair value of plan assets, beginning of year $ — $ — Employer contributions 1,836 2,186 Benefit payments (98 ) (98 ) Settlements (1,738 ) (2,088 ) Fair value of plan assets, end of year — — Funded status at end of year $ (16,979 ) $ (15,722 ) Net amount recognized in accounts payable and accrued expenses $ (16,979 ) $ (15,722 ) Amounts recognized in accumulated other comprehensive loss consist of Net loss (gain) $ 226 $ (517 ) Prior service credit 6 4 Net amount recognized $ 232 $ (513 ) December 31, 2016 December 31, 2015 Projected benefit obligation $ 16,979 $ 15,722 Accumulated benefit obligation $ 13,480 $ 13,308 Fair value of plan assets $ — $ — The components of net periodic pension expense for the years ended December 31, 2016 and 2015 are as follows: Years Ended December 31, 2016 2015 Service cost $ 1,026 $ 1,024 Interest cost 594 434 Amortization of prior service cost (2 ) (2 ) Amortization of net loss 374 312 Net periodic benefit cost 1,992 1,768 Settlement loss 356 484 Net periodic pension expense $ 2,348 $ 2,252 Other changes in plan assets and benefit obligations recognized in other comprehensive loss for the years ended December 31, 2016 and 2015 are as follows: Years Ended December 31, 2016 2015 Net loss (gain) $ 1,473 $ (43 ) Amortization of loss (374 ) (312 ) Amortization of prior service cost 2 2 Settlement loss (356 ) (484 ) Total recognized in other comprehensive loss $ 745 $ (837 ) Total recognized in net pension expense and other comprehensive loss (before tax effects) $ 3,093 $ 1,415 The estimated amount of net loss and prior service cost expected to be amortized from accumulated other comprehensive (loss) income into net periodic pension expense over the next fiscal year is $2 . The employer benefit payments/settlements for the year ended December 31, 2016 were $1,836 ( 2015 : $2,183 ). As at December 31, 2016 , the projected benefits are as follows: December 31, 2016 2017 $ 2,740 2018 7,072 2019 92 2020 2,665 2021 83 2022-2026 5,449 Total benefit payments required $ 18,101 (b) Other pension plans The Company provides pension benefits to eligible employees through various plans which are managed externally and sponsored by the Company. The Company’s contributions are expensed as incurred. The Company’s expenses for its defined contribution retirement plans for the years ended December 31, 2016 , 2015 and 2014 were $13,419 , $13,684 and $10,606 , respectively.

Debt and financing arrangements

Debt and financing arrangements	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Debt and financing arrangements	Debt and financing arrangements The Company’s financing structure consists of debentures and senior notes payable along with credit and other facilities. The Company’s outstanding debentures and senior notes payable as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Deferrable debentures 2006 Junior Subordinated $ 150,000 $ 150,000 2007 Junior Subordinated 139,800 139,800 Flagstone 2006 Junior Subordinated 133,676 134,118 Flagstone 2007 Junior Subordinated 113,750 113,750 Total debentures payable 537,226 537,668 2010 Senior notes payable 250,000 250,000 Less: Unamortized debt issuance costs (4,638 ) (4,839 ) Total senior notes payable 245,362 245,161 Total debentures and senior notes payable $ 782,588 $ 782,829 The Company’s outstanding credit and other facilities as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Commitment Drawn and outstanding Commitment Drawn and outstanding Credit and other facilities $85,000 syndicated unsecured letter of credit facility $ 85,000 $ — $ 85,000 $ — $300,000 syndicated secured letter of credit facility 300,000 90,252 300,000 235,540 $24,000 secured bi-lateral letter of credit facility 24,000 4,553 24,000 10,543 $20,000 AlphaCat Re secured letter of credit facility 20,000 20,000 30,000 30,000 $25,000 IPC bi-lateral facility 25,000 5,842 25,000 9,241 $236,000 Flagstone bi-lateral facility 236,000 144,392 236,000 193,764 Total credit and other facilities $ 690,000 $ 265,039 $ 700,000 $ 479,088 (a) Senior notes and junior subordinated deferrable debentures The following table summarizes the key terms of the Company’s senior notes and junior subordinated deferrable debentures: Description Issuance date Amount Maturity date Interest Rate as at Interest payments due Issuance Date December 31, 2016 2006 Junior Subordinated Deferrable Debentures June 15, 2006 $ 150,000 June 15, 2036 9.069 % (a) 5.831 % (e) Quarterly Flagstone 2006 Junior Subordinated Deferrable Debentures August 23, 2006 $ 133,676 September 15, 2036 3.540 % (b) 6.463 % (e) Quarterly 2007 Junior Subordinated Deferrable Debentures June 21, 2007 $ 200,000 June 15, 2037 8.480 % (c) 5.180 % (e) Quarterly Flagstone 2007 Junior Subordinated Deferrable Debentures June 8, 2007 $ 88,750 July 30, 2037 3.000 % (b) 5.900 % (e) Quarterly Flagstone 2007 Junior Subordinated Deferrable Debentures September 20, 2007 $ 25,000 September 15, 2037 3.100 % (b) 5.983 % (e) Quarterly 2010 Senior Notes due 2040 January 26, 2010 $ 250,000 January 26, 2040 8.875 % (d) 8.875 % (d) Semi-annually in arrears (a) Fixed interest rate for 5 years , floating interest rate of three-month LIBOR plus 3.550% thereafter, reset quarterly. (b) Floating interest rate of three-month LIBOR plus amount stated, reset quarterly. (c) Fixed interest rate for 5 years , floating interest rate of three-month LIBOR plus 2.950% thereafter, reset quarterly. (d) Fixed interest rate. (e) Fixed interest rate as a result of interest rate swap contracts entered into by the Company. Senior Notes The 2010 Senior Notes due 2040 (the “2010 Senior Notes”) were part of a registered public offering and mature on January 26, 2040. The Company may redeem the notes, in whole at any time, or in part from time to time, at the Company’s option on not less than 30 nor more than 60 days’ notice, at a make-whole redemption price as described in “Description of the Notes - Optional Redemption” in the 2010 Senior Notes prospectus supplement. In addition, the Company may redeem the notes, in whole, but not in part, at any time upon the occurrence of certain tax events as described in “Description of the Notes - Redemption for Tax Purposes” in the prospectus supplement. Debt issuance costs are amortized to income over the life of the 2010 Senior Notes and are presented on a net basis within the senior notes payable balance in the Company’s Consolidated Balance Sheets. There were no redemptions made during the year ended December 31, 2016 and 2015 . The 2010 Senior Notes are unsecured and unsubordinated obligations of the Company and rank equally in right of payment with all of the Company’s existing and future unsecured and unsubordinated indebtedness. The 2010 Senior Notes will be effectively junior to all of the Company’s future secured debt, to the extent of the value of the collateral securing such debt, and will rank senior to all our existing and future subordinated debt. The 2010 Senior Notes are structurally subordinated to all obligations of the Company’s subsidiaries. Future payments of principal of $250,000 on the 2010 Senior Notes are all expected to be after 2021. Junior subordinated deferrable debentures The Company participated in private placements of junior subordinated deferrable interest debentures due 2036 and 2037 (respectively, the “2006 Junior Subordinated Deferrable Debentures” and “2007 Junior Subordinated Deferrable Debentures”). Debt issuance costs for the 2006 and 2007 Junior Subordinated Deferrable Debentures were amortized to income over the five year optional redemption periods. They are redeemable at the Company’s option at par. There were no redemptions made during the year ended December 31, 2016 and 2015 . As part of the acquisition of Flagstone, the Company assumed junior subordinated deferrable debentures due 2036 and 2037 (respectively, the “Flagstone 2006 Junior Subordinated Deferrable Debentures” and “Flagstone 2007 Junior Subordinated Deferrable Debentures”). These debentures are redeemable quarterly at par. There were no redemptions made during the year ended December 31, 2016 and 2015 . Future payments of principal of $537,226 on the debentures discussed above are all expected to be after 2021. (b) Credit facilities (i) $85,000 syndicated unsecured letter of credit facility and $300,000 syndicated secured letter of credit facility On December 9, 2015 , the Company entered into a $85,000 five year unsecured facility with various counterparties as co-documentation agents and the lenders party thereto, which provides for letter of credit (“LOC”) and revolving credit availability for the Company (the “Five Year Unsecured Facility”) (the full $85,000 of which is available for LOC’s and/or revolving loans). The Five Year Unsecured Facility was provided by a syndicate of commercial banks. LOC’s under the Five Year Unsecured Facility are available to support obligations in connection with the reinsurance business of the Company and its subsidiaries. Loans under the Five Year Unsecured Facility are available for the general corporate and working capital purposes of the Company. The Company may request that existing lenders under the Five Year Unsecured Facility or prospective additional lenders agree to make available additional commitments from time to time so long as the aggregate commitments under the Five Year Unsecured Facility do not exceed $150,000 . Also on December 9, 2015 , the Company entered into a $300,000 five year secured credit facility, with the same parties, which provides for LOC availability for the Company (the “Five Year Secured Facility” and together with the Five Year Unsecured Facility, the “Credit Facilities”). The Five Year Secured Facility was also provided by a syndicate of commercial banks. LOC’s under the Five Year Secured Facility will be available to support obligations in connection with the reinsurance business of the Company and its subsidiaries. The Company may request that existing lenders under the Five Year Secured Facility or prospective additional lenders agree to make available additional commitments from time to time so long as the aggregate commitments under the Five Year Secured Facility do not exceed $400,000 . The obligations of the Company under the Five Year Secured Facility are secured by cash and securities deposited into cash collateral accounts from time to time with The Bank of New York Mellon. As of December 31, 2016 , there was $nil (December 31, 2015 : $nil ) of outstanding LOC’s under the Five Year Unsecured Facility and $90,252 (December 31, 2015 : $235,540 ) of outstanding LOC’s under the Five Year Secured Facility. The Credit Facilities contain covenants that include, among other things (i) the requirement that the Company initially maintain a minimum level of consolidated net worth of at least $2,600,000 and, commencing with the end of the fiscal quarter ending June 30, 2015, to be increased quarterly by an amount equal to 25.0% of the Company’s consolidated net income (if positive) for such quarter plus 50.0% of the aggregate increases in the consolidated shareholders’ equity of the Company during such fiscal quarter by reason of the issuance and sale of common equity interests of the Company, including upon any conversion of debt securities of the Company into such equity interests, (ii) the requirement that the Company maintain at all times a consolidated total debt to consolidated total capital ratio not greater than 0.35:1.00 , and (iii) the requirement that Validus Reinsurance, Ltd. and any other material insurance subsidiaries maintain a financial strength rating by A.M. Best of not less than “B++” (Fair). In addition, the Credit Facilities contain customary negative covenants applicable to the Company, including limitations on the ability to pay dividends and other payments in respect of equity interests at any time that the Company is otherwise in default with respect to certain provisions under the respective Credit Facilities, limitations on the ability to incur liens, sell assets, merge or consolidate with others, enter into transactions with affiliates, and limitations on the ability of its subsidiaries to incur indebtedness. The Credit Facilities also contain customary affirmative covenants, representations and warranties and events of default for credit facilities of its type. As of December 31, 2016 , and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the Credit Facilities. (ii) $25,000 IPC bi-lateral facility The Company assumed an existing evergreen LOC facility through the acquisition of IPC Holdings, Ltd. (the “IPC bi-lateral facility”). As of December 31, 2016 , there were $5,842 of outstanding LOC’s issued under the IPC bi-lateral facility (December 31, 2015 : $9,241 ). As of December 31, 2016 , and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the IPC bi-lateral facility. (iii) $24,000 secured bi-lateral letter of credit facility The Company is party to an evergreen secured bi-lateral LOC facility with Citibank Europe plc (the “Secured bi-lateral LOC facility”). As of December 31, 2016 , $4,553 (December 31, 2015 : $10,543 ) of LOC’s were outstanding under the Secured bi-lateral LOC facility. The Secured bi-lateral LOC facility has no fixed termination date and as of December 31, 2016 , and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the Secured bi-lateral LOC facility. (iv) $20,000 AlphaCat Re secured letter of credit facility During 2013, AlphaCat Re entered into a secured evergreen LOC facility with Comerica Bank. This facility provided for LOC’s issued by AlphaCat Re to be used to support its reinsurance obligations. During the second quarter of 2016 the available amount under this facility was reduced to $20,000 from $30,000 . As of December 31, 2016 , $20,000 (December 31, 2015 : $30,000 ) of LOC’s were outstanding under this facility. As of December 31, 2016 , and throughout the reporting periods presented, AlphaCat Re was in compliance with all covenants and restrictions under the AlphaCat Re secured LOC facility. (v) $236,000 Flagstone bi-lateral facility As part of the acquisition of Flagstone, the Company assumed an evergreen LOC Master Agreement between Citibank Europe plc and Flagstone Reassurance Suisse, S.A. (the “Flagstone Bi-Lateral Facility”). As of December 31, 2016 , the Flagstone Bi-Lateral Facility had $144,392 (December 31, 2015 : $193,764 ) of LOC’s issued and outstanding. As of December 31, 2016 , and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the Flagstone Bi-Lateral Facility. (vi) Investments and cash pledged as collateral The Company has pledged investments and cash as collateral under the Company’s credit facilities in the total amount of $442,184 (December 31, 2015 : $826,535 ) as detailed in the table below: December 31, 2016 December 31, 2015 $300,000 syndicated secured letter of credit facility $ 157,597 $ 370,909 $24,000 secured bi-lateral letter of credit facility 48,097 47,607 $20,000 AlphaCat Re secured letter of credit facility 20,032 30,153 $236,000 Flagstone bi-lateral facility 216,458 377,866 Total $ 442,184 $ 826,535 (c) Finance expenses Finance expenses consist of interest on the junior subordinated deferrable debentures and senior notes, the amortization of debt offering costs, credit facility fees, bank charges, Talbot Funds at Lloyds (“FAL”) facility costs, AlphaCat financing fees and other charges as follows: Years Ended December 31, 2016 2015 2014 2006 Junior Subordinated Deferrable Debentures $ 8,893 $ 8,868 $ 8,868 2007 Junior Subordinated Deferrable Debentures 7,362 7,341 7,341 Flagstone 2006 Junior Subordinated Deferrable Debentures 9,028 8,989 9,001 Flagstone 2007 Junior Subordinated Deferrable Debentures 7,100 7,123 7,129 2010 Senior Notes due 2040 22,388 22,388 22,388 Credit facilities 2,060 6,006 5,516 Bank charges, Talbot FAL facility and other charges (a) 504 4,592 4,536 AlphaCat fees (b) 1,185 9,435 3,545 Total finance expenses $ 58,520 $ 74,742 $ 68,324 (a) On November 30, 2015, the Company terminated its Talbot FAL Facility provided and arranged by Lloyds Bank plc and ING Bank N.V., London Branch. (b) Includes finance expenses incurred by AlphaCat Managers in relation to fund raising for the AlphaCat sidecars, the AlphaCat ILS funds and AlphaCat direct.

Income taxes

Income taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income taxes	Income taxes The Company provides for income taxes based upon amounts reported in the financial statements and the provisions of currently enacted tax laws. The Company is registered in Bermuda and is subject to Bermuda law with respect to taxation. Under current Bermuda law, the Company is not taxed on any Bermuda income or capital gains and has received an undertaking from the Bermuda Minister of Finance that, in the event of any Bermuda income or capital gains taxes being imposed, the Company will be exempt from such taxes until March 31, 2035. The Company has subsidiaries and branches with operations in several jurisdictions outside Bermuda, including but not limited to the U.K., U.S., Switzerland and Canada that are subject to relevant taxes in those jurisdictions. Within Note 26 , “Segment information,” gross premiums written are allocated to the territory of coverage exposure and therefore do not correlate to pre-tax income generated in any of the territories identified. The Company’s income (loss) before income taxes for the years ended December 31, 2016 , 2015 and 2014 was generated in the following domestic and foreign jurisdictions: Years Ended December 31, 2016 2015 2014 Domestic Bermuda $ 447,257 $ 470,454 $ 518,476 Foreign U.K. 4,308 13,621 10,824 U.S. 4,038 (4,176 ) (11,752 ) Switzerland (1,084 ) 2,276 9,941 Canada 2,599 493 2,773 Other 33,736 (2,074 ) 29,076 Total income before income taxes $ 490,854 $ 480,594 $ 559,338 Income tax (benefit) expense is comprised of both current and deferred tax attributable to U.S. and Non-U.S. jurisdictions as follows: Years Ended December 31, 2016 2015 2014 Current income tax expense U.S. $ 2,042 $ 739 $ 21,257 Non-U.S. 711 6,028 26,179 Total current income tax expense $ 2,753 $ 6,767 $ 47,436 Deferred income tax (benefit) expense U.S. $ (3,487 ) $ 1,360 $ (24,998 ) Non-U.S. (18,995 ) (1,751 ) (22,283 ) Total deferred income tax benefit $ (22,482 ) $ (391 ) $ (47,281 ) Total income tax (benefit) expense U.S. $ (1,445 ) $ 2,099 $ (3,741 ) Non-U.S. (18,284 ) 4,277 3,896 Total income tax (benefit) expense $ (19,729 ) $ 6,376 $ 155 The table below is a reconciliation of the actual income tax (benefit) expense for the years ended December 31, 2016 , 2015 and 2014 to the amount computed by applying the effective tax rate of 0% under Bermuda law to income before taxes: Years Ended December 31, 2016 2015 2014 Expected tax expense at Bermuda statutory rate of 0% $ — $ — $ — Foreign tax rate differential 11,394 6,462 7,993 Changes in valuation allowance (36,990 ) 9,830 (7,284 ) Tax exempt income and expenses not deductible (1,960 ) 393 (6,055 ) Share compensation tax windfall 1,203 906 3,513 Impact of enacted changes in tax rates 8,931 69 250 Prior years tax adjustments (5,199 ) (12,272 ) 666 Other 2,892 988 1,072 Actual income tax (benefit) expense $ (19,729 ) $ 6,376 $ 155 Deferred tax assets and liabilities primarily represent the tax effect of temporary differences between the carrying value of assets and liabilities for financial statement purposes and such values as measured by tax laws and regulations in countries in which the operations are taxable. Deferred tax assets may also represent the tax effect of tax losses carried forward. In assessing whether a deferred tax asset can be recovered and assessing the need for a valuation allowance, the Company considers all positive and negative evidence to determine whether it is more-likely-than-not that the tax benefit of part or all of a deferred tax asset will be realized. The Company’s framework for assessing the recoverability of deferred tax assets primarily considers taxable income in prior carryback years when permitted by law, future reversal of existing taxable temporary differences, available tax planning strategies and the expected occurrence of future taxable income. The weighting of the positive and negative evidence is commensurate with the extent to which they can be objectively verified. Significant components of the Company’s deferred tax assets and liabilities as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Deferred tax asset Tax losses carried forward $ 116,416 $ 167,929 Deferred compensation 6,915 7,504 Deferred interest expense 2,039 2,047 Tax credits carried forward 5,469 2,761 Discounting of loss reserves 9,938 11,882 Unearned premiums reserve 6,647 4,291 Pension 5,943 5,503 Lloyd’s underwriting loss deductible in future periods 581 47 Other 4,943 4,111 Deferred tax asset, gross of valuation allowance 158,891 206,075 Valuation allowance (98,065 ) (167,929 ) Net deferred tax asset $ 60,826 $ 38,146 Deferred tax liability Deferred acquisition costs 4,633 1,989 Intangibles 7,583 8,111 Unrealized appreciation on investments 3,179 7,073 Properties and fixed assets 2,593 2,044 Other 2,640 1,115 Deferred tax liability 20,628 20,332 Net deferred tax asset $ 40,198 $ 17,814 The movement in deferred tax asset on tax losses carried forward and related valuation allowance from December 31, 2015 to December 31, 2016 can be explained as follows: Deferred Tax Asset on Tax Losses Carried Forward Valuation Allowance Balance as at December 31, 2015 $ 167,929 $ (167,929 ) Movement due to use of tax losses carried forward (10,990 ) 10,990 Movement due to provision to return adjustments 1,108 (1,108 ) Movement due to changes in enacted tax rates (8,757 ) 8,757 Movement due to change in assessment of deferred tax asset recoverability — 18,351 Forfeiture of tax losses carried forward (32,927 ) 32,927 Other 53 (53 ) Balance as at December 31, 2016 $ 116,416 $ (98,065 ) The movement of $10,990 represents the tax benefit from the use of tax losses carried forward where a full valuation allowance was provided (Luxembourg: $6,722 ; U.S.: $3,066 ; and Singapore: $1,202 ). The movement of $1,108 represents prior year adjustments reflecting tax losses carried forward as per tax returns filed. The movement of $8,757 reflects the impact of enacted changes in income tax rates under Luxembourg law. The change in valuation allowance of $18,351 is due to the partial release of a valuation allowance which had previously been applied against a deferred tax asset related to carried forward Luxembourg tax losses acquired as part of the Flagstone acquisition. As of December 31, 2016, the Company believes, after review of all available positive and negative evidence, that it is more-likely-than-not to have sufficient future taxable income to realize a portion of that deferred tax asset. As such, the Company has recorded a partial release of the previously held valuation allowance resulting in a current year tax benefit. The tax effect from forfeiture of tax losses carried forward of $32,927 primarily results from $18,438 related to the closure of certain Luxembourg operations and $14,489 attributable to the reduction of Swiss tax losses associated with the application of non-taxable income of Validus Re Swiss’ Bermuda Branch in accordance with Swiss law. As at December 31, 2016 , the Company had net operating and capital losses carried forward, inclusive of cumulative currency translation adjustments, as follows: Tax Jurisdiction Losses carried forward Tax effect Expiration U.S. $ 11,195 $ 3,918 2029 - 2035 Switzerland $ 157,512 $ 33,078 2018 - 2020 Luxembourg $ 300,121 $ 78,310 None Singapore $ 11,090 $ 1,109 None The valuation allowance as at December 31, 2016 of $98,065 ( 2015 : $167,929 ) relates to tax losses carried forward of subsidiaries primarily in Luxembourg, Switzerland, Singapore and the U.S. The Company believes it is necessary to maintain a full valuation allowance against the deferred tax assets related to tax losses carried forward in Switzerland, Singapore and the U.S. after review of all available positive and negative evidence, including uncertainty regarding the ability of the concerned operations to generate future taxable income to utilize the losses carried forward and realize the deferred tax assets. The weighting of the positive and negative evidence is commensurate with the extent to which they can be objectively verified. As mentioned above, a partial release of $18,351 of the valuation allowance previously held against a deferred tax asset related to tax losses carried forward in Luxembourg was recorded as of December 31, 2016 . The Company believes, after review of all positive and negative evidence, it is now more-likely-than-not to have sufficient future taxable income to realize a portion of that deferred tax asset. The Company will continue to monitor all available positive and negative evidence, including its expectations for future taxable income in the relevant jurisdictions, in relation to the recoverability of its existing deferred tax balances. If the Company’s positive evidence continues to develop favorably in the foreseeable future, it is possible that further releases of the valuation allowances related to deferred tax asset balances will occur. As at December 31, 2016 and 2015 , the Company had no accrued liabilities for tax, interest and penalties relating to uncertain tax positions. Interest and penalties related to uncertain tax positions would be recognized in income tax expense. The Company has undistributed earnings in several foreign subsidiaries. If such earnings were to be distributed, as dividends or otherwise, they may be subject to income and withholding taxes. As a general rule, the Company intends to only distribute earnings that can be distributed in a tax free manner and indefinitely reinvest any other earnings. Determination of the amount of unrecognized deferred tax liability related to these earnings is currently not practicable due to the different possible methods for repatriating earnings. As at December 31, 2016 , the Company had no open examinations by local tax authorities. The Company has open tax years that are potentially subject to examinations by local tax authorities in the following major tax jurisdictions: the U.K., 2015 and 2016; the U.S., 2013 to 2016; Switzerland, 2012 to 2016; and Canada, 2012 to 2016.

Accumulated other comprehensive

Accumulated other comprehensive loss	12 Months Ended
	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Abstract]
Accumulated other comprehensive loss	Accumulated other comprehensive (loss) gain The changes in accumulated other comprehensive (loss) gain, by component for the years ended December 31, 2016 , 2015 and 2014 are as follows: Year Ended December 31, 2016 Foreign currency translation adjustment Minimum pension liability Cash flow hedge Total Balance, net of tax, beginning of year $ (11,834 ) $ 334 $ (1,069 ) $ (12,569 ) Other comprehensive (loss) gain, net of tax (10,440 ) (484 ) 277 (10,647 ) Balance, net of tax, end of year $ (22,274 ) $ (150 ) $ (792 ) $ (23,216 ) Year Ended December 31, 2015 Foreign currency translation adjustment Minimum pension liability Cash flow hedge Total Balance, net of tax, beginning of year $ (8,118 ) $ (210 ) $ (228 ) $ (8,556 ) Other comprehensive (loss) gain, net of tax (3,716 ) 544 (841 ) (4,013 ) Balance, net of tax, end of year $ (11,834 ) $ 334 $ (1,069 ) $ (12,569 ) Year Ended December 31, 2014 Foreign currency translation adjustment Minimum pension liability Cash flow hedge Total Balance, net of tax, beginning of year $ (617 ) $ — $ — $ (617 ) Other comprehensive loss, net of tax (7,501 ) (210 ) (228 ) (7,939 ) Balance, net of tax, end of year $ (8,118 ) $ (210 ) $ (228 ) $ (8,556 )

Commitments and contingencies

Commitments and contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	Commitments and contingencies (a) Concentrations of credit risk The Company underwrites a significant amount of its reinsurance business through three particular brokers as set out below. There is credit risk associated with payments of insurance and reinsurance balances to the Company if these brokers are unable to fulfill their contractual obligations. These companies are large, well established, and there are no indications they are financially distressed. There was no other broker or party insured or reinsured that accounted for more than 10% of gross premiums written for the periods mentioned. The following table shows the percentage of gross premiums written by broker for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Marsh & McLennan Companies, Inc. 28.8 % 28.2 % 28.5 % Aon Benfield Group Ltd. 16.2 % 15.5 % 20.0 % Willis Towers Watson plc 14.1 % 14.3 % 18.0 % (b) Employment agreements The Company has entered into employment agreements with certain individuals that provide for executive benefits and severance payments under certain circumstances. (c) Operating leases The Company leases office space and office equipment under operating leases. Total rent expense with respect to these operating leases for the year ended December 31, 2016 was approximately $9,761 ( 2015 : $10,143 , 2014 : $10,540 ). Future minimum lease commitments are as follows: December 31, 2016 2017 $ 11,878 2018 12,214 2019 11,958 2020 11,059 2021 10,316 2022 and thereafter 46,418 Total $ 103,843 (d) Funds at Lloyd’s Talbot operates in Lloyd’s through a corporate member, Talbot 2002 Underwriting Capital Ltd (“T02”), which is the sole participant in Syndicate 1183. Lloyd’s sets T02’s required capital annually based on Syndicate 1183’s business plan, rating environment and reserving environment together with input arising from Lloyd’s discussions with, inter alia, regulatory and rating agencies. Such capital, called Funds at Lloyd’s (“FAL”), comprises cash and investments. The Company provided FAL in the amount of $583,600 for the 2017 underwriting year ( 2016 : $617,000 ). The amounts which are provided as FAL are not available for distribution to the Company for the payment of dividends. Talbot’s corporate member may also be required to maintain funds under the control of Lloyd’s in excess of its capital requirement and such funds also may not be available for distribution to the Company for the payment of dividends. (e) Lloyd’s Central Fund Whenever a member of Lloyd’s is unable to pay its debts to policyholders, such debts may be payable by the Lloyd’s Central Fund. If Lloyd’s determines that the Central Fund needs to be increased, it has the power to assess premium levies on current Lloyd’s members up to 3% of a member’s underwriting capacity in any one year. The Company does not believe that any assessment is likely in the foreseeable future and has not provided any allowance for such an assessment. However, based on the Company’s 2017 estimated premium income at Lloyd’s of £600,000 , at December 31, 2016 exchange rate of £1 equals $1.23 and assuming the maximum 3% assessment, the Company would be assessed approximately $22,140 . (f) Investment affiliate commitments As discussed in Note 7, “Investments,” on December 20, 2011 the Company entered into an Assignment and Assumption Agreement with Aquiline Capital Partners LLC, pursuant to which it assumed total capital commitments of $50,000 . The Company’s remaining commitment at December 31, 2016 was $1,700 ( December 31, 2015 : $3,413 ). On October 2, 2014, the Company assumed an additional investment in Aquiline Capital Partners II GP (Offshore) Ltd. as part of the Western World acquisition representing a total capital commitment of $10,000 . The Company’s remaining capital commitment at December 31, 2016 was $340 ( December 31, 2015 : $683 ). On November 7, 2014, the Company entered into a Subscription Agreement with Aquiline Capital Partners III GP (Offshore) Ltd., pursuant to which it assumed total capital commitments of $100,000 in respect of Limited Partnership Interests in Aquiline Financial Services Fund III L.P. (the “Fund”). The Company’s remaining commitment at December 31, 2016 was $62,031 ( December 31, 2015 : $86,110 ). (g) AlphaCat commitments On December 29, 2014, the Company entered into an agreement with an AlphaCat ILS fund pursuant to which it assumed total capital commitments of $20,000 . On December 29, 2015, the Company assumed an additional capital commitment of $20,000 . The Company’s remaining unfunded capital commitment at December 31, 2016 was $nil ( December 31, 2015 : $10,000 ). On December 30, 2015, the Company entered into an agreement with another AlphaCat ILS fund pursuant to which it assumed total capital commitments of $25,000 . The Company’s remaining unfunded capital commitment at December 31, 2016 was $nil ( December 31, 2015 : $9,536 ). On December 30, 2016, a portion of the Company’s initial investment was returned and the Company assumed an additional capital commitment of $25,000 . The Company’s remaining unfunded capital commitment on the additional investment at December 31, 2016 was $10,000 . (h) Fixed maturity commitments At December 31, 2016 , the Company had an outstanding commitment to participate in certain secured loan facilities through participation agreements with an established loan originator. The undrawn amount under the revolver facility participations as at December 31, 2016 was $28,499 ( December 31, 2015 : $34,888 ). (i) Other investment commitments At December 31, 2016 , the Company had capital commitments in certain other investments of $308,000 ( December 31, 2015 : $263,000 ). The Company’s remaining unfunded capital commitment to these investments at December 31, 2016 was $156,134 ( December 31, 2015 : $185,548 ). (j) Structured settlements As at December 31, 2016 , the Company is contingently liable for the present value of amounts not yet due under annuities purchased by Western World where the claimant is the payee for the amount of $3,186 ( December 31, 2015 : $3,108 ).

Related party transactions

Related party transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related party transactions	Related party transactions The transactions listed below are classified as related party transactions as principals and/or directors of each counterparty are members of the Company’s board of directors. (a) Aquiline Capital Partners LLC (“Aquiline Capital”) Group Ark Insurance Pursuant to reinsurance agreements with a subsidiary of Group Ark Insurance Holdings Ltd. (“Group Ark”), the Company recognized gross premiums written during the year ended December 31, 2016 of $3,157 ( 2015 : $2,718 ; 2014 : $2,073 ) with $292 included in premiums receivable at December 31, 2016 ( December 31, 2015 : $82 ). The Company also recognized reinsurance premiums ceded during the year ended December 31, 2016 of $40 ( 2015 : $24 ; 2014 : $126 ) and had reinsurance balances payable of $ nil at December 31, 2016 ( December 31, 2015 : $4 ). The Company recorded $798 of loss reserves recoverable at December 31, 2016 ( December 31, 2015 : $790 ) and earned premium adjustments of $3,115 were recorded during the year ended December 31, 2016 ( 2015 : $2,833 ; 2014 : $1,982 ). Until July 2016, Aquiline Capital were shareholders of Group Ark. Christopher E. Watson, a director of the Company and senior principal of Aquiline Capital, serves as a director of Group Ark. Wellington Pursuant to reinsurance agreements with a subsidiary of Wellington Insurance Company (“Wellington”), the Company recognized gross premiums written during the year ended December 31, 2016 of $2,860 ( 2015 and 2014 : $ nil ) with $666 included in premiums receivable at December 31, 2016 ( December 31, 2015 : $ nil ). The Company also recognized earned premium adjustments during the year ended December 31, 2016 of $2,603 ( 2015 and 2014 : $ nil ). Aquiline Capital are shareholders of Wellington and Christopher E. Watson, a director of the Company and senior principal of Aquiline Capital, serves as a director of Wellington. Conning On November 24, 2009, the Company entered into an Investment Management Agreement with Conning, Inc. (“Conning”) to manage a portion of the Company’s investment portfolio. Aquiline Capital acquired Conning on June 16, 2009. Jeffrey W. Greenberg, a director of the Company, serves as a director of Conning Holdings Corp., the parent company of Conning. During the third quarter of 2015, Aquiline Capital disposed of its investment in Conning resulting in it no longer being a related party with effect from September 30, 2015. Investment management fees earned by Conning for the years ended December 31, 2015 and 2014 were $841 and $1,125 , respectively. Aquiline II On December 20, 2011, the Company entered into an Agreement with Aquiline Capital and Aquiline II General Partner pursuant to which the Company has assumed 100% of Aquiline Capital’s interest in the Aquiline II Partnership representing a total capital commitment of $50,000 (the “Aquiline II Commitment”), as a limited partner in the Partnership (the “Transferred Interest”). On October 2, 2014, the Company assumed an additional investment in the Aquiline II Partnership as part of the Western World acquisition representing a total capital commitment of $10,000 . Messrs. Greenberg and Watson, directors of the Company, serve as managing principal and senior principal, respectively, of Aquiline Capital. For the year ended December 31, 2016 , the Company incurred partnership fees of $843 ( 2015 : $1,519 ; 2014 : $410 ) and, for the years ended December 31, 2016 , 2015 and 2014 , had net capital (distributions) contributions of ($9,032) , $6,093 and $12,468 , respectively. Aquiline III On November 7, 2014, the Company entered into a Subscription Agreement with the Aquiline III General Partner pursuant to which the Company committed and agreed to purchase limited partnership or other comparable limited liability equity interests (the “Limited Partnership Interests”) in the “Aquiline III Partnership, and/or one or more Alternative Investment Vehicles and Intermediate Entities (together with the Aquiline III Partnership, the “Fund” or the “Entities”) with a capital commitment (the “Aquiline III Commitment”) in an amount equal to $100,000 , as a limited partner in the Aquiline III Partnership. For the year ended December 31, 2016 , the Company incurred partnership fees of $2,031 ( 2015 : $1,814 ; 2014 : $ nil ) and, for the years ended December 31, 2016 , 2015 and 2014 , made net capital contributions of $23,873 and $13,793 and $nil, respectively. (b) Other Certain shareholders of the Company and their affiliates, as well as employees of entities associated with directors and officers may have purchased insurance and/or reinsurance from the Company in the ordinary course of business. The Company does not believe these transactions to be material.

Earnings per share

Earnings per share	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Earnings per share	Earnings per share The following table sets forth the computation of basic earnings per share and earnings per diluted share available to common shareholders for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Basic earnings per share Net income available to Validus common shareholders $ 359,384 $ 374,893 $ 479,963 Less: Dividends on outstanding warrants — (3,566 ) (6,208 ) Net income allocated to Validus common shareholders $ 359,384 $ 371,327 $ 473,755 Weighted average number of common shares outstanding 81,041,974 83,107,236 90,354,745 Basic earnings per share available to Validus common shareholders $ 4.43 $ 4.47 $ 5.24 Earnings per diluted share Net income available to Validus common shareholders $ 359,384 $ 374,893 $ 479,963 Less: Dividends on outstanding warrants — — — Net income allocated to Validus common shareholders $ 359,384 $ 374,893 $ 479,963 Weighted average number of common shares outstanding 81,041,974 83,107,236 90,354,745 Share equivalents: Warrants — 2,090,248 2,789,032 Stock options 28,196 151,867 745,561 Unvested restricted shares 1,289,290 1,077,409 800,933 Weighted average number of diluted common shares outstanding 82,359,460 86,426,760 94,690,271 Earnings per diluted share available to Validus common shareholders $ 4.36 $ 4.34 $ 5.07 Share equivalents that would result in the issuance of common shares of 133,810 , 167,417 and 199,740 were outstanding for the years ended December 31, 2016 , 2015 and 2014 , respectively but were not included in the computation of earnings per diluted share because the effect would be antidilutive.

Segment information

Segment information	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segment information	Segment information The Company conducts its operations worldwide through four operating segments, which have been determined under ASC Topic 280 “Segment Reporting” to be Validus Re, Talbot, Western World and AlphaCat. The Company’s operating segments are strategic business units that offer different products and services. They are managed and have capital allocated separately because each segment undertakes different strategies. A description of each of the Company’s operating segments and its corporate and investments function is as follows: Validus Re Segment The Validus Re segment is focused primarily on treaty reinsurance. The primary lines in which the segment conducts business are property, marine and specialty which includes agriculture, aerospace and aviation, financial lines of business, nuclear, terrorism, life, accident & health, workers’ compensation, crisis management, contingency, technical lines, composite, trade credit and casualty. Talbot Segment The Talbot segment is focused on a wide range of marine and energy, political lines, commercial property, financial lines, contingency, accident & health and aviation classes of business on an insurance or facultative reinsurance basis and principally property, aerospace and marine classes of business on a treaty reinsurance basis. Western World Segment The Western World segment is focused on providing commercial insurance products on a surplus lines and specialty admitted basis. Western World specializes in underwriting classes of business that are not easily placed in the standard insurance market due to their complexity, high hazard, or unusual nature; including general liability, property and professional liability classes of business. AlphaCat Segment The AlphaCat segment leverages the Company’s underwriting and analytical expertise and earns management and performance fees from the Company and other third party investors primarily through the AlphaCat ILS funds and sidecars. Corporate and Investments The Company has a corporate and investments function (“Corporate and Investments”), which includes the activities of the parent company, and which carries out certain functions for the group, including investment management. Corporate and Investments includes investment income on a managed basis and other non-segment expenses, predominantly general and administrative, stock compensation and finance expenses. Corporate and Investments also denotes the activities of certain key executives such as the Chief Executive Officer and Chief Financial Officer. For internal reporting purposes, Corporate and Investments is reflected separately; however, it is not considered an operating segment under these circumstances. Other reconciling items include, but are not limited to, the elimination of certain inter segment revenues and expenses and other items that are not allocated to the operating segments. Underwriting income and the AlphaCat asset manager view are non-GAAP financial measures. A reconciliation of segmental income to net income available to Validus is included in the tables below. The following tables summarize the results of our operating segments and “Corporate and Investments”: Years Ended December 31, Validus Re Segment Information 2016 2015 2014 Underwriting revenues Gross premiums written $ 1,111,054 $ 1,126,759 $ 1,118,532 Reinsurance premiums ceded (111,564 ) (149,088 ) (163,678 ) Net premiums written 999,490 977,671 954,854 Change in unearned premiums (55,545 ) 12,542 (37,570 ) Net premiums earned 943,945 990,213 917,284 Other insurance related (loss) income (55 ) 3,575 3,159 Total underwriting revenues 943,890 993,788 920,443 Underwriting deductions Losses and loss expenses 411,488 457,976 307,290 Policy acquisition costs 181,040 166,387 141,670 General and administrative expenses 72,770 78,428 74,739 Share compensation expenses 11,034 10,350 9,739 Total underwriting deductions 676,332 713,141 533,438 Underwriting income $ 267,558 $ 280,647 $ 387,005 Selected ratios: Ratio of net to gross premiums written 90.0 % 86.8 % 85.4 % Losses and loss expense ratio 43.6 % 46.2 % 33.5 % Policy acquisition cost ratio 19.2 % 16.8 % 15.5 % General and administrative expense ratio (a) 8.8 % 9.0 % 9.2 % Expense ratio 28.0 % 25.8 % 24.7 % Combined ratio 71.6 % 72.0 % 58.2 % (a) The general and administrative expense ratio includes share compensation expenses. Years Ended December 31, Talbot Segment Information 2016 2015 2014 Underwriting revenues Gross premiums written $ 970,702 $ 1,018,835 $ 1,101,770 Reinsurance premiums ceded (175,729 ) (198,896 ) (192,211 ) Net premiums written 794,973 819,939 909,559 Change in unearned premiums (13,057 ) 18,152 (29,785 ) Net premiums earned 781,916 838,091 879,774 Other insurance related income 455 851 1,095 Total underwriting revenues 782,371 838,942 880,869 Underwriting deductions Losses and loss expenses 424,946 347,322 423,394 Policy acquisition costs 177,127 187,535 187,162 General and administrative expenses 134,479 155,306 150,828 Share compensation expenses 13,078 12,373 11,346 Total underwriting deductions 749,630 702,536 772,730 Underwriting income $ 32,741 $ 136,406 $ 108,139 Selected ratios: Ratio of net to gross premiums written 81.9 % 80.5 % 82.6 % Losses and loss expense ratio 54.3 % 41.4 % 48.1 % Policy acquisition cost ratio 22.7 % 22.4 % 21.3 % General and administrative expense ratio (a) 18.9 % 20.0 % 18.4 % Expense ratio 41.6 % 42.4 % 39.7 % Combined ratio 95.9 % 83.8 % 87.8 % (a) The general and administrative expense ratio includes share compensation expenses. Years Ended December 31, Western World Segment Information 2016 2015 2014 (a) Underwriting revenues Gross premiums written $ 323,220 $ 278,504 $ 65,235 Reinsurance premiums ceded (22,634 ) (18,877 ) (6,428 ) Net premiums written 300,586 259,627 58,807 Change in unearned premiums (27,354 ) (977 ) 14,189 Net premiums earned 273,232 258,650 72,996 Other insurance related income 912 1,044 264 Total underwriting revenues 274,144 259,694 73,260 Underwriting deductions Losses and loss expenses 183,812 171,878 51,035 Policy acquisition costs 64,442 41,408 3,169 General and administrative expenses 43,280 38,715 11,121 Share compensation expenses 2,543 2,083 135 Total underwriting deductions 294,077 254,084 65,460 Underwriting (loss) income $ (19,933 ) $ 5,610 $ 7,800 Selected ratios: Ratio of net to gross premiums written 93.0 % 93.2 % 90.1 % Losses and loss expense ratio 67.3 % 66.4 % 69.9 % Policy acquisition cost ratio 23.5 % 16.0 % 4.4 % General and administrative expense ratio (b) 16.8 % 15.8 % 15.4 % Expense ratio 40.3 % 31.8 % 19.8 % Combined ratio 107.6 % 98.2 % 89.7 % (a) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition. (b) The general and administrative expense ratio includes share compensation expenses. Years Ended December 31, AlphaCat Segment Information (a) 2016 2015 2014 Revenues Third party $ 18,771 $ 19,661 $ 18,667 Related party 3,329 5,309 7,467 Total revenues 22,100 24,970 26,134 Expenses General and administrative expenses 10,233 12,115 10,134 Share compensation expenses 249 580 501 Finance expenses 947 9,312 3,417 Tax expenses 90 — — Foreign exchange losses (gains) 19 (16 ) (20 ) Total expenses 11,538 21,991 14,032 Income before investment income from AlphaCat Funds and Sidecars 10,562 2,979 12,102 Investment income (loss) from AlphaCat Funds and Sidecars (b) AlphaCat Re & Master Fund — — (1,377 ) AlphaCat Sidecars 607 5,504 10,525 AlphaCat ILS Funds - Lower Risk 8,901 7,491 7,974 AlphaCat ILS Funds - Higher Risk 7,471 8,428 8,754 BetaCat ILS Funds 3,623 1,702 (51 ) PaCRe (23 ) (3,949 ) (4,340 ) Total investment income from AlphaCat Funds and Sidecars 20,579 19,176 21,485 Validus’ share of AlphaCat income $ 31,141 $ 22,155 $ 33,587 Supplemental information: Gross premiums written AlphaCat Sidecars $ (341 ) $ 45,755 $ 50,023 AlphaCat ILS Funds - Lower Risk 112,222 91,363 52,264 AlphaCat ILS Funds - Higher Risk 140,022 34,228 24,498 AlphaCat Direct (c) 18,499 4,780 — Total gross premiums written $ 270,402 $ 176,126 $ 126,785 (a) The results of AlphaCat are presented on an asset manager basis, which is non-GAAP. A reconciliation of Validus’ share of AlphaCat segment income to segmental income is presented in the tables below. (b) The investment income from the AlphaCat funds and sidecars is based on equity accounting. (c) AlphaCat Direct includes direct investments from third party investors in AlphaCat Re. Years Ended December 31, Corporate and Investments 2016 2015 2014 Investment income Managed net investment income (a) $ 141,718 $ 121,166 $ 95,800 Operating expenses General and administrative expenses 72,249 75,724 80,210 Share compensation expenses 16,003 12,955 11,352 Finance expenses (a) 57,183 61,071 60,309 Dividends on preferred shares 4,455 — — Tax (benefit) expense (a) (19,819 ) 6,376 155 Total operating expenses 130,071 156,126 152,026 Other items Net realized gains on managed investments (a) 14,680 1,698 12,160 Change in net unrealized gains (losses) on managed investments (a) 14,106 (32,007 ) (1,030 ) (Loss) income from investment affiliates (2,083 ) 4,281 8,411 Foreign exchange gains (losses) (a) 10,778 (8,172 ) (10,700 ) Other loss (766 ) (1,002 ) (2,243 ) Transaction expenses (b) — — (8,096 ) Total other items 36,715 (35,202 ) (1,498 ) Total Corporate and Investments $ 48,362 $ (70,162 ) $ (57,724 ) (a) These items exclude the components which are included in Validus’ share of AlphaCat and amounts which are consolidated from VIEs. (b) The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services. The following tables reconcile the results of our operating segments and “Corporate & Investments” to the Consolidated results of the Company for the years indicated: Year Ended December 31, 2016 Validus Re Segment Talbot Segment Western World Segment AlphaCat Segment and Consolidated VIEs Corporate and Investments Eliminations Total Underwriting revenues Gross premiums written $ 1,111,054 $ 970,702 $ 323,220 $ 270,402 $ — $ (26,673 ) $ 2,648,705 Reinsurance premiums ceded (111,564 ) (175,729 ) (22,634 ) (6,451 ) — 26,673 (289,705 ) Net premiums written 999,490 794,973 300,586 263,951 — — 2,359,000 Change in unearned premiums (55,545 ) (13,057 ) (27,354 ) (13,879 ) — — (109,835 ) Net premiums earned 943,945 781,916 273,232 250,072 — — 2,249,165 Other insurance related (loss) (55 ) 455 912 22,386 — (20,737 ) 2,961 Total underwriting revenues 943,890 782,371 274,144 272,458 — (20,737 ) 2,252,126 Underwriting deductions Losses and loss expenses 411,488 424,946 183,812 44,851 — — 1,065,097 Policy acquisition costs 181,040 177,127 64,442 26,905 — (32 ) 449,482 General and administrative expenses 72,770 134,479 43,280 34,333 72,249 (20,817 ) 336,294 Share compensation expenses 11,034 13,078 2,543 249 16,003 — 42,907 Total underwriting deductions 676,332 749,630 294,077 106,338 88,252 (20,849 ) 1,893,780 Underwriting income (loss) $ 267,558 $ 32,741 $ (19,933 ) $ 166,120 $ (88,252 ) $ 112 $ 358,346 Other items (a) — — — 2,478 (649 ) — 1,829 Dividends on preferred shares — — — — (4,455 ) — (4,455 ) Net investment income — — — 9,264 141,718 (597 ) 150,385 (Income) attributable to AlphaCat investors — — — (23,358 ) — — (23,358 ) Net (income) attributable to noncontrolling interests — — — (123,363 ) — — (123,363 ) Segmental income (loss) $ 267,558 $ 32,741 $ (19,933 ) $ 31,141 $ 48,362 $ (485 ) Net income available to Validus common shareholders $ 359,384 (a) Other items includes finance expenses, tax (benefit) expense, foreign exchange gains (losses), net realized and change in net unrealized gains (losses) on investments, income from investment and operating affiliates and other income (loss). Year Ended December 31, 2015 Validus Re Segment Talbot Segment Western World Segment AlphaCat Segment and Consolidated VIEs Corporate and Investments Eliminations Total Underwriting revenues Gross premiums written $ 1,126,759 $ 1,018,835 $ 278,504 $ 176,126 $ — $ (42,718 ) $ 2,557,506 Reinsurance premiums ceded (149,088 ) (198,896 ) (18,877 ) (4,538 ) — 42,718 (328,681 ) Net premiums written 977,671 819,939 259,627 171,588 — — 2,228,825 Change in unearned premiums 12,542 18,152 (977 ) (11,653 ) — — 18,064 Net premiums earned 990,213 838,091 258,650 159,935 — — 2,246,889 Other insurance related income 3,575 851 1,044 25,524 — (24,881 ) 6,113 Total underwriting revenues 993,788 838,942 259,694 185,459 — (24,881 ) 2,253,002 Underwriting deductions Losses and loss expenses 457,976 347,322 171,878 657 — — 977,833 Policy acquisition costs 166,387 187,535 41,408 16,327 — (1,599 ) 410,058 General and administrative expenses 78,428 155,306 38,715 39,055 75,724 (23,519 ) 363,709 Share compensation expenses 10,350 12,373 2,083 580 12,955 — 38,341 Total underwriting deductions 713,141 702,536 254,084 56,619 88,679 (25,118 ) 1,789,941 Underwriting income $ 280,647 $ 136,406 $ 5,610 $ 128,840 $ (88,679 ) $ 237 $ 463,061 Other items (a) — — — (17,967 ) (102,649 ) — (120,616 ) Dividends on preferred shares — — — — — — — Net investment income — — — 6,658 121,166 — 127,824 (Income) attributable to AlphaCat investors — — — (2,412 ) — — (2,412 ) Net (income) attributable to noncontrolling interests — — — (92,964 ) — — (92,964 ) Segmental income $ 280,647 $ 136,406 $ 5,610 $ 22,155 $ (70,162 ) $ 237 Net income available to Validus $ 374,893 (a) Other items includes finance expenses, tax expenses, foreign exchange gains (losses), net realized and change in net unrealized gains (losses) on investments, income from investment and operating affiliates and other income (loss). Year Ended December 31, 2014 Validus Re Segment Talbot Segment Western World Segment (c) AlphaCat Segment and Consolidated VIEs Corporate and Investments Eliminations Total Underwriting revenues Gross premiums written $ 1,118,532 $ 1,101,770 $ 65,235 $ 126,785 $ — $ (53,457 ) $ 2,358,865 Reinsurance premiums ceded (163,678 ) (192,211 ) (6,428 ) (4,348 ) — 53,457 (313,208 ) Net premiums written 954,854 909,559 58,807 122,437 — — 2,045,657 Change in unearned premiums (37,570 ) (29,785 ) 14,189 564 — — (52,602 ) Net premiums earned 917,284 879,774 72,996 123,001 — — 1,993,055 Other insurance related income 3,159 1,095 264 25,750 — (26,796 ) 3,472 Total underwriting revenues 920,443 880,869 73,260 148,751 — (26,796 ) 1,996,527 Underwriting deductions Losses and loss expenses 307,290 423,394 51,035 (16,704 ) — — 765,015 Policy acquisition costs 141,670 187,162 3,169 11,584 — (4,118 ) 339,467 General and administrative expenses 74,739 150,828 11,121 36,298 80,210 (23,834 ) 329,362 Share compensation expenses 9,739 11,346 135 501 11,352 — 33,073 Total underwriting deductions 533,438 772,730 65,460 31,679 91,562 (27,952 ) 1,466,917 Underwriting income $ 387,005 $ 108,139 $ 7,800 $ 117,072 $ (91,562 ) $ 1,156 $ 529,610 Other items (a) — — — (12,891 ) (53,866 ) — (66,757 ) Net investment income — — — 4,286 95,800 — 100,086 Net (income) attributable to noncontrolling interests — — — (74,880 ) — — (74,880 ) Transaction expenses (b) — — — — (8,096 ) — (8,096 ) Segmental income $ 387,005 $ 108,139 $ 7,800 $ 33,587 $ (57,724 ) $ 1,156 Net income available to Validus $ 479,963 (a) Other items includes finance expenses, tax expenses, foreign exchange gains (losses), net realized and change in net unrealized gains (losses) on investments, income from investment and operating affiliates and other income (loss). (b) The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services. (c) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition. The following table sets forth the gross premiums written by line of business for the years indicated: Years Ended December 31, 2016 2015 2014 (a) Property $ 1,128,523 $ 1,077,700 $ 1,050,109 Marine 363,656 471,857 576,478 Specialty 927,746 782,463 677,026 Liability 228,780 225,486 55,252 Total $ 2,648,705 $ 2,557,506 $ 2,358,865 (a) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition. The Company’s exposures are generally diversified across geographic zones. The following tables set forth the gross premiums written allocated to the territory of coverage exposure for the years indicated: Gross Premiums Written Year Ended December 31, 2016 Validus Re Talbot Western World AlphaCat Eliminations Total % United States $ 448,243 $ 103,415 $ 323,220 $ 64,766 $ (2,057 ) $ 937,587 35.4 % Worldwide excluding United States (a) 51,902 148,347 — 22,206 (689 ) 221,766 8.4 % Australia and New Zealand 7,389 10,844 — 4,949 (133 ) 23,049 0.9 % Europe 28,967 34,264 — 3,245 (695 ) 65,781 2.4 % Latin America and Caribbean 47,586 102,293 — — (9,484 ) 140,395 5.3 % Japan 40,099 6,580 — 3,221 (33 ) 49,867 1.9 % Canada 3,349 6,834 — 207 (147 ) 10,243 0.4 % Rest of the world (b) 22,595 107,106 — — (2,449 ) 127,252 4.8 % Sub-total, non United States 201,887 416,268 — 33,828 (13,630 ) 638,353 24.1 % Worldwide including United States (a) 167,065 98,311 — 170,253 (10,983 ) 424,646 16.0 % Other locations non-specific (c) 293,859 352,708 — 1,555 (3 ) 648,119 24.5 % Total $ 1,111,054 $ 970,702 $ 323,220 $ 270,402 $ (26,673 ) $ 2,648,705 100.0 % Gross Premiums Written Year Ended December 31, 2015 Validus Re Talbot Western World AlphaCat Eliminations Total % United States $ 530,541 $ 106,679 $ 278,504 $ 41,134 $ (2,547 ) $ 954,311 37.4 % Worldwide excluding United States (a) 52,860 127,540 — 8,107 (1,186 ) 187,321 7.3 % Australia and New Zealand 12,190 8,974 — 624 (244 ) 21,544 0.8 % Europe 48,240 38,657 — 2,504 (1,135 ) 88,266 3.5 % Latin America and Caribbean 46,258 103,318 — 38 (15,481 ) 134,133 5.2 % Japan 38,885 5,171 — 1,671 (109 ) 45,618 1.8 % Canada 3,129 6,666 — 458 (231 ) 10,022 0.4 % Rest of the world (b) 21,498 103,237 — — (3,660 ) 121,075 4.7 % Sub-total, non United States 223,060 393,563 — 13,402 (22,046 ) 607,979 23.7 % Worldwide including United States (a) 139,419 100,523 — 116,523 (18,120 ) 338,345 13.2 % Other locations non-specific (c) 233,739 418,070 — 5,067 (5 ) 656,871 25.7 % Total $ 1,126,759 $ 1,018,835 $ 278,504 $ 176,126 $ (42,718 ) $ 2,557,506 100.0 % Gross Premiums Written Year Ended December 31, 2014 Validus Re Talbot Western World (d) AlphaCat Eliminations Total % United States $ 437,124 $ 108,458 $ 65,235 $ 26,067 $ (3,664 ) $ 633,220 26.8 % Worldwide excluding United States (a) 76,370 139,570 — 6,727 (1,575 ) 221,092 9.4 % Australia and New Zealand 20,617 9,736 — 1,019 (360 ) 31,012 1.3 % Europe 57,223 45,615 — 2,305 (1,292 ) 103,851 4.4 % Latin America and Caribbean 56,102 116,281 — — (26,007 ) 146,376 6.2 % Japan 42,813 4,116 — 608 (111 ) 47,426 2.0 % Canada 3,793 10,194 — 214 (337 ) 13,864 0.6 % Rest of the world (b) 25,272 93,012 — — (3,805 ) 114,479 4.9 % Sub-total, non United States 282,190 418,524 — 10,873 (33,487 ) 678,100 28.8 % Worldwide including United States (a) 175,098 96,187 — 89,845 (16,196 ) 344,934 14.6 % Other locations non-specific (c) 224,120 478,601 — — (110 ) 702,611 29.8 % Total $ 1,118,532 $ 1,101,770 $ 65,235 $ 126,785 $ (53,457 ) $ 2,358,865 100.0 % (a) Represents risks in two or more geographic zones. (b) Represents risks in one geographic zone. (c) The other locations non-specific category refers to business for which an analysis of exposure by geographic zone is not applicable since these exposures can span multiple geographic areas and, in some instances, are not fixed locations. (d) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.

Statutory and regulatory requir

Statutory and regulatory requirements	12 Months Ended
	Dec. 31, 2016
Statutory and regulatory requirements [Abstract]
Statutory and regulatory requirements	Statutory and regulatory requirements Validus Holdings, Ltd. has operations which are subject to laws and regulations in the jurisdictions in which they operate, the most significant of which are Bermuda, the United Kingdom, the United States and Switzerland. As a holding company, Validus Holdings, Ltd.’s principal sources of income are dividends or other sources of permitted distributions from its subsidiaries. These funds provide the cash flow required for dividend payments to the Company’s shareholders. The holding company has no material restrictions on its ability to make distributions to shareholders however, the ability of our (re)insurance subsidiaries to make distributions is limited by the applicable local laws and relevant regulations of the various countries in which we operate. The Company’s subsidiaries are required to maintain certain measures of solvency and liquidity which provide restrictions on declaring dividends and distributions. The Company’s (re)insurance subsidiaries prepare their statutory financial statements in conformity with statutory accounting practices prescribed or permitted by the applicable local laws and relevant regulatory authority. The statutory financial statements may vary materially from statements prepared in accordance with U.S. GAAP. Statutory capital and surplus as at December 31, 2016 and 2015 and statutory net income for the years ended December 31, 2016 , 2015 and 2014 for our (re)insurance subsidiaries based in our most significant regulatory jurisdictions were as follows: Statutory Capital and Surplus Required Actual Statutory Net Income December 31, December 31, Years Ended December 31, 2016 2015 2016 2015 2016 2015 2014 Bermuda $ 734,045 $ 1,463,408 $ 3,712,369 $ 3,469,849 $ 369,684 $ 329,260 $ 511,652 United States 78,342 80,047 416,746 421,047 7,795 32,255 105,210 Switzerland 267,000 259,000 806,099 750,356 46,362 21,379 44,939 During the year ended December 31, 2016 , dividends and distributions to the Company from its subsidiaries, net of amounts reinvested in subsidiaries were $320,000 ( 2015 : $465,000 ). (a) Bermuda The Company has five Bermuda based insurance subsidiaries: Validus Reinsurance, Ltd., a Class 4 insurer; Validus Reinsurance (Switzerland) Ltd (Bermuda Branch), a Class 4 insurer; IPCRe Limited (“IPCRe”), a Class 3A insurer; AlphaCat Reinsurance Ltd., a Class 3 insurer; and Mont Fort Re Ltd., a Class 3 insurer. Each of these Bermuda insurance subsidiaries is registered under the Insurance Act. The Company also has two Bermuda based subsidiaries which are licensed as Special Purpose Insurers (“SPIs”) under the Insurance Act, AlphaCat Re 2011, Ltd. and AlphaCat Re 2012, Ltd. The Company’s Bermuda based insurance subsidiaries are required to maintain minimum statutory capital and surplus equal to the greater of a minimum solvency margin (“MSM”) and the Enhanced Capital Requirement (“ECR”) where applicable. The ECR is equal to the higher of the MSM or the Bermuda Solvency Capital Requirement (“BSCR”) model or approved internal capital model. The BSCR for the relevant insurers for the year ended December 31, 2016 will not be filed with the BMA until April 2017 . As a result, the required statutory capital and surplus as at December 31, 2016 , of $734,045 is based on the MSM of all relevant insurers, whereas the required statutory capital and surplus as at December 31, 2015 of $1,463,408 is based on the MSM and ECR where applicable for all relevant insurers. Actual statutory capital and surplus includes capital held in support of FAL which is not available for distribution to the Company. For further details refer to Note 23 , “Commitments and contingencies.” At December 31, 2016 and 2015 , the actual statutory capital and surplus of the Bermuda based insurance subsidiaries exceeded the relevant regulatory requirements. The ability of certain of these insurance subsidiaries to pay dividends to us is limited under Bermuda law and regulations. The Insurance Act provides that each of the Class 3A and 4 Bermuda subsidiaries may not declare or pay, in any financial year, dividends of more than 25% of its total statutory capital and surplus (as shown on its statutory balance sheet in relation to the previous financial year) unless it files with the BMA at least seven days prior to the payment, an affidavit signed by at least two directors and such insurance subsidiary’s principal representative, stating that in their opinion such subsidiary will continue to satisfy the required margins following declaration of those dividends, however, there is no additional requirement for BMA approval. In addition, before reducing its total statutory capital by 15% or more (as set out in its previous year’s statutory financial statements) each of the Class 3A and Class 4 Bermuda insurance subsidiaries must make application to the BMA for permission to do so; such application shall consist of an affidavit signed by at least two directors and such insurance subsidiary’s principal representative stating that in their opinion the proposed reduction in capital will not cause such subsidiaries to fail to meet its relevant margins, and such other information as the BMA may require. The Insurance Act permits each of the Class 3 insurers to declare or pay any dividends during any financial year so long as it does not cause the insurance subsidiary to fail to meet its relevant margins subject to the restrictions set out herein and other than in respect of IPCRe. Class 3 insurers, before reducing by 15% or more of its total statutory capital, as set out in its previous year’s financial statements, are required to apply to the BMA for its approval and provide such information as the BMA may require. As at December 31, 2016 , the Company’s Bermuda insurance subsidiaries have the ability to distribute up to $1,335,300 of unrestricted net assets as dividend payments or return of capital to Validus Holdings, Ltd. (December 31, 2015 : $1,008,367 ) without prior regulatory approval. The Company’s primary restrictions on net assets of insurance subsidiaries consist of regulatory requirements placed upon the regulated insurance subsidiaries to hold minimum amounts of total statutory capital and surplus and other than the restriction on IPCRe noted above, there were no other material restrictions on net assets in place as of December 31, 2016 . The Company’s principal operating subsidiary in Bermuda, Validus Reinsurance, Ltd., maintains a branch office in Singapore. As the branch office is not considered a separate entity for regulatory purposes, the required and actual statutory capital and surplus amount includes amounts, as set out above, related to the applicable branch office. The branch office is subject to additional minimum capital or asset requirements in its country of domicile. At December 31, 2016 and 2015 , the actual capital and assets for the branch exceeded the relevant local regulatory requirements. (b) United Kingdom - Lloyd’s As disclosed in Note 23 (d), “ Commitments and contingencies, ” Syndicate 1183 and T02 are subject to regulation by the Council of Lloyd’s. Syndicate 1183 and T02 are also subject to regulation by the U.K. Financial Conduct Authority (“FCA”) and Prudential Regulation Authority (“PRA”) under the Financial Services and Market Act 2000. T02 is a corporate member of Lloyd’s. As a corporate member of Lloyd’s, T02 is bound by the rules of the Society of Lloyd’s, which are prescribed by Bye-laws and Requirements made by the Council of Lloyd’s under powers conferred by the Lloyd’s Act 1982. These rules (among other matters) prescribe T02’s membership subscription, the level of its contribution to the Lloyd’s central fund and the assets it must deposit with Lloyd’s in support of its underwriting. The Council of Lloyd’s has broad power to sanction breaches of its rules, including the power to restrict or prohibit a member’s participation on Lloyd’s syndicates. The capital required to support a Syndicate’s underwriting capacity, or FAL, is assessed annually and is determined by Lloyd’s in accordance with the rules of the Society of Lloyd’s. The capital to support the underwriting of Syndicate 1183 is provided by the Company’s Bermuda based insurance subsidiaries in the form of cash and investments held at Lloyd’s. The amount provided as FAL is not available for distribution to the Company for the payment of dividends. Each year, during the second quarter, the corporate member applies to Lloyd’s to release accumulated funds, whether syndicate profits, interest on FAL or other which are in excess of the agreed FAL amount. At December 31, 2016 and 2015 , the actual capital and assets exceeded the relevant local regulatory requirements. The release for the year ended December 31, 2015 enabled a dividend payment to the Company of $30,000 during the year ended December 31, 2016 ( 2015 : $65,000 ). (c) United States The Company has three U.S. based insurance subsidiaries domiciled in New Hampshire: Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company, which are required to file financial statements prepared in accordance with statutory accounting practices prescribed or permitted by the New Hampshire State Insurance Department (“NHSID”). State insurance laws and regulations prescribe accounting practices for determining statutory net income and equity for insurance companies. In addition, state regulators may permit statutory accounting practices that differ from such prescribed practices. The Company’s U.S. based insurance company subsidiaries did not use such permitted practices. The Company’s U.S. based insurance company subsidiaries are subject to certain Risk-Based Capital (“RBC”) requirements as specified by the National Association of Insurance Commissioners. Under those requirements, the minimum amount of capital and surplus required to be maintained by a property/casualty insurance company is based on various risk factors. At December 31, 2016 and 2015 , the Company’s U.S. based insurance company subsidiaries met the RBC requirements. New Hampshire insurance laws limit the amount of dividends Western World may pay to the Company in a 12-month period without the approval of the NHSID. These limitations are based on the lesser of: (i) a maximum of 10.0% of prior year end statutory surplus as determined under statutory accounting practices; or (ii) statutory net income, not including realized capital gains, for the 12-month period ending December 31, next preceding, but shall not include pro rata distributions of any class of the insurer’s own securities. In determining whether a dividend or distribution is extraordinary, an insurer may carry forward net income from the previous two calendar years that has not already been paid out as dividends. This carry-forward is computed by taking the net income from the second and third preceding calendar years, not including realized capital gains, less dividends paid in the second and immediate preceding calendar years. As at December 31, 2016 , the maximum dividend that may be paid to the Company by its U.S. based insurance subsidiaries without obtaining prior approval was $490 ( December 31, 2015 : $17,599 ). During the year ended December 31, 2016 , our U.S. based insurance subsidiaries paid dividends to the Company of $18,500 ( 2015 : $80,300 ). (d) Switzerland Validus Re Swiss is a société anonyme headquartered in Zurich, Switzerland. The conduct of reinsurance business by a company headquartered in Switzerland requires a license granted by the Swiss Financial Market Supervisory Authority (“FINMA”). Validus Re Swiss maintains a branch office in Bermuda, Validus Reinsurance (Switzerland) Ltd. (Bermuda Branch), a Class 4 insurer. Required statutory capital and surplus is based on the Target Capital requirements calculated under the Swiss Solvency Test (“SST”). Required and actual statutory capital and surplus includes Validus Reinsurance (Switzerland) Ltd. and its Bermuda branch. At December 31, 2016 and 2015 , the actual capital and assets exceeded the relevant local regulatory requirements. Validus Re Swiss is funded by equity in the form of paid in capital by shares and in share premium. Under Swiss corporate law as modified by insurance supervisory law, a non-life insurance company is obliged to contribute to statutory legal reserves a minimum of 20% of any annual profit up to 50% of statutory capital, being paid in share capital. Validus Re Swiss has been substantially funded by share premium. Share premium can be distributed to shareholders without being subject to withholding tax. However, the distribution of any special dividend to shareholders remains subject to the approval of FINMA which considers the maintenance of solvency and the interests of reinsureds and creditors. Validus Reinsurance (Switzerland) Ltd. (Bermuda Branch) is exempt from filing an Annual Statutory Financial Return and Annual Capital and Solvency Return but is subject to the minimum required statutory capital and surplus requirements for Class 4 insurers and the SST. At December 31, 2016 and 2015 , the branch was in compliance with all relevant regulatory requirements.

Subsequent events

Subsequent events	12 Months Ended
	Dec. 31, 2016
Subsequent Events [Abstract]
Subsequent events	Subsequent events Dividends On February 9, 2017 , the Company announced a quarterly cash dividend of $0.38 per common share, payable on March 31, 2017 to shareholders of record on March 15, 2017 and a cash dividend of $0.3671875 per depositary share on the outstanding Series A Preferred Shares, payable on March 15, 2017 to shareholders of record on March 1, 2017 . Acquisition of ADM Crop Risk Services On January 30, 2017, the Company, through its wholly-owned subsidiary Stratford Insurance Company, entered into a definitive agreement with Archer Daniels Midland Company (“ADM”) under which the Company will acquire all of the outstanding stock of ADM Crop Risk Services (“CRS”). CRS is a primary crop insurance general agent with 1,170 agents across 36 states within the U.S. The purchase price for CRS will be approximately $127,500 in cash, subject to certain working capital and balance sheet adjustments. Completion of the transaction is conditioned on, among other things, regulatory approvals and satisfaction of various customary closing conditions. The transaction is currently expected to close during the second quarter of 2017.

Condensed unaudited quarterly f

Condensed unaudited quarterly financial information	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Condensed unaudited quarterly financial information	Unaudited quarterly financial data Quarters Ended December 31, 2016 September 30, 2016 June 30, March 31, Unaudited Unaudited Unaudited Unaudited Revenues Gross premiums written $ 339,454 $ 372,418 $ 764,042 $ 1,172,791 Reinsurance premiums ceded (40,635 ) (45,006 ) (36,229 ) (167,835 ) Net premiums written 298,819 327,412 727,813 1,004,956 Change in unearned premiums 241,580 236,363 (154,090 ) (433,688 ) Net premiums earned 540,399 563,775 573,723 571,268 Net investment income 38,153 43,514 39,257 29,461 Net realized gains (losses) on investments 9,220 4,397 2,724 (584 ) Change in net unrealized (losses) gains on investments (67,460 ) 5,459 31,428 47,444 Income (loss) from investment affiliates 2,166 453 (589 ) (4,113 ) Other insurance related income (loss) and other income 568 (610 ) 824 1,413 Foreign exchange (losses) gains (901 ) (766 ) 6,286 6,245 Total revenues 522,145 616,222 653,653 651,134 Expenses Losses and loss expenses 275,126 258,394 307,130 224,447 Policy acquisition costs 120,889 113,434 107,966 107,193 General and administrative expenses 77,955 82,443 89,688 86,208 Share compensation expenses 10,442 10,501 10,727 11,237 Finance expenses 14,630 14,521 14,166 15,203 Total expenses 499,042 479,293 529,677 444,288 Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors 23,103 136,929 123,976 206,846 Tax benefit (expense) 21,147 (1,830 ) (1,706 ) 2,118 Loss from operating affiliate — — — (23 ) (Income) attributable to AlphaCat investors (7,080 ) (5,564 ) (6,114 ) (4,600 ) Net income $ 37,170 $ 129,535 $ 116,156 $ 204,341 Net (income) attributable to noncontrolling interests (27,200 ) (37,439 ) (21,193 ) (37,531 ) Net income available to Validus 9,970 92,096 94,963 166,810 Dividends on preferred shares (2,203 ) (2,252 ) — — Net income available to Validus common shareholders $ 7,767 $ 89,844 $ 94,963 $ 166,810 Earnings per share Basic earnings per share available to Validus common shareholders $ 0.10 $ 1.12 $ 1.16 $ 2.01 Earnings per diluted share available to Validus common shareholders $ 0.10 $ 1.11 $ 1.14 $ 1.98 Cash dividends declared per common share $ 0.35 $ 0.35 $ 0.35 $ 0.35 Quarters Ended December 31, 2015 September 30, 2015 June 30, March 31, Unaudited Unaudited Unaudited Unaudited Revenues Gross premiums written $ 309,605 $ 402,509 $ 726,168 $ 1,119,224 Reinsurance premiums ceded (33,128 ) (48,810 ) (55,418 ) (191,325 ) Net premiums written 276,477 353,699 670,750 927,899 Change in unearned premiums 266,823 201,312 (98,062 ) (352,009 ) Net premiums earned 543,300 555,011 572,688 575,890 Net investment income 31,612 31,572 33,611 31,029 Net realized (losses) gains on investments (2,928 ) (1,187 ) 2,244 4,169 Change in net unrealized (losses) gains on investments (34,862 ) 3,916 (34,676 ) 33,227 (Loss) income from investment affiliates (1,261 ) 2,482 284 2,776 Other insurance related income and other income 2,545 1,526 100 940 Foreign exchange gains (losses) 797 (2,592 ) (2,671 ) (4,265 ) Total revenues 539,203 590,728 571,580 643,766 Expenses Losses and loss expenses 214,748 256,010 266,146 240,929 Policy acquisition costs 102,285 105,039 104,323 98,411 General and administrative expenses 98,563 96,886 84,025 84,235 Share compensation expenses 10,062 9,983 9,242 9,054 Finance expenses 16,581 18,512 18,682 20,967 Total expenses 442,239 486,430 482,418 453,596 Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors 96,964 104,298 89,162 190,170 Tax benefit (expense) 756 (2,018 ) (2,549 ) (2,565 ) (Loss) income from operating affiliate (1,708 ) (7,963 ) 1,738 3,984 (Income) attributable to AlphaCat investors (974 ) (1,438 ) — — Net income $ 95,038 $ 92,879 $ 88,351 $ 191,589 Net (income) attributable to noncontrolling interests (25,996 ) (26,229 ) (22,561 ) (18,178 ) Net income available to Validus 69,042 66,650 65,790 173,411 Dividends on preferred shares — — — — Net income available to Validus common shareholders $ 69,042 $ 66,650 $ 65,790 $ 173,411 Earnings per share Basic earnings per share available to Validus common shareholders $ 0.84 $ 0.79 $ 0.77 $ 2.07 Earnings per diluted share available to Validus common shareholders $ 0.81 $ 0.78 $ 0.75 $ 1.98 Cash dividends declared per common share $ 0.32 $ 0.32 $ 0.32 $ 0.32

Schedule I - Summary of investm

Schedule I - Summary of investments	12 Months Ended
	Dec. 31, 2016
Summary of Investments, Other than Investments in Related Parties [Abstract]
Summary of Investments Other than Investments in Related Parties	SCHEDULE I VALIDUS HOLDINGS, LTD. SUMMARY OF INVESTMENTS OTHER THAN INVESTMENTS IN RELATED PARTIES At December 31, 2016 (Expressed in thousands of U.S. dollars) Amortized Fair Amount U.S. government and government agency $ 809,392 $ 804,126 $ 804,126 Non-U.S. government and government agency 245,651 240,791 240,791 U.S. states, municipalities and political subdivisions 271,742 271,830 271,830 Agency residential mortgage-backed securities 684,490 679,595 679,595 Non-agency residential mortgage-backed securities 15,858 15,477 15,477 U.S. corporate 1,540,036 1,534,508 1,534,508 Non-U.S. corporate 418,520 410,227 410,227 Bank loans 579,121 570,399 570,399 Catastrophe bonds 157,486 158,331 158,331 Asset-backed securities 528,563 526,814 526,814 Commercial mortgage-backed securities 333,740 330,932 330,932 Total fixed maturities 5,584,599 5,543,030 5,543,030 Total short-term investments 2,796,358 2,796,170 2,796,170 Total other investments 380,130 405,712 405,712 Total $ 8,761,087 $ 8,744,912 $ 8,744,912

Schedule II - Condensed financi

Schedule II - Condensed financial information of registrant	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Financial Information of Registrant	SCHEDULE II VALIDUS HOLDINGS, LTD. CONDENSED FINANCIAL INFORMATION OF REGISTRANT BALANCE SHEETS As at December 31, 2016 and 2015 (Expressed in thousands of U.S. dollars, except share and per share information) December 31, 2016 December 31, 2015 Assets Fixed maturities trading, at fair value $ 92,197 $ 28,403 Cash and cash equivalents 11,780 25,306 Investments in subsidiaries on an equity basis 4,383,800 4,198,809 Balances due from subsidiaries — 10,389 Accrued investment income 239 49 Other assets 1,143 813 Total assets $ 4,489,159 $ 4,263,769 Liabilities Accounts payable and accrued expenses $ 26,884 $ 29,633 Balances due to subsidiaries 28,622 — Senior notes payable 245,362 245,161 Debentures payable 350,000 350,000 Total liabilities $ 650,868 $ 624,794 Shareholders’ Equity Authorized 571,428,571 common and preferred shares, par value $0.175 per share: Preferred shares (Issued and Outstanding: 2016—6,000; 2015—nil) $ 150,000 $ — Common shares (Issued: 2016—161,279,976; 2015—160,570,772; Outstanding: 2016—79,132,252; 2015—82,900,617) 28,224 28,100 Treasury shares (2016—82,147,724; 2015—77,670,155) (14,376 ) (13,592 ) Additional paid-in capital 821,023 1,002,980 Accumulated other comprehensive loss (23,216 ) (12,569 ) Retained earnings 2,876,636 2,634,056 Total shareholders’ equity $ 3,838,291 $ 3,638,975 Total liabilities and shareholders’ equity $ 4,489,159 $ 4,263,769 VALIDUS HOLDINGS, LTD. CONDENSED FINANCIAL INFORMATION OF REGISTRANT (Continued) STATEMENTS OF INCOME AND COMPREHENSIVE INCOME For the years ended December 31, 2016 , 2015 and 2014 (Expressed in thousands of U.S. dollars) Years Ended December 31, 2016 2015 2014 Revenues Net investment income $ 1,195 $ 317 $ 14 Net realized gains on investments 8,020 — — Change in net unrealized losses on investments (276 ) (395 ) — Foreign exchange gains 1,932 715 648 Total revenues 10,871 637 662 Expenses General and administrative expenses 72,235 74,015 86,108 Share compensation expenses 6,832 7,261 6,424 Finance expenses 47,108 47,722 47,689 Total expenses 126,175 128,998 140,221 Loss before equity in net earnings of subsidiaries (115,304 ) (128,361 ) (139,559 ) Equity in net earnings of subsidiaries 479,143 503,254 619,522 Net income available to Validus 363,839 374,893 479,963 Dividends on preferred shares (4,455 ) — — Net income available to Validus common shareholders $ 359,384 $ 374,893 $ 479,963 Comprehensive income: Net income available to Validus $ 363,839 $ 374,893 $ 479,963 Other comprehensive (loss) income: Change in foreign currency translation adjustments (10,440 ) (3,716 ) (7,501 ) Change in minimum pension liability, net of tax (484 ) 544 (210 ) Change in fair value of cash flow hedge 277 (841 ) (228 ) Other comprehensive loss (10,647 ) (4,013 ) (7,939 ) Comprehensive income available to Validus $ 353,192 $ 370,880 $ 472,024 VALIDUS HOLDINGS, LTD. CONDENSED FINANCIAL INFORMATION OF REGISTRANT (Continued) STATEMENTS OF CASH FLOWS For the years ended December 31, 2016 , 2015 and 2014 (Expressed in thousands of U.S. dollars) Years Ended December 31, 2016 2015 2014 Cash flows provided by (used in) operating activities Net income available to Validus $ 363,839 $ 374,893 $ 479,963 Adjustments to reconcile net income to net cash provided by (used in) operating activities: Equity in net earnings of subsidiaries (479,143 ) (503,254 ) (619,522 ) Dividends received from subsidiaries 30,000 620,700 100,000 Net realized gains on investments (8,020 ) — — Amortization of discount on senior notes 108 108 108 Share compensation expenses 6,832 7,261 6,424 Change in net unrealized losses on investments 276 395 — Amortization of premium on fixed maturity investments 115 105 — Change in: Other assets (238 ) 173 528 Accrued investment income (190 ) (49 ) — Balances due from subsidiaries 10,389 30,689 (12,030 ) Balances due to subsidiaries 28,622 — — Accounts payable and accrued expenses (4,348 ) 5,080 2,624 Net cash (used in) provided by operating activities (51,758 ) 536,101 (41,905 ) Cash flows provided by (used in) investing activities Purchases of fixed maturity investments (56,164 ) (28,903 ) — Investments in subsidiaries — (555,700 ) — Return of capital from subsidiaries 290,000 400,000 673,966 Net cash provided by (used in) investing activities 233,836 (184,603 ) 673,966 Cash flows provided by (used in) financing activities Issuance of preferred shares, net 144,852 — — Issuance of common shares, net (7,701 ) 17,407 5,347 Purchases of common shares under repurchase program (212,675 ) (260,430 ) (510,952 ) Dividends paid on preferred shares (4,455 ) — — Dividends paid on common shares (115,625 ) (112,967 ) (117,043 ) Net cash used in financing activities (195,604 ) (355,990 ) (622,648 ) Net (decrease) increase in cash (13,526 ) (4,492 ) 9,413 Cash and cash equivalents—beginning of year 25,306 29,798 20,385 Cash and cash equivalents—end of year $ 11,780 $ 25,306 $ 29,798

Schedule III - Supplementary in

Schedule III - Supplementary insurance information	12 Months Ended
	Dec. 31, 2016
Supplementary Insurance Information [Abstract]
Supplementary Insurance Information	SCHEDULE III VALIDUS HOLDINGS, LTD. SUPPLEMENTARY INSURANCE INFORMATION As at and for the years ended December 31, 2016 , 2015 and 2014 (Expressed in thousands of U.S. dollars) As at and for the year ended December 31, 2016 Deferred Acquisition Costs Reserve for Losses and Loss Expenses Unearned Premiums Net Premiums Earned Net Investment Income Losses and Loss Expenses Amortization of Deferred Acquisition Costs Other Operating Expenses Net Premiums Written Validus Re $ 79,588 $ 1,116,753 $ 352,646 $ 943,945 $ — $ 411,488 $ 181,040 $ 83,804 $ 999,490 Talbot 95,237 1,301,517 551,815 781,916 — 424,946 177,127 147,557 794,973 Western World 34,841 589,500 158,945 273,232 — 183,812 64,442 45,823 300,586 AlphaCat 4,060 48,534 38,961 250,072 — 44,851 26,905 34,582 263,951 Corporate & Investments and Eliminations (4,499 ) (61,109 ) (26,318 ) — 150,385 — (32 ) 67,435 — Total $ 209,227 $ 2,995,195 $ 1,076,049 $ 2,249,165 $ 150,385 $ 1,065,097 $ 449,482 $ 379,201 $ 2,359,000 As at and for the year ended December 31, 2015 Deferred Acquisition Costs Reserve for Losses and Loss Expenses Unearned Premiums Net Premiums Earned Net Investment Income Losses and Loss Expenses Amortization of Deferred Acquisition Costs Other Operating Expenses Net Premiums Written Validus Re $ 60,459 $ 1,146,869 $ 294,509 $ 990,213 $ — $ 457,976 $ 166,387 $ 88,778 $ 977,671 Talbot 92,095 1,302,635 533,558 838,091 — 347,322 187,535 167,679 819,939 Western World 28,622 600,331 130,101 258,650 — 171,878 41,408 40,798 259,627 AlphaCat 2,526 11,013 24,643 159,935 — 657 16,327 39,635 171,588 Corporate & Investments and Eliminations (2,700 ) (64,281 ) (16,601 ) — 127,824 — (1,599 ) 65,160 — Total $ 181,002 $ 2,996,567 $ 966,210 $ 2,246,889 $ 127,824 $ 977,833 $ 410,058 $ 402,050 $ 2,228,825 As at and for the year ended December 31, 2014 Deferred Acquisition Costs Reserve for Losses and Loss Expenses Unearned Premiums Net Premiums Earned Net Investment Income Losses and Loss Expenses Amortization of Deferred Acquisition Costs Other Operating Expenses Net Premiums Written Validus Re $ 59,091 $ 1,333,878 $ 305,138 $ 917,284 $ — $ 307,290 $ 141,670 $ 84,478 $ 954,854 Talbot 95,246 1,352,056 552,660 879,774 — 423,394 187,162 162,174 909,559 Western World 9,566 613,551 133,185 72,996 — 51,035 3,169 11,256 58,807 AlphaCat 1,281 15,278 13,060 123,001 — (16,704 ) 11,584 36,799 122,437 Corporate & Investments and Eliminations (4,162 ) (71,616 ) (14,814 ) — 100,086 — (4,118 ) 67,728 — Total $ 161,022 $ 3,243,147 $ 989,229 $ 1,993,055 $ 100,086 $ 765,015 $ 339,467 $ 362,435 $ 2,045,657

Schedule IV - Reinsurance

Schedule IV - Reinsurance	12 Months Ended
	Dec. 31, 2016
Supplemental Schedule of Reinsurance Premiums for Insurance Companies [Abstract]
Reinsurance	SCHEDULE IV VALIDUS HOLDINGS, LTD. REINSURANCE For the years ended December 31, 2016 , 2015 and 2014 (Expressed in thousands of U.S. dollars) Direct gross Ceded to Assumed Net amount Percentage Year Ended December 31, 2016 $ 853,885 $ 289,705 $ 1,794,820 $ 2,359,000 76 % Year Ended December 31, 2015 838,755 328,681 1,718,751 2,228,825 77 % Year Ended December 31, 2014 683,028 313,208 1,675,837 2,045,657 82 %

Schedule VI - Supplemental info

Schedule VI - Supplemental information for property-casualty underwriters	12 Months Ended
	Dec. 31, 2016
Supplemental Information for Property, Casualty Insurance Underwriters [Abstract]
Schedule of Supplemental Information Concerning Property/Casualty Insurance Operations	SCHEDULE VI VALIDUS HOLDINGS, LTD. SUPPLEMENTAL INFORMATION CONCERNING PROPERTY/CASUALTY INSURANCE OPERATIONS As at and for the years ended December 31, 2016 , 2015 and 2014 (Expressed in thousands of U.S. dollars) Affiliation with registrant Deferred acquisition costs Reserves for losses and loss expenses Reserves for unearned premiums Net earned premiums Net investment income Losses and loss expenses incurred related to Net paid losses and loss expenses Amortization of deferred acquisition costs Net premiums written Current year Prior year Consolidated Subsidiaries 2016 $ 209,227 $ 2,995,195 $ 1,076,049 $ 2,249,165 $ 150,385 $ 1,281,289 $ (216,192 ) $ 1,114,402 $ 449,482 $ 2,359,000 2015 181,002 2,996,567 966,210 2,246,889 127,824 1,283,970 (306,137 ) 1,167,839 410,058 2,228,825 2014 161,022 3,243,147 989,229 1,993,055 100,086 1,024,256 (259,241 ) 1,063,653 339,467 2,045,657

Significant accounting polici41

Significant accounting policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Basis of preparation	These Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The Company consolidates in these Consolidated Financial Statements the results of operations and financial position of all voting interest entities (“VOE”) in which the Company has a controlling financial interest and all variable interest entities (“VIE”) in which the Company is considered to be the primary beneficiary. The consolidation assessment, including the determination as to whether an entity qualifies as a VIE or VOE, depends on the facts and circumstances surrounding each entity. All significant intercompany accounts and transactions have been eliminated.
Use of estimates	The preparation of these financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. While management believes that the amounts included in the Consolidated Financial Statements reflect its best estimates and assumptions, actual results could differ from those estimates. The Company’s principal estimates include: • reserve for losses and loss expenses; • premium estimates for business written on a line slip or proportional basis; • the valuation of goodwill and intangible assets; • reinsurance recoverable balances including the provision for uncollectible amounts; and • investment valuation of financial assets. The term “ASC” used in these notes refers to Accounting Standard Codification issued by the United States Financial Accounting Standards Board (the “FASB”).
Premiums	Insurance premiums written are recorded in accordance with the terms of underlying policies. Reinsurance premiums written are recorded at the inception of the policy and are estimated based on information received from brokers, ceding companies and reinsureds, and any subsequent differences arising on such estimates will be recorded in the periods in which they are determined. Premiums written are earned on a pro-rated basis over the term of the policy. For contracts and policies written on a losses occurring basis, the risk period is generally the same as the contract or policy terms. For contracts written on a risks attaching basis, the risk period is based on the terms of the underlying contracts and policies and is generally assumed to be 24 months . The portion of the premiums written applicable to the unexpired terms of the underlying contracts and policies in force is recorded as unearned premiums. Reinstatement premiums are recorded at the time a loss event occurs and coverage limits for the remaining life of the contract are reinstated under predefined contract terms. The accrual of reinstatement premiums is based on our estimate of losses and loss expenses, which reflects management’s judgment, as described in Note 3 (c), “ Reserve for losses and loss expenses ” below.
Policy acquisition costs	Policy acquisition costs are costs that vary with, and are directly related to, the successful production of new and renewal business, and consist principally of commissions and brokerage expenses. Acquisition costs are shown net of commissions earned on reinsurance ceded. These costs are deferred and amortized over the periods in which the related premiums are earned. Deferred acquisition costs are limited to their estimated realizable value based on the related unearned premiums and anticipated claims expenses. The realizable value of the Company’s deferred acquisition costs is determined without consideration of investment income. Policy acquisition costs also include profit commissions. Profit commissions are recognized on a basis consistent with our estimate of losses and loss expenses.
Reserves for losses and loss expenses	The reserve for losses and loss expenses includes reserves for unpaid reported losses (“case reserves”) and for losses incurred but not reported (“IBNR”). Case reserves are established by management based on reports from brokers, ceding companies and insureds and represents the estimated ultimate cost of events or conditions that have been reported to, or specifically identified by, the Company. IBNR reserves are established by management based on actuarially determined estimates of ultimate losses and loss expenses. Inherent in the estimate of ultimate losses and loss expenses are expected trends in claim severity and frequency and other factors which may vary significantly as claims are settled. Accordingly, ultimate losses and loss expenses may differ materially from the amounts recorded in the Consolidated Financial Statements. These estimates are reviewed regularly and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments, if any, will be recorded in earnings in the period in which they become known. Prior period development arises from changes to these estimates recognized in the current year that relate to reserves for losses and loss expenses established in previous calendar years. Reserves for losses and loss expenses are based in part upon the estimation of case reserves from broker, insured and ceding company reported data. The Company also uses statistical and actuarial methods to estimate ultimate expected losses and loss expenses, from which IBNR losses can be calculated. The period of time from the occurrence of a loss to the reporting of a loss to the Company and to the settlement of the Company’s liability may be several months or years. During this period, additional facts and trends may be revealed. As these factors become apparent, reserves will be adjusted, sometimes requiring an increase or decrease in the overall reserves of the Company, and at other times requiring a reallocation of incurred but not reported reserves to specific case reserves. These estimates are reviewed and adjusted regularly, and such adjustments, if any, are reflected in earnings in the period in which they become known. While management believes that it has made a reasonable estimate of ultimate losses, there can be no assurances that ultimate losses and loss expenses will not exceed this estimate.
Reinsurance	In the normal course of business, the Company seeks to reduce the potential amount of loss arising from claims events by reinsuring certain levels of risk assumed in various areas of exposure with other insurers or reinsurers. The accounting for reinsurance ceded depends on the method of reinsurance. If the policy is on a “losses occurring” basis, reinsurance premiums ceded are expensed (and any commissions thereon are earned) on a pro-rata basis over the period the reinsurance coverage is provided. If the policy is a “risks attaching” policy, reinsurance premiums ceded are expensed (and any commissions thereon are earned) in line with the earning of the gross premiums to which the risk attaching policy relates. Prepaid reinsurance premiums represent the portion of premiums ceded applicable to the unexpired term of policies in force. Mandatory reinstatement premiums ceded are recorded at the time the loss event occurs. Reinsurance recoverables are based on contracts in force at the time of the underlying loss event. The method for determining the reinsurance recoverable on unpaid losses and loss expenses involves the actuarial estimates of unpaid losses and loss expenses as well as a determination of the Company’s ability to cede unpaid losses and loss expenses under its reinsurance treaties. The use of different assumptions could have a material effect on the provision for uncollectible reinsurance. To the extent the creditworthiness of the Company’s reinsurers was to deteriorate due to adverse events affecting the reinsurance industry, such as a large number of major catastrophes, actual uncollectible amounts could be significantly greater than the Company’s provision. Amounts recoverable from reinsurers are estimated in a manner consistent with the underlying liabilities.
Investments	The Company classifies its fixed maturity and short-term investments as trading and accounts for its other investments in accordance with ASC Topic 825 “Financial Instruments.” As such, all investments are carried at fair value with interest and dividend income and realized and unrealized gains and losses included in net income for the year. All investment transactions are recorded on a first-in-first-out basis and realized gains and losses on the sale of investments are determined on the basis of amortized cost (or cost). Interest on fixed maturity securities is recorded in net investment income when earned and includes amortization of premium or accretion of discount. For mortgage-backed securities, and any other holdings for which there is a prepayment risk, prepayment assumptions are evaluated and revised as necessary. Any adjustments required due to the resultant change in effective yields and maturities are recognized retrospectively. Prepayment fees or call premiums that are only payable to the Company when a security is called prior to its maturity, are earned when received and reflected in net investment income. Short-term investments primarily comprise of investments with a remaining maturity of less than one year at time of purchase and money market funds held at the Company’s investment managers. Certain short-term investments relate to funds held in trust in support of collateralized reinsurance transactions. Restricted cash primarily relates to funds held in trust for support of collateralized reinsurance transactions.
Other investments	The fair value of other investments is generally recorded on the basis of the net asset valuation criteria established by the managers of the investments, normally based upon the governing documents of such investments. In addition, due to a lag in reporting, some of the fund managers, fund administrators, or both, are unable to provide final fund valuations as of the Company’s reporting date. In these circumstances, the Company estimates the fair value of these funds by starting with the prior month’s or prior quarter’s fund valuation, adjusting these valuations for capital calls, redemptions or distributions and the impact of changes in foreign currency exchange rates, and then estimating the return for the current period. In circumstances in which the Company estimates the return for the current period, it uses all credible information available. This includes utilizing preliminary estimates reported by its fund managers, obtaining the valuation of underlying portfolio investments where such underlying investments are publicly traded and therefore have a readily observable price, using information that is available to the Company with respect to the underlying investments, reviewing various indices for similar investments or asset classes, as well as estimating returns based on the results of similar types of investments for which the Company has reported results, or other valuation methods, as necessary. Actual final fund valuations may differ, perhaps materially so, from the Company’s estimates and these differences are recorded in the period they become known as a change in estimate. Investments in which the Company has significant influence over the operating and financial policies of the investee are accounted for under the equity method of accounting. Under this method, the Company records its proportionate share of income or loss from such investments in its results for the period.
Fair value of financial instruments	Fair value is defined as the price received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date reflecting the highest and best use valuation concepts. ASC Topic 820 “ Fair Value Measurement and Disclosure ” provides a framework for measuring fair value by creating a hierarchy of fair value measurements that distinguishes market data between observable independent market inputs and unobservable market assumptions by the reporting entity. The guidance further expands disclosures about such fair value measurements. The guidance applies broadly to most existing accounting pronouncements that require or permit fair value measurements (including both financial and non-financial assets and liabilities) but does not require any new fair value measurements. The Company has adopted all authoritative guidance in effect as of the balance sheet date regarding certain market conditions that allow for fair value measurements that incorporate unobservable inputs where active market transaction based measurements are unavailable.
Derivative instruments	Fair Value Hedges The Company uses derivative instruments in the form of foreign currency forward exchange contracts to manage foreign currency risk. A foreign currency forward exchange contract involves an obligation to purchase or sell a specified amount of a specified currency at a future date at a price set at the time of the contract. Foreign currency forward exchange contracts will not eliminate fluctuations in the value of our assets and liabilities denominated in foreign currencies but rather allow the Company to establish a rate of exchange for a future point in time. The foreign currency forward exchange contracts are recorded as derivatives at fair value as either assets or liabilities, depending on their rights or obligations, with changes in fair value recorded as a net foreign exchange gain or loss in the Company’s Statements of Income and Comprehensive Income. To qualify for hedge accounting treatment, the derivative must be highly effective in mitigating the designated changes in fair value of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting the changes in fair value of the hedged items. The Company assesses the effectiveness of its designated hedges on an individual currency basis. If the ratio obtained with this method is within the range of 80% to 125% , the Company considers the hedge effective. The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the fair value of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. To the extent that the Company discontinues hedge accounting, because, based on management’s assessment, the derivative no longer qualifies as an effective hedge, the derivative will continue to be carried in the Consolidated Balance Sheets at its fair value, with changes in its fair value recognized in current period net income through foreign exchange gains (losses). Cash Flow Hedges The Company uses derivative instruments in the form of interest rate swaps to manage the interest rate exposure associated with certain assets and liabilities. These derivatives are recorded at fair value. Changes in the fair value of a derivative that is designated and qualifies as a cash flow hedge are recorded in accumulated other comprehensive income (“AOCI”) and are reclassified into earnings when the variability of the cash flow of the hedged item impacts earnings. Gains and losses on derivative contracts that are reclassified from AOCI to current period earnings are included in the line item in the Consolidated Statements of Income and Comprehensive Income in which the cash flows of the hedged item are recorded. Any hedge ineffectiveness is recorded immediately in current period earnings. To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in cash flow of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting the changes in cash flows of the hedged items. The Company assesses the effectiveness of its designated hedges on an individual contract basis. The Company currently applies the long haul method when assessing the hedge’s effectiveness. The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the cash flows of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. When hedge accounting is discontinued because the Company becomes aware that it is not probable that the forecasted transaction will occur, the derivative continues to be carried on the balance sheet at its fair value, and gains and losses that were included as part of AOCI are reclassified and recognized immediately in earnings.
Cash and cash equivalents	The Company considers time deposits and money market funds with an original maturity of one month or less as equivalent to cash.
Foreign exchange	The U.S. dollar is the functional currency of the Company and the majority of its subsidiaries. For these companies, monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rates in effect at the balance sheet date and revenues and expenses denominated in foreign currencies are translated at the prevailing exchange rate on the transaction date with the resulting foreign exchange gains and losses included in earnings. Non-monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rate in effect at the time of the underlying transaction. Assets and liabilities of subsidiaries whose functional currency is not the U.S. dollar are translated at prevailing year end exchange rates. Revenue and expenses of such foreign operations are translated at average exchange rates during the year. The net effect of translation differences between functional and reporting currencies in foreign operations, net of applicable deferred income taxes, is included in AOCI.
Stock plans	The Company accounts for its stock plans in accordance with the ASC Topic 718 “Compensation - Stock Compensation.” Accordingly, the Company recognizes the compensation expense for stock option grants, restricted share grants and performance share awards based on the fair value of the award on the date of grant over the requisite service period.
Warrants	The Company has accounted for certain warrant contracts issued to our sponsoring investors in conjunction with the capitalization of the Company, and which may be settled by the Company using either the physical settlement or net-share settlement methods, in accordance with ASC Topic 815 “Derivatives and Hedging, Contracts in Entity’s Own Equity. ” Accordingly, the fair value of these warrants has been recorded in equity as an addition to additional paid-in capital.
Earnings per share	Basic earnings per common share is calculated in accordance with ASC Topic 260 “ Earnings per Share ” by dividing net income available to common shareholders by the weighted average number of common shares outstanding. Earnings per diluted common share are based on the weighted average number of common shares and share equivalents excluding any anti-dilutive effects of warrants, options and other awards under stock plans.
Income taxes and uncertain tax provisions	Deferred tax assets and liabilities are recorded in accordance with ASC Topic 740 “ Income Taxes .” Consistent with ASC 740, the Company records deferred income taxes which reflect operating losses and tax credits carried forward and the tax effect of the temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and their respective tax bases. The Company and its Bermuda domiciled subsidiaries are not subject to any income, withholding or capital gains taxes under current Bermuda law. The Company has operating subsidiaries in various other jurisdictions around the world, including but not limited to the U.K., U.S., Switzerland, Luxembourg and Canada that are subject to relevant taxes in those jurisdictions. The Company recognizes the tax benefits of uncertain tax positions only where the position is more likely than not to be sustained upon examination by tax authorities based upon the technical merits of the position. Based on the more-likely-than-not recognition threshold, we must presume that the tax position will be subject to examination by a taxing authority with full knowledge of all relevant information. If the recognition threshold is met, then the tax position is measured at the largest amount of benefit that is more than 50% likely of being realized upon ultimate settlement. The Company classifies all interest and penalties related to uncertain tax positions in income tax expenses.
Business combinations, goodwill and other intangible assets	The Company accounts for business combinations in accordance with ASC Topic 805 “Business Combinations” and goodwill and other intangible assets that arise from business combinations in accordance with ASC Topic 350 “Intangibles – Goodwill and Other .” A purchase price paid that is in excess of the fair value of the net assets acquired (“goodwill”) arising from a business combination is recorded as an asset, and is not amortized. Where the fair value of the net assets acquired exceeds the consideration paid (“negative goodwill”), the acquirer will record a gain as a result of the bargain purchase, to be recognized through the Consolidated Statements of Income and Comprehensive Income at the close of the transaction. Other intangible assets with a finite life are amortized over the estimated useful life of the asset, whereas other intangible assets with an indefinite useful life are not amortized. Goodwill and other intangible assets are assessed for impairment on an annual basis or more frequently if events or changes in circumstances indicate that it is more likely than not that an impairment exists. Such events or circumstances may include an economic downturn in a geographic market or change in the assessment of future operations. In performing this assessment, the Company may first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the quantitative goodwill impairment test. Similarly, the Company may first assess qualitative factors to determine whether it is more likely than not that an other intangible asset is impaired as a basis for determining whether it is necessary to perform the quantitative impairment test. The factors assessed in making this determination included the overall insurance industry outlook, business strategy, premium rates, earnings sustainability, market capitalization and the regulatory and political environment. If goodwill or other intangible assets are impaired, they are written down to their fair value with a corresponding expense reflected in the Consolidated Statements of Income and Comprehensive Income.
Variable interest entities	The Company determines whether it has relationships with entities defined as VIEs in accordance with ASC Topic 810 “ Consolidation. ” A VIE is consolidated by the variable interest holder that is determined to be the primary beneficiary. An entity in which the Company holds a variable interest is a VIE if any of the following conditions exist: (a) the total equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support, (b) as a group, the holders of equity investment at risk lack either the direct or indirect ability through voting rights or similar rights to make decisions about an entity’s activities that most significantly impact the entity’s economic performance or the obligation to absorb the expected losses or right to receive the expected residual returns, or (c) the voting rights of some investors are disproportionate to their obligation to absorb the expected losses of the entity, their rights to receive the expected residual returns of the entity, or both and substantially all of the entity’s activities either involve or are conducted on behalf of an investor with disproportionately few voting rights. The primary beneficiary is defined as the variable interest holder that is determined to have the controlling financial interest as a result of having both (a) the power to direct the activities of a VIE that most significantly impact the economic performance of the VIE and (b) the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. At inception of the VIE, as well as following an event that requires reassessment, the Company determines whether it is the primary beneficiary based on the facts and circumstances surrounding each entity. The Company consolidates all VOEs in which it has a controlling financial interest and all VIEs in which it is considered to be the primary beneficiary.
Noncontrolling interest	The Company accounts for its noncontrolling interests in accordance with ASC Topic 810 “ Consolidation .” Redeemable noncontrolling interests are presented as a mezzanine item, between liabilities and shareholders’ equity, in the Company’s Consolidated Balance Sheet and the non-redeemable noncontrolling interests are presented within shareholders’ equity in the Company’s Consolidated Balance Sheets and Consolidated Statements of Shareholders’ Equity. The net (income) loss attributable to noncontrolling interests is presented separately in the Company’s Consolidated Statements of Income and Comprehensive Income.

Business combination (Tables)

Business combination (Tables)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Composition of purchase price and fair value of net assets acquired	The fair value of net assets acquired, including pro forma U.S. GAAP adjustments, are summarized as follows: Total purchase price $ 692,305 Assets acquired Cash and cash equivalents $ 48,760 Investments 1,126,185 Receivables 37,848 Other assets 19,418 Tangible assets acquired 1,232,211 Intangible asset - State licenses $ 12,325 Intangible asset - Brand name 5,756 Intangible asset - Distribution network 4,651 Intangible asset - Technology 2,323 Intangible assets acquired $ 25,055 Liabilities acquired Net loss reserves and paid losses recoverable $ 523,315 Unearned premiums, net of expenses 135,686 Other liabilities 81,464 Liabilities acquired 740,465 Excess purchase price (goodwill) as at December 31, 2014 $ 175,504 Measurement period adjustments (a) 861 Excess purchase price (goodwill) as at December 31, 2015 $ 176,365 (a) During the year ended December 31, 2015, measurement period adjustments of $861 were made to certain other assets, net of taxes.
Pro forma information	The unaudited pro forma data is for informational purposes only and does not necessarily represent results that would have occurred if the transaction had taken place on the basis assumed above. Year Ended December 31, 2014 (Dollars in thousands) Unaudited Net premiums earned $ 2,216,349 Net operating income $ 481,179 Net income $ 448,071
Summary of results of acquired company since acquisition	The following selected audited information has been provided to present a summary of the results of Western World that have been included in the Consolidated Financial Statements for the year ended December 31, 2014. From Acquisition Date to (Dollars in thousands) December 31, 2014 Net premiums written $ 58,807 Total revenue 78,325 Total expenses (66,882 ) Net income $ 11,443

Goodwill and other intangible43

Goodwill and other intangible assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Analysis of goodwill by segment	The following table presents a reconciliation of the beginning and ending goodwill and other intangible assets for the years ended December 31, 2016 and 2015 : Year Ended December 31, 2016 Goodwill Other Intangible Assets Talbot Western World Total With a Finite Life With an Indefinite Life Total Balance, beginning of year $ 20,393 $ 176,365 $ 196,758 $ 17,090 $ 104,168 $ 121,258 Amortization — — — (5,666 ) — (5,666 ) Balance, end of year $ 20,393 $ 176,365 $ 196,758 $ 11,424 $ 104,168 $ 115,592 Year Ended December 31, 2015 Goodwill Other Intangible Assets Talbot Western World Total With a Finite Life With an Indefinite Life Total Balance, beginning of year $ 20,393 $ 175,504 $ 195,897 $ 22,756 $ 104,168 $ 126,924 Amortization — — — (5,666 ) — (5,666 ) Measurement period adjustments — 861 861 — — — Balance, end of year $ 20,393 $ 176,365 $ 196,758 $ 17,090 $ 104,168 $ 121,258
Analysis of carrying value and accumulated amortization of intangible assets by type	The gross carrying value, accumulated amortization and net carrying value of other intangible assets by type as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Other intangible assets with a finite life Trade name and customer relationships $ 18,189 $ (13,406 ) $ 4,783 $ 18,189 $ (12,187 ) $ 6,002 Distribution network 39,831 (34,468 ) 5,363 39,831 (30,485 ) 9,346 Technology 2,323 (1,045 ) 1,278 2,323 (581 ) 1,742 Total $ 60,343 $ (48,919 ) $ 11,424 $ 60,343 $ (43,253 ) $ 17,090 Other intangible assets with an indefinite life Syndicate capacity $ 91,843 n/a $ 91,843 $ 91,843 n/a $ 91,843 State licenses 12,325 n/a 12,325 12,325 n/a 12,325 Total $ 104,168 $ 104,168 $ 104,168 $ 104,168
Estimated remaining amortization expense	The estimated remaining amortization expense for the Company’s other intangible assets with a finite life is as follows: Total Remaining Amortization Expense 2017 $ 3,585 2018 1,505 2019 1,389 2020 1,041 2021 1,041 2022 and thereafter 2,863 $ 11,424

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Amortized cost (or cost), and estimated fair value of investments	The amortized cost (or cost) and fair value of the Company’s investments as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Amortized Cost or Cost Fair Value Amortized Fair Value Managed investments U.S. government and government agency $ 809,392 $ 804,126 $ 940,428 $ 937,202 Non-U.S. government and government agency 245,651 240,791 241,549 237,968 U.S. states, municipalities and political subdivisions 271,742 271,830 299,929 301,289 Agency residential mortgage-backed securities 684,490 679,595 606,676 610,582 Non-agency residential mortgage-backed securities 15,858 15,477 27,025 26,920 U.S. corporate 1,540,036 1,534,508 1,503,614 1,489,951 Non-U.S. corporate 418,520 410,227 453,178 446,570 Bank loans 579,121 570,399 592,981 576,211 Asset-backed securities 528,563 526,814 440,363 437,124 Commercial mortgage-backed securities 333,740 330,932 263,310 260,135 Total fixed maturities 5,427,113 5,384,699 5,369,053 5,323,952 Short-term investments 228,574 228,386 237,349 237,369 Other investments Fund of hedge funds 1,457 955 1,457 1,417 Hedge funds 11,292 17,381 14,018 20,980 Private equity investments 72,814 89,809 53,489 63,771 Fixed income investment funds 241,536 242,093 188,121 188,721 Overseas deposits 50,106 50,106 54,484 54,484 Mutual funds 2,925 5,368 4,394 7,483 Total other investments 380,130 405,712 315,963 336,856 Investments in investment affiliates (a) 84,840 100,431 69,794 87,673 Total managed investments $ 6,120,657 $ 6,119,228 $ 5,992,159 $ 5,985,850 Non-managed investments Catastrophe bonds $ 157,486 $ 158,331 $ 187,847 $ 186,379 Short-term investments 2,567,784 2,567,784 1,704,266 1,704,266 Total non-managed investments 2,725,270 2,726,115 1,892,113 1,890,645 Total investments $ 8,845,927 $ 8,845,343 $ 7,884,272 $ 7,876,495 (a) The Company’s investments in investment affiliates have been treated as equity method investments with the corresponding gains and losses recorded in income as “Income (loss) from investment affiliates.”
Investment ratings on fixed maturities	The following table sets forth certain information regarding the investment ratings of the Company’s fixed maturity investments as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Fair Value % of Total Fair Value % of Total Managed fixed maturities AAA $ 2,405,597 43.4 % $ 2,367,642 43.0 % AA 538,289 9.7 % 569,386 10.3 % A 1,081,949 19.5 % 1,031,326 18.7 % BBB 740,861 13.4 % 691,538 12.6 % Total investment grade managed fixed maturities 4,766,696 86.0 % 4,659,892 84.6 % BB 213,568 3.9 % 235,724 4.3 % B 177,737 3.2 % 179,069 3.2 % CCC 13,371 0.2 % 5,706 0.1 % CC — 0.0 % 1,015 0.0 % NR 213,327 3.8 % 242,546 4.4 % Total non-investment grade managed fixed maturities 618,003 11.1 % 664,060 12.0 % Total managed fixed maturities $ 5,384,699 97.1 % $ 5,323,952 96.6 % Non-managed fixed maturities BBB $ — 0.0 % $ 1,911 0.0 % Total investment grade non-managed catastrophe bonds — 0.0 % 1,911 0.0 % BB 29,731 0.6 % 70,962 1.3 % B 4,524 0.1 % 30,698 0.6 % NR 124,076 2.2 % 82,808 1.5 % Total non-investment grade non-managed catastrophe bonds 158,331 2.9 % 184,468 3.4 % Total non-managed fixed maturities 158,331 2.9 % 186,379 3.4 % Total fixed maturities $ 5,543,030 100.0 % $ 5,510,331 100.0 %
Fixed maturities investments by contractual maturity	The amortized cost and estimated fair value amounts for the Company’s fixed maturity investments held at December 31, 2016 and 2015 are shown below by contractual maturity. Actual maturity may differ from contractual maturity because certain borrowers may have the right to call or prepay certain obligations with or without call or prepayment penalties. December 31, 2016 December 31, 2015 Amortized Cost Fair Value Amortized Cost Fair Value Managed fixed maturities Due in one year or less $ 350,733 $ 346,161 $ 367,132 $ 366,019 Due after one year through five years 2,954,856 2,933,146 2,965,920 2,936,053 Due after five years through ten years 430,365 426,647 548,183 539,083 Due after ten years 128,508 125,927 150,444 148,036 3,864,462 3,831,881 4,031,679 3,989,191 Asset-backed and mortgage-backed securities 1,562,651 1,552,818 1,337,374 1,334,761 Total managed fixed maturities $ 5,427,113 $ 5,384,699 $ 5,369,053 $ 5,323,952 Non-managed catastrophe bonds Due in one year or less $ 43,664 $ 45,418 $ 7,504 $ 7,544 Due after one year through five years 112,572 111,656 165,093 163,575 Due after five years through ten years 1,250 1,257 15,250 15,260 Due after ten years — — — — Total non-managed fixed maturities 157,486 158,331 187,847 186,379 Total fixed maturities $ 5,584,599 $ 5,543,030 $ 5,556,900 $ 5,510,331
Other investments	The following tables set forth certain information regarding the Company’s other investments as at December 31, 2016 and 2015 : December 31, 2016 Fair Value Investments with redemption restrictions Investments without redemption restrictions Redemption frequency (a) Redemption notice period (a) Fund of hedge funds $ 955 $ 955 $ — Hedge funds 17,381 17,381 — Private equity investments 89,809 89,809 — Fixed income investment funds 242,093 211,151 30,942 Daily 2 days Overseas deposits 50,106 50,106 — Mutual funds 5,368 — 5,368 Daily Daily Total other investments $ 405,712 $ 369,402 $ 36,310 December 31, 2015 Fair Value Investments with redemption restrictions Investments without redemption restrictions Redemption frequency (a) Redemption notice period (a) Fund of hedge funds $ 1,417 $ 1,417 $ — Hedge funds 20,980 20,980 — Private equity investments 63,771 63,771 — Fixed income investment funds 188,721 167,910 20,811 Daily 2 days Overseas deposits 54,484 54,484 — Mutual funds 7,483 — 7,483 Daily Daily Total other investments $ 336,856 $ 308,562 $ 28,294 (a) The redemption frequency and notice periods only apply to investments without redemption restrictions.
Net investment income	Net investment income was derived from the following sources: Years Ended December 31, 2016 2015 2014 Managed investments Fixed maturities and short-term investments $ 119,085 $ 113,627 $ 93,044 Other investments 27,860 13,307 5,111 Cash and cash equivalents and restricted cash 2,939 1,911 5,106 Securities lending income 55 16 11 Total gross investment income 149,939 128,861 103,272 Investment expenses (8,221 ) (7,695 ) (7,472 ) Total managed net investment income $ 141,718 $ 121,166 $ 95,800 Non managed investments Fixed maturities and short-term investments $ 6,931 $ 6,528 $ 4,204 Cash and cash equivalents and restricted cash 1,736 130 82 Total non-managed net investment income 8,667 6,658 4,286 Total net investment income $ 150,385 $ 127,824 $ 100,086
Analysis of net realized gains (losses) and the change in net unrealized (losses) gains on investments	The following table sets forth an analysis of net realized gains and the change in net unrealized gains (losses) on investments: Years Ended December 31, 2016 2015 2014 Managed fixed maturities, short-term and other investments Gross realized gains $ 22,491 $ 15,678 $ 20,201 Gross realized (losses) (7,811 ) (13,980 ) (8,041 ) Net realized gains on investments 14,680 1,698 12,160 Change in net unrealized gains (losses) on investments 14,106 (32,007 ) (1,030 ) Total net realized and change in net unrealized gains (losses) on managed investments $ 28,786 $ (30,309 ) $ 11,130 Non-managed fixed maturities, short-term and other investments Gross realized gains $ 1,086 $ 611 $ 2,757 Gross realized (losses) (9 ) (11 ) — Net realized gains on investments 1,077 600 2,757 Change in net unrealized gains (losses) on investments 2,765 (388 ) (1,812 ) Total net realized and change in net unrealized gains on non-managed investments 3,842 212 945 Total net realized and change in net unrealized gains (losses) on total investments $ 32,628 $ (30,097 ) $ 12,075
Investment Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Reconciliation of beginning and ending investment in affiliate balances	The following table presents a reconciliation of the Company’s beginning and ending investments in investment affiliates for the years ended December 31, 2016 and 2015 : Years Ended December 31, 2016 2015 Investment affiliates, beginning of year $ 87,673 $ 63,506 Net capital contributions 14,841 19,886 (Loss) income from investment affiliate (2,083 ) 4,281 Investment affiliates, end of year $ 100,431 $ 87,673
Schedule of equity method investments	The following table presents the Company’s investments in the partnerships as at December 31, 2016 and 2015: December 31, 2016 Investment at cost Voting ownership % Equity ownership % Carrying value Aquiline II Partnership $ 46,871 — % 8.1 % $ 61,999 Aquiline III Partnership 37,969 — % 9.0 % 38,432 Total $ 84,840 $ 100,431 December 31, 2015 Investment at cost Voting ownership % Equity ownership % Carrying value Aquiline II Partnership $ 55,904 — % 8.1 % $ 73,880 Aquiline III Partnership 13,890 — % 13.7 % 13,793 Total $ 69,794 $ 87,673

Fair value measurements (Tables

Fair value measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair value hierarchy - allocation of investments	At December 31, 2016 , the Company’s investments were allocated between Levels 1, 2 and 3 as follows: Level 1 Level 2 Level 3 Fair value based on NAV practical expedient Total Managed investments U.S. government and government agency $ — $ 804,126 $ — $ — $ 804,126 Non-U.S. government and government agency — 240,791 — — 240,791 U.S. states, municipalities and political subdivisions — 271,830 — — 271,830 Agency residential mortgage-backed securities — 679,595 — — 679,595 Non-agency residential mortgage-backed securities — 15,477 — — 15,477 U.S. corporate — 1,534,508 — — 1,534,508 Non-U.S. corporate — 410,227 — — 410,227 Bank loans — 323,903 246,496 — 570,399 Asset-backed securities — 502,883 23,931 — 526,814 Commercial mortgage-backed securities — 330,932 — — 330,932 Total fixed maturities — 5,114,272 270,427 — 5,384,699 Short-term investments 209,651 18,735 — — 228,386 Other investments Fund of hedge funds — — — 955 955 Hedge funds — — — 17,381 17,381 Private equity investments — — — 89,809 89,809 Fixed income investment funds — 30,941 12,168 198,984 242,093 Overseas deposits — — — 50,106 50,106 Mutual funds — 5,368 — — 5,368 Total other investments — 36,309 12,168 357,235 405,712 Investments in investment affiliates (a) — — — — 100,431 Total managed investments $ 209,651 $ 5,169,316 $ 282,595 $ 357,235 $ 6,119,228 Non-managed investments Catastrophe bonds $ — $ 109,956 $ 48,375 $ — $ 158,331 Short-term investments 2,567,784 — — — 2,567,784 Total non-managed investments 2,567,784 109,956 48,375 — 2,726,115 Total investments $ 2,777,435 $ 5,279,272 $ 330,970 $ 357,235 $ 8,845,343 (a) In accordance with ASC Topic 825 “Financial Instruments,” the Company’s investments in investment affiliates have not been classified in the fair value hierarchy. At December 31, 2015 , the Company’s investments were allocated between Levels 1, 2 and 3 as follows: Level 1 Level 2 Level 3 Fair value based on NAV practical expedient Total Managed investments U.S. government and government agency $ — $ 937,202 $ — $ — $ 937,202 Non-U.S. government and government agency — 237,968 — — 237,968 U.S. states, municipalities and political subdivisions — 301,289 — — 301,289 Agency residential mortgage-backed securities — 610,582 — — 610,582 Non-agency residential mortgage-backed securities — 26,920 — — 26,920 U.S. corporate — 1,489,951 — — 1,489,951 Non-U.S. corporate — 446,570 — — 446,570 Bank loans — 343,874 232,337 — 576,211 Asset-backed securities — 437,124 — — 437,124 Commercial mortgage-backed securities — 260,135 — — 260,135 Total fixed maturities — 5,091,615 232,337 — 5,323,952 Short-term investments 222,678 14,691 — — 237,369 Other investments Fund of hedge funds — — — 1,417 1,417 Hedge funds — — — 20,980 20,980 Private equity investments — — — 63,771 63,771 Fixed income investment funds — 20,811 — 167,910 188,721 Overseas deposits — — — 54,484 54,484 Mutual funds — 7,483 — — 7,483 Total other investments — 28,294 — 308,562 336,856 Investments in investment affiliates (a) — — — — 87,673 Total managed investments $ 222,678 $ 5,134,600 $ 232,337 $ 308,562 $ 5,985,850 Non-managed investments Catastrophe bonds $ — $ 172,879 $ 13,500 $ — $ 186,379 Short-term investments 1,704,266 — — — 1,704,266 Total non-managed investments 1,704,266 172,879 13,500 — 1,890,645 Total investments $ 1,926,944 $ 5,307,479 $ 245,837 $ 308,562 $ 7,876,495 (a) In accordance with ASC Topic 825 “Financial Instruments,” the Company’s investments in investment affiliates have not been classified in the fair value hierarchy.
Reconciliation of investments measured at fair value on a recurring basis using Level 3 inputs	The following table presents a reconciliation of the beginning and ending balances for all investments measured at fair value on a recurring basis using Level 3 inputs during the years ended December 31, 2016 and 2015 : Year Ended December 31, 2016 Bank Loans Catastrophe Bonds Fixed Income Investment Funds Asset Backed Securities Total Level 3 investments, beginning of year $ 232,337 $ 13,500 $ — $ — $ 245,837 Purchases 87,345 33,272 12,168 23,896 156,681 Sales (2,389 ) — — — (2,389 ) Settlements (69,496 ) (125 ) — — (69,621 ) Change in net unrealized (losses) gains (1,301 ) 1,728 — 35 462 Level 3 investments, end of year $ 246,496 $ 48,375 $ 12,168 $ 23,931 $ 330,970 Year Ended December 31, 2015 Bank Loans Catastrophe Bonds Total Level 3 investments, beginning of year $ 32,748 $ 17,500 $ 50,248 Purchases 230,070 — 230,070 Sales (1,036 ) (3,989 ) (5,025 ) Settlements (27,429 ) — (27,429 ) Net realized losses — (11 ) (11 ) Change in net unrealized losses (2,016 ) — (2,016 ) Level 3 investments, end of year $ 232,337 $ 13,500 $ 245,837

Variable interest entities (Tab

Variable interest entities (Tables)	12 Months Ended
	Dec. 31, 2016
Variable Interest Entities Disclosure [Abstract]
Summary of notes payable to AlphaCat entities	The following tables present a reconciliation of the beginning and ending notes payable to AlphaCat investors as at December 31, 2016 and 2015: Year Ended December 31, 2016 Variable Funding Notes Structured Notes Total Notes payable to AlphaCat investors, beginning of year $ 75,493 $ — $ 75,493 Issuance of notes payable to AlphaCat investors 311,711 94,326 406,037 Redemption of notes payable to AlphaCat investors (109,712 ) (94,326 ) (204,038 ) Foreign exchange gains 710 — 710 Notes payable to AlphaCat investors, end of year $ 278,202 $ — $ 278,202 Year Ended December 31, 2015 Variable Funding Notes Structured Notes Total Notes payable to AlphaCat investors, beginning of year $ — $ — $ — Issuance of notes payable to AlphaCat investors 75,770 — 75,770 Foreign exchange losses (277 ) — (277 ) Notes payable to AlphaCat investors, end of year $ 75,493 $ — $ 75,493
Total assets and liabilities of the Company's consolidated VIEs	The following table presents the total assets and total liabilities of the Company’s consolidated VIEs, excluding intercompany eliminations, as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Total Assets Total Liabilities Total Assets Total Liabilities AlphaCat sidecars $ 40,041 $ 3,206 $ 206,581 $ 14,804 AlphaCat ILS funds - Lower Risk $ 1,498,276 $ 42,457 $ 1,268,070 $ 143,371 AlphaCat ILS funds - Higher Risk $ 972,633 $ 381,332 $ 522,867 $ 300,122 AlphaCat Re and AlphaCat Master Fund $ 2,510,415 $ 2,510,245 $ 1,615,779 $ 1,615,609 BetaCat ILS funds $ 82,471 $ 30,663 $ 64,221 $ 2,472

Noncontrolling interests (Table

Noncontrolling interests (Tables)	12 Months Ended
	Dec. 31, 2016
Noncontrolling Interest [Abstract]
Reconciliation of beginning and ending balances of noncontrolling interest and redeemable noncontrolling interest	The following tables present a reconciliation of the beginning and ending balances of redeemable noncontrolling interests and noncontrolling interests for the years ended December 31, 2016 and 2015 : Redeemable Noncontrolling Interests Noncontrolling Interests Total Years Ended December 31, Years Ended December 31, Years Ended December 31, 2016 2015 2016 2015 2016 2015 Balance, beginning of year $ 1,111,714 $ 617,791 $ 154,662 $ 292,274 $ 1,266,376 $ 910,065 Issuance of shares 393,450 499,200 171,674 9,600 565,124 508,800 Income attributable to noncontrolling interests 100,852 71,418 22,511 21,546 123,363 92,964 Redemption of shares / Distributions (78,015 ) (76,695 ) (182,870 ) (168,758 ) (260,885 ) (245,453 ) Balance, end of year $ 1,528,001 $ 1,111,714 $ 165,977 $ 154,662 $ 1,693,978 $ 1,266,376

Investment in operating affil48

Investment in operating affiliate (Tables) - Operating Affiliates	12 Months Ended
	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Reconciliation of beginning and ending investment in affiliate balances	The following table presents a reconciliation of the beginning and ending investment in PaCRe for the years ended December 31, 2016 and 2015 : Years Ended December 31, 2016 2015 Operating affiliate, beginning of year $ 392 $ 50,944 Return of investment (369 ) (46,603 ) Loss from operating affiliate (23 ) (3,949 ) Operating affiliate, end of year $ — $ 392
Schedule of equity method investments	The following table presents the Company’s investment in PaCRe as at December 31, 2015 : Investment at cost Voting ownership % Equity ownership % Carrying value Investment in PaCRe $ 392 100.0 % 10.0 % $ 392

Derivative instruments (Tables)

Derivative instruments (Tables)	12 Months Ended
	Dec. 31, 2016
Derivative [Line Items]
Location and amount of gains and losses related to derivative instruments reported on in the comprehensive income and earnings	The following table provides the total impact on other comprehensive income (loss) and earnings relating to the derivative instruments formally designated as cash flow hedges along with the impact of the related hedged items for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, Interest rate swap contracts 2016 2015 2014 Amount of effective portion recognized in other comprehensive income $ 10,584 $ 13,740 $ 13,302 Amount of effective portion subsequently reclassified to earnings $ (10,861 ) $ (12,899 ) $ (13,074 ) Amount of ineffective portion excluded from effectiveness testing $ 277 $ (841 ) $ (228 )
Not designated as hedging instruments
Derivative [Line Items]
Location and fair value amount of derivative instruments reported on the balance sheet	The following table summarizes information on the classification and amount of the fair value of derivatives not designated as hedging instruments for accounting purposes within the Company’s Consolidated Balance Sheets as at December 31, 2016 and December 31, 2015 : December 31, 2016 December 31, 2015 Derivatives not designated as hedging instruments Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Foreign currency forward contracts $ 181,375 $ 2,351 $ 3,421 $ 255,840 $ 2,601 $ 3,211 (a) Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses, respectively, within the Company’s Consolidated Balance Sheets.
Location and amount of gains and losses related to derivatives reported in the income statements	The following table summarizes information on the classification and net impact on earnings, recognized in the Company’s Consolidated Statements of Income and Comprehensive Income relating to the foreign currency forward and interest rate swap contracts that were not designated as hedging instruments for accounting purposes during the years ended December 31, 2016 , 2015 and 2014 : Derivatives not designated as hedging instruments Classification of gains (losses) recognized in earnings Years Ended December 31, 2016 2015 2014 Foreign currency forward contracts Foreign exchange gains losses $ (1,667 ) $ (610 ) $ — Foreign currency forward contracts Other insurance related income and other income $ 142 $ 139 $ (133 ) Interest rate swap contracts (a) Net realized gains on investments $ 8,518 $ — $ — (a) Relates to net realized gains on two interest rate swap contracts which were entered into and terminated during the year ended December 31, 2016 to partially offset the impact of interest rate increases on the Company’s fixed maturity investment portfolio.
Designated as hedging instruments
Derivative [Line Items]
Location and fair value amount of derivative instruments reported on the balance sheet	The following table summarizes information on the classification and amount of the fair value of derivatives designated as hedging instruments for accounting purposes on the Consolidated Balance Sheets as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Derivatives designated as hedging instruments Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Notional Exposure Asset Derivative at Fair Value (a) Liability Derivative at Fair Value (a) Interest rate swap contracts $ 552,263 $ 20 $ 1,479 $ 552,263 $ 21 $ 1,942 (a) Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses, respectively, within the Company’s Consolidated Balance Sheets.
Location and amount of gains and losses related to derivatives reported in the income statements	The following table provides the net impact on earnings, recognized in income within foreign exchange gains (losses), relating to the derivative instruments formally designated as fair value hedges for accounting purposes along with the impact of the related hedged items for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, Foreign currency forward contracts 2016 2015 2014 Amount of loss recognized in income on derivative $ — $ (12,279 ) $ (9,651 ) Amount of gain on hedged item recognized in income attributable to risk being hedged $ — $ 12,279 $ 9,651 Amount of gain recognized in income on derivative (ineffective portion) $ — $ — $ —

Premiums receivable (Tables)

Premiums receivable (Tables)	12 Months Ended
	Dec. 31, 2016
Premiums Receivable Disclosure [Abstract]
Components of premiums receivable	The following is a breakdown of the components of premiums receivable at December 31, 2016 and 2015 : Year Ended December 31, 2016 Premiums in course of collection Premiums accrued but unbilled Total Premiums receivable, beginning of year $ 95,152 $ 563,530 $ 658,682 Change during year 6,250 60,458 66,708 Premiums receivable, end of year $ 101,402 $ 623,988 $ 725,390 Year Ended December 31, 2015 Premiums in course of collection Premiums accrued but unbilled Total Premiums receivable, beginning of year $ 84,901 $ 621,566 $ 706,467 Change during year 10,251 (58,036 ) (47,785 ) Premiums receivable, end of year $ 95,152 $ 563,530 $ 658,682

Reserve for losses and loss e51

Reserve for losses and loss expenses (Tables)	12 Months Ended
	Dec. 31, 2016
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Components of reserves	The following table summarizes the total reserve for losses and loss expenses as at December 31, 2016 and 2015 : December 31, 2016 December 31, 2015 Case reserves $ 1,237,772 $ 1,278,697 IBNR 1,757,423 1,717,870 Total reserve for losses and loss expenses $ 2,995,195 $ 2,996,567
Reserve for losses and loss expenses	The following table represents an analysis of paid and unpaid losses and loss expenses incurred and a reconciliation of the beginning and ending unpaid losses and loss expenses for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Reserve for losses and loss expenses, beginning of year $ 2,996,567 $ 3,243,147 $ 3,047,933 Loss reserves recoverable (350,586 ) (377,466 ) (370,154 ) Net reserves for losses and loss expenses, beginning of year 2,645,981 2,865,681 2,677,779 Net reserves acquired — — 525,091 Increase (decrease) in net reserves for losses and loss expenses in respect of losses occurring in: Current year 1,281,289 1,283,970 1,024,256 Prior years (a) (216,192 ) (306,137 ) (259,241 ) Total incurred losses and loss expenses (a) 1,065,097 977,833 765,015 Less net losses and loss expenses paid in respect of losses occurring in: Current year (389,234 ) (326,167 ) (245,084 ) Prior years (725,168 ) (841,672 ) (818,569 ) Total net paid losses (1,114,402 ) (1,167,839 ) (1,063,653 ) Foreign exchange gain (31,902 ) (29,694 ) (38,551 ) Net reserve for losses and loss expenses, end of year 2,564,774 2,645,981 2,865,681 Loss reserves recoverable 430,421 350,586 377,466 Reserve for losses and loss expenses, end of year $ 2,995,195 $ 2,996,567 $ 3,243,147 Incurred losses and loss expenses comprise: Years Ended December 31, 2016 2015 2014 Gross losses and loss expenses (a) $ 1,257,054 $ 1,083,695 $ 826,826 Reinsurance balances recoverable (191,957 ) (105,862 ) (61,811 ) Net incurred losses and loss expenses (a) $ 1,065,097 $ 977,833 $ 765,015 (a) Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was fully amortized to income through a reduction in losses and loss expenses of $10,979 and $4,607 during the years ended December 31, 2015 and 2014, respectively
Prior year development by segment and line of business	The net favorable development on prior accident years by segment and line of business for the years ended December 31, 2016 , 2015 and 2014 was as follows: Year Ended December 31, 2016 Property Marine Specialty Liability Total Validus Re $ (57,888 ) $ (24,435 ) $ (36,210 ) $ — $ (118,533 ) Talbot (38,368 ) (11,738 ) (35,704 ) — (85,810 ) Western World (2,701 ) — — (6,411 ) (9,112 ) AlphaCat (1,858 ) — (879 ) — (2,737 ) Net favorable development $ (100,815 ) $ (36,173 ) $ (72,793 ) $ (6,411 ) $ (216,192 ) The Validus Re segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses along with favorable development on the 2015 Chilean Earthquake and 2015 Tianjin port explosion loss events partially offset by adverse development on events in the marine lines primarily related to receipt of a loss advice on an individual marine policy that incepted during the second half of 2015. The Talbot segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses partially offset by adverse development on events in the marine lines primarily related to receipt of a loss advice on an individual marine policy that incepted during the second half of 2015. The Western World segment experienced favorable development on prior accident years principally due to favorable development on attritional losses. Year Ended December 31, 2015 Property Marine Specialty Liability Total (a) Validus Re $ (70,343 ) $ (39,460 ) $ (18,813 ) $ — $ (128,616 ) Talbot (52,393 ) (63,920 ) (30,044 ) — (146,357 ) Western World (a) (6,045 ) — — (16,922 ) (22,967 ) AlphaCat (8,197 ) — — — (8,197 ) Net favorable development (a) $ (136,978 ) $ (103,380 ) $ (48,857 ) $ (16,922 ) $ (306,137 ) The Validus Re segment experienced favorable development on prior accident years primarily due to favorable development on Superstorm Sandy, a 2012 loss event, and attritional losses. The Talbot segment experienced favorable development on prior accident years primarily due to favorable development on attritional losses and certain events, including the Thailand floods, which was a 2011 loss event. The Western World segment experienced favorable development on prior accident years primarily due to the amortization of the fair value adjustment made at the acquisition date as well as favorable development on attritional losses. Year Ended December 31, 2014 Property Marine Specialty Liability Total Validus Re $ (76,064 ) $ (6,830 ) $ (4,706 ) $ — $ (87,600 ) Talbot (53,779 ) (31,397 ) (55,990 ) — (141,166 ) Western World (a) 1,023 — — (12,263 ) (11,240 ) AlphaCat (19,235 ) — — — (19,235 ) Net favorable development (a) $ (148,055 ) $ (38,227 ) $ (60,696 ) $ (12,263 ) $ (259,241 ) (a) Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was fully amortized to income through a reduction in losses and loss expenses of $10,979 and $4,607 during the years ended December 31, 2015 and 2014, respectively.
Claims development table	Validus Re - Property Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 397,635 $ 321,956 $ 309,344 $ 282,517 $ 280,411 $ 19,108 n/a 2013 174,722 156,233 141,203 132,830 7,233 n/a 2014 108,206 102,273 95,392 6,757 n/a 2015 154,923 118,484 41,177 n/a 2016 149,263 86,564 n/a Total $ 776,380 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 67,004 149,433 202,141 225,518 234,256 2013 17,325 63,974 101,158 114,263 2014 25,346 63,415 78,509 2015 16,029 57,882 2016 26,522 Total $ 511,432 Reserves for losses and loss expenses, before 2012, net of reinsurance (a) $ 154,539 Reserves for losses and loss expenses, net of reinsurance $ 419,487 (a) Includes reserves for losses and loss expenses, net of reinsurance, of $77,790 and $10,614 related to Flagstone and IPC, respectively. Validus Re - Marine Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 195,163 $ 226,817 $ 225,131 $ 218,734 $ 216,673 $ 19,725 n/a 2013 76,776 74,022 63,630 61,210 7,347 n/a 2014 63,732 42,991 35,910 7,418 n/a 2015 129,864 119,490 55,557 n/a 2016 68,531 49,619 n/a Total $ 501,814 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 11,356 94,052 148,628 169,420 178,172 2013 11,784 28,996 39,493 44,512 2014 7,013 11,749 17,383 2015 3,723 16,180 2016 8,801 Total $ 265,048 Reserves for losses and loss expenses, before 2012, net of reinsurance (a) $ 64,750 Reserves for losses and loss expenses, net of reinsurance $ 301,516 (a) Includes reserves for losses and loss expenses, net of reinsurance, of $15,178 and $1,537 related to Flagstone and IPC, respectively. Validus Re - Specialty Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 53,798 $ 54,573 $ 49,263 $ 47,428 $ 46,626 $ 733 n/a 2013 182,297 190,470 178,736 174,219 1,974 n/a 2014 213,911 208,508 200,649 8,372 n/a 2015 296,554 279,766 32,236 n/a 2016 295,872 128,761 n/a Total $ 997,132 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 17,716 $ 41,156 $ 44,037 $ 44,942 $ 45,332 2013 99,340 157,688 164,366 166,814 2014 95,765 162,056 176,202 2015 177,776 235,819 2016 149,502 Total $ 773,669 Reserves for losses and loss expenses, before 2012, net of reinsurance (a) $ 67,909 Reserves for losses and loss expenses, net of reinsurance $ 291,372 (a) Includes reserves for losses and loss expenses, net of reinsurance, of $41,091 and $5,743 related to Flagstone and IPC, respectively. (ii) Talbot The Talbot loss development tables have been produced by line of business for accident years 2012 through to 2016. The Company determined that it was impracticable to produce IBNR by accident year for years prior to 2012 as the Company did not record this data for years prior to 2012 and as such, did not allocate IBNR by line of business for these years. Talbot writes treaty reinsurance business along with business through binders and lineslips and for this business the Company does not receive or maintain claims count information associated with its reserved losses therefore, the Company has determined that it is impracticable to provide claims count information. Talbot - Property Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 135,923 $ 112,488 $ 100,748 $ 101,387 $ 100,773 $ 2,413 n/a 2013 118,167 96,814 83,426 81,004 605 n/a 2014 147,259 121,260 114,852 5,528 n/a 2015 138,087 109,608 12,696 n/a 2016 177,771 76,755 n/a Total $ 584,008 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 13,051 $ 61,490 $ 83,824 $ 88,150 $ 92,512 2013 12,813 48,231 67,328 73,267 2014 21,249 74,493 95,945 2015 24,537 63,437 2016 37,880 Total $ 363,041 Reserves for losses and loss expenses, before 2012, net of reinsurance $ 12,180 Reserves for losses and loss expenses, net of reinsurance $ 233,147 Talbot - Marine Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 208,883 $ 203,855 $ 186,278 $ 182,283 $ 178,839 $ 5,154 n/a 2013 189,091 188,991 168,203 161,839 11,372 n/a 2014 180,401 155,361 154,105 13,671 n/a 2015 187,790 192,818 54,285 n/a 2016 159,153 89,536 n/a Total $ 846,754 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 36,491 $ 105,600 $ 136,335 $ 153,550 $ 157,475 2013 38,416 88,494 112,781 125,037 2014 24,433 74,547 102,788 2015 25,300 73,957 2016 35,105 Total $ 494,362 Reserves for losses and loss expenses, before 2012, net of reinsurance $ 44,753 Reserves for losses and loss expenses, net of reinsurance $ 397,145 Talbot - Specialty Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <-------------------------- Unaudited ---------------------------> 2012 $ 151,306 $ 132,735 $ 122,760 $ 120,621 $ 118,869 $ 5,886 n/a 2013 166,450 145,905 132,797 124,208 8,724 n/a 2014 215,960 214,962 198,653 39,248 n/a 2015 152,907 149,031 39,447 n/a 2016 166,604 105,142 n/a Total $ 757,365 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2012 2013 2014 2015 2016 <-------------------------- Unaudited ---------------------------> 2012 $ 25,591 $ 57,906 $ 83,201 $ 87,753 $ 105,888 2013 42,325 77,428 91,940 100,213 2014 41,183 107,882 135,526 2015 35,724 85,397 2016 33,468 Total $ 460,492 Reserves for losses and loss expenses, before 2012, net of reinsurance $ 45,486 Reserves for losses and loss expenses, net of reinsurance $ 342,359 (iii) Western World The Western World loss development tables have been produced by line of business for accident years 2007 through to 2016. The Company has accumulated claims count information by accident year for Western World. The Company’s methodology for determining reported claims count information is on a per claims basis by accident year and is inclusive of claims that are open, closed with payment and closed without payment. Western World - Property Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 8,520 $ 8,161 $ 8,218 $ 8,209 $ 8,209 $ 8,206 $ 8,206 $ 8,207 $ 8,207 $ 8,207 $ — 841 2008 12,094 11,615 11,805 11,762 11,729 11,721 11,724 11,724 11,724 — 412 2009 10,300 10,005 10,039 10,034 10,060 10,060 10,060 10,060 — 784 2010 11,846 11,573 11,507 11,414 11,448 11,438 11,332 — 974 2011 12,588 12,223 12,000 12,134 12,012 12,021 — 1,238 2012 15,506 15,491 15,594 15,556 15,522 — 1,680 2013 21,825 23,561 23,659 23,599 — 1,950 2014 35,612 29,282 28,619 103 2,393 2015 27,879 26,002 135 1,788 2016 46,636 9,324 1,587 Total $ 193,722 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 5,418 $ 7,968 $ 8,192 $ 8,206 $ 8,206 $ 8,206 $ 8,206 $ 8,207 $ 8,207 $ 8,207 2008 8,895 11,288 11,672 11,747 11,714 11,721 11,724 11,724 11,724 2009 8,096 9,948 9,942 10,003 10,060 10,060 10,060 10,060 2010 8,563 10,521 10,905 10,854 10,882 10,903 11,287 2011 9,797 12,000 11,976 12,027 12,009 12,021 2012 11,166 14,838 15,435 15,513 15,522 2013 15,568 22,647 23,104 23,561 2014 21,913 27,211 27,606 2015 18,981 25,302 2016 29,666 Total $ 174,956 Reserves for losses and loss expenses, before 2007, net of reinsurance $ — Reserves for losses and loss expenses, net of reinsurance $ 18,766 Western World - Liability Incurred Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, December 31, 2016 Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 Total of IBNR Reserves Plus Expected Development on Reported Losses Cumulative Reported Claims Count <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 164,717 $ 162,239 $ 160,117 $ 158,478 $ 154,499 $ 152,163 $ 149,994 $ 107,894 $ 107,350 $ 106,342 $ 1,981 $ 4.727 2008 135,009 135,280 135,330 133,088 131,006 129,559 102,424 102,070 101,478 2,075 4,950 2009 116,474 116,780 116,990 116,463 116,327 98,261 96,235 95,266 2,173 3,955 2010 101,223 108,823 111,675 112,072 105,400 106,066 103,973 3,877 4,205 2011 101,091 107,741 107,827 109,412 109,183 108,301 4,627 4,372 2012 108,981 111,283 133,990 132,562 127,486 9,410 4,649 2013 132,077 165,233 164,428 158,329 17,049 5,990 2014 197,022 197,388 203,592 44,988 7,469 2015 154,184 158,591 76,092 5,152 2016 133,303 104,906 3,156 Total $ 1,296,661 Cumulative Paid Losses and Loss Expenses, Net of Reinsurance Years Ended December 31, Accident Year 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 <------------------------------------------------- Unaudited --------------------------------------------------> 2007 $ 10,723 $ 30,741 $ 58,358 $ 80,218 $ 91,020 $ 96,658 $ 99,978 $ 102,600 $ 103,961 $ 104,038 2008 8,654 28,467 51,165 71,239 82,661 89,433 93,563 95,773 97,475 2009 10,023 30,131 48,255 65,009 77,895 85,644 89,688 90,415 2010 8,215 28,393 51,765 71,430 84,320 92,889 96,309 2011 7,331 27,438 50,197 75,000 88,415 96,780 2012 8,823 31,291 65,437 92,499 108,409 2013 10,159 41,782 77,776 108,613 2014 16,468 52,543 98,848 2015 12,662 39,598 2016 9,873 Total $ 850,358 Reserves for losses and loss expenses, before 2007, net of reinsurance $ 8,944 Reserves for losses and loss expenses, net of reinsurance $ 455,247
Reconciliation of claims development to liability	The table below reconciles the loss development information to the Company’s reserves for losses and loss expenses as at December 31, 2016: December 31, 2016 Reserves for losses and loss expenses, net of reinsurance Validus Re - Property $ 419,487 Validus Re - Marine 301,516 Validus Re - Specialty 291,372 Talbot - Property 233,147 Talbot - Marine 397,145 Talbot - Specialty 342,359 Western World - Property 18,766 Western World - Liability 455,247 Total reserves for losses and loss expenses, net of reinsurance 2,459,039 Loss reserves recoverable Validus Re - Property 42,873 Validus Re - Marine 52,970 Validus Re - Specialty 2,162 Talbot - Property 93,774 Talbot - Marine 125,677 Talbot - Specialty 86,587 Western World - Property 187 Western World - Liability 87,300 Elimination - Intercompany (61,109 ) Total loss reserves recoverable 430,421 Unallocated loss adjustment expenses 51,990 Provisions for uncollectible reinsurance 5,153 Reserves for losses and loss expenses - AlphaCat segment 48,534 Other 58 Total reserves for losses and loss expenses $ 2,995,195
Historical loss duration	The below table summarizes the historic average annual percentage payout of incurred losses by age, net of reinsurance, as of December 31, 2016: Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance December 31, 2016 Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Year 9 Year 10 Validus Re - Property 19.0 % 34.9 % 20.9 % 9.1 % 3.1 % n/a n/a n/a n/a n/a Validus Re - Marine 12.0 % 22.5 % 19.3 % 8.9 % 4.0 % n/a n/a n/a n/a n/a Validus Re - Specialty 51.4 % 34.4 % 5.7 % 1.7 % 0.8 % n/a n/a n/a n/a n/a Talbot - Property 18.2 % 43.4 % 21.5 % 5.8 % 4.3 % n/a n/a n/a n/a n/a Talbot - Marine 19.0 % 31.8 % 16.8 % 8.6 % 2.2 % n/a n/a n/a n/a n/a Talbot - Specialty 24.1 % 30.6 % 15.6 % 5.2 % 15.3 % n/a n/a n/a n/a n/a Western World - Property 73.1 % 22.4 % 2.0 % 0.5 % 0.1 % 0.1 % 0.9 % — % — % — % Western World - Liability 8.1 % 18.9 % 22.9 % 20.1 % 12.0 % 7.2 % 3.7 % 1.8 % 1.5 % 0.1 %

Accounts payable and accrued 52

Accounts payable and accrued expenses (Tables)	12 Months Ended
	Dec. 31, 2016
Accounts Payable and Accrued Liabilities [Abstract]
Components of accounts payable and accrued expenses	The following are the components of accounts payable and accrued expenses: December 31, 2016 December 31, 2015 Accrued interest on debt $ 10,286 $ 10,771 Subscriptions received in advance on AlphaCat ILS funds and sidecars 326,900 412,036 Redemptions/distributions payable to noncontrolling interests 87,674 10,800 Structured notes payable to AlphaCat investors 1,000 — Accrued income attributable to AlphaCat investors 17,068 2,412 Income tax payable 1,036 8,856 Accrued pension liability 16,979 15,722 Trade and compensation payables 126,705 166,734 Total accounts payable and accrued expenses $ 587,648 $ 627,331

Reinsurance (Tables)

Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2016
Reinsurance Disclosures [Abstract]
ScheduleOfReinsuranceRecoverable [Table Text Block]	The Company’s reinsurance balances recoverable at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Loss reserves recoverable on unpaid: Case reserves $ 165,328 $ 135,723 IBNR 265,093 214,863 Total loss reserves recoverable 430,421 350,586 Paid losses recoverable 35,247 23,071 Total reinsurance recoverable $ 465,668 $ 373,657
Effects of reinsurance on premiums written and earned	The effects of reinsurance on premiums written and earned for the years ended December 31, 2016 , 2015 and 2014 were as follows: Year Ended December 31, 2016 Validus Re Talbot Western World AlphaCat Eliminations Total Written Earned Written Earned Written Earned Written Earned Written Earned Written Earned Treaty reinsurance $ 1,111,054 $ 1,060,117 $ 146,296 $ 115,828 $ — $ — $ 270,402 $ 256,085 $ (26,673 ) $ (23,035 ) $ 1,501,079 $ 1,408,995 Facultative reinsurance — — 293,741 307,351 — — — — — — 293,741 307,351 Direct — — 530,665 529,265 323,220 294,376 — — — — 853,885 823,641 Ceded (111,564 ) (116,172 ) (175,729 ) (170,528 ) (22,634 ) (21,144 ) (6,451 ) (6,013 ) 26,673 23,035 (289,705 ) (290,822 ) Total $ 999,490 $ 943,945 $ 794,973 $ 781,916 $ 300,586 $ 273,232 $ 263,951 $ 250,072 $ — $ — $ 2,359,000 $ 2,249,165 Year Ended December 31, 2015 Validus Re Talbot Western World AlphaCat Eliminations Total Written Earned Written Earned Written Earned Written Earned Written Earned Written Earned Treaty reinsurance $ 1,126,759 $ 1,141,184 $ 133,273 $ 136,796 $ — $ — $ 176,126 $ 164,544 $ (42,718 ) $ (45,115 ) $ 1,393,440 $ 1,397,409 Facultative reinsurance — — 325,311 330,472 — — — — — — 325,311 330,472 Direct — — 560,251 570,669 278,504 281,587 — — — — 838,755 852,256 Ceded (149,088 ) (150,971 ) (198,896 ) (199,846 ) (18,877 ) (22,937 ) (4,538 ) (4,609 ) 42,718 45,115 (328,681 ) (333,248 ) Total $ 977,671 $ 990,213 $ 819,939 $ 838,091 $ 259,627 $ 258,650 $ 171,588 $ 159,935 $ — $ — $ 2,228,825 $ 2,246,889 Year Ended December 31, 2014 Validus Re Talbot Western World AlphaCat Eliminations Total Written Earned Written Earned Written Earned Written Earned Written Earned Written Earned Treaty reinsurance $ 1,118,532 $ 1,109,659 $ 149,079 $ 163,382 $ — $ — $ 126,785 $ 126,534 $ (53,457 ) $ (60,912 ) $ 1,340,939 $ 1,338,663 Facultative reinsurance — — 334,898 345,252 — — — — — — 334,898 345,252 Direct — — 617,793 576,136 65,235 80,838 — — — — 683,028 656,974 Ceded (163,678 ) (192,375 ) (192,211 ) (204,996 ) (6,428 ) (7,842 ) (4,348 ) (3,533 ) 53,457 60,912 (313,208 ) (347,834 ) Total $ 954,854 $ 917,284 $ 909,559 $ 879,774 $ 58,807 $ 72,996 $ 122,437 $ 123,001 $ — $ — $ 2,045,657 $ 1,993,055
Reinsurance recoverables by reinsurer	Reinsurance recoverables by reinsurer as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Reinsurance Recoverable % of Total Reinsurance Recoverable % of Total Top 10 reinsurers $ 395,308 84.9 % $ 303,108 81.1 % Other reinsurers’ balances > $1 million 66,944 14.4 % 61,222 16.4 % Other reinsurers’ balances < $1 million 3,416 0.7 % 9,327 2.5 % Total $ 465,668 100.0 % $ 373,657 100.0 % December 31, 2016 Top 10 Reinsurers Rating Reinsurance Recoverable % of Total Lloyd's Syndicates A+ $ 84,419 18.2 % Swiss Re AA- 84,044 18.1 % Fully collateralized reinsurers NR 83,088 17.8 % Hannover Re AA- 50,603 10.9 % Everest Re A+ 36,912 7.9 % Munich Re AA- 18,214 3.9 % Transatlantic Re A+ 10,593 2.3 % Hamilton Re A- 10,343 2.2 % Toa Re A+ 9,510 2.0 % National Indemnity Company AA+ 7,582 1.6 % Total $ 395,308 84.9 % NR: Not rated December 31, 2015 Top 10 Reinsurers Rating Reinsurance Recoverable % of Total Swiss Re AA- $ 83,048 22.2 % Lloyd's Syndicates A+ 66,356 17.8 % Hannover Re AA- 43,765 11.7 % Everest Re A+ 43,060 11.5 % Munich Re AA- 18,707 5.0 % Transatlantic Re A+ 11,923 3.2 % Hamilton Re A- 10,898 2.9 % National Indemnity Company AA+ 10,293 2.8 % XL Re A+ 8,728 2.3 % Toa Re A+ 6,330 1.7 % Total $ 303,108 81.1 %

Share capital (Tables)

Share capital (Tables)	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Note [Abstract]
Summary of preferred shares issued and outstanding	The following table is a summary of the Preferred shares issued and outstanding: Preferred Shares Preferred shares issued and outstanding, beginning of year — Preferred shares issued 6,000 Preferred shares issued and outstanding, end of year 6,000
Summary of common shares issued and outstanding	The following table is a summary of the common shares issued and outstanding during the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Common shares issued, beginning of year 160,570,772 155,554,224 154,488,497 Restricted share awards vested, net of shares withheld 612,100 614,945 615,659 Restricted share units vested, net of shares withheld 18,486 13,260 10,265 Options exercised 30,530 782,465 412,656 Warrants exercised — 3,593,715 — Direct issuance of common stock — 639 1,380 Performance shares vested, net of shares withheld 48,088 11,524 25,767 Common shares issued, end of year 161,279,976 160,570,772 155,554,224 Treasury shares, end of year (82,147,724 ) (77,670,155 ) (71,684,379 ) Common shares outstanding, end of year 79,132,252 82,900,617 83,869,845

Stock plans (Tables)

Stock plans (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options, activity during the period	Activity with respect to options for the year ended December 31, 2016 was as follows: Options Weighted Average Grant Date Fair Value Weighted Average Grant Date Exercise Price Total Intrinsic Value (a) Company Proceeds Received Options outstanding, beginning of year 65,401 $ 7.74 $ 20.17 Options exercised (39,265 ) 8.37 17.96 $ 1,260 $ 277 Options outstanding, end of year 26,136 $ 6.78 $ 23.48 Activity with respect to options for the year ended December 31, 2015 was as follows: Options Weighted Average Grant Date Fair Value Weighted Average Grant Date Exercise Price Total Intrinsic Value (a) Company Proceeds Received Options outstanding, beginning of year 1,160,057 $ 7.12 $ 17.74 Options exercised (1,094,656 ) 7.09 17.60 $ 26,367 $ 6,277 Options outstanding, end of year 65,401 $ 7.74 $ 20.17 Activity with respect to options for the year ended December 31, 2014 was as follows: Options Weighted Average Grant Date Fair Value Weighted Average Grant Date Exercise Price Total Intrinsic Value (a) Company Proceeds Received Options outstanding, beginning of year 1,572,713 $ 6.66 $ 18.88 Options exercised (412,656 ) 5.36 22.07 $ 7,459 $ 9,107 Options outstanding, end of year 1,160,057 $ 7.12 $ 17.74 (a) The total intrinsic value in the tables above represent the amount by which the market price of the Company’s common stock is greater than the option strike price multiplied by the number of options exercised during the year.
Restricted share awards, activity during the period	Activity with respect to unvested restricted share awards for the years ended December 31, 2016, 2015 and 2014 was as follows: Years Ended December 31, 2016 2015 2014 Restricted Share Awards Weighted Average Grant Date Fair Value Restricted Share Awards Weighted Average Grant Date Fair Value Restricted Share Awards Weighted Average Grant Date Fair Value Restricted share awards outstanding, beginning of year 2,739,446 $ 38.25 2,858,711 $ 35.81 2,684,745 $ 33.74 Restricted share awards granted 564,345 48.83 724,357 43.67 1,051,348 37.81 Restricted share awards vested (796,716 ) 37.40 (788,758 ) 34.41 (797,446 ) 31.44 Restricted share awards forfeited (37,093 ) 41.27 (54,864 ) 38.14 (79,936 ) 36.09 Restricted share awards outstanding, end of year 2,469,982 $ 40.89 2,739,446 $ 38.25 2,858,711 $ 35.81
Restricted share unit awards, activity during the period	Activity with respect to unvested restricted share units for the years ended December 31, 2016, 2015 and 2014 was as follows: Years Ended December 31, 2016 2015 2014 Restricted Share Units Weighted Average Grant Date Fair Value Restricted Share Units Weighted Average Grant Date Fair Value Restricted Share Units Weighted Average Grant Date Fair Value Restricted share units outstanding, beginning of year 114,337 $ 38.47 103,484 $ 36.54 66,518 $ 33.74 Restricted share units granted 27,609 50.03 28,057 42.91 53,025 38.10 Restricted share units vested (23,982 ) 38.18 (19,455 ) 34.58 (18,325 ) 30.71 Restricted share units issued in lieu of cash dividends 3,182 39.36 3,143 37.53 2,266 35.00 Restricted share units forfeited (8,338 ) 44.34 (892 ) 35.42 — — Restricted share units outstanding, end of year 112,808 $ 40.95 114,337 $ 38.47 103,484 $ 36.54
Performance share awards, activity during the period	Activity with respect to unvested performance share awards for the years ended December 31, 2016, 2015, and 2014 was as follows: Years Ended December 31, 2016 2015 2014 Performance Share Awards Weighted Average Grant Date Fair Value Performance Share Awards Weighted Average Grant Date Fair Value Performance Share Awards Weighted Average Grant Date Fair Value Performance share awards outstanding, beginning of year 172,594 $ 40.70 106,369 $ 36.03 101,820 $ 33.56 Performance share awards granted 125,290 48.75 81,569 45.03 52,639 37.33 Performance share awards vested (57,581 ) 36.11 (15,344 ) 31.38 (32,746 ) 32.62 Performance share awards conversion adjustment 45,517 36.82 — — (15,344 ) 31.38 Performance share awards outstanding, end of year 285,820 $ 44.53 172,594 $ 40.70 106,369 $ 36.03
Total share compensation expenses	The breakdown of share compensation expenses by award type is as follows: Years Ended December 31, 2016 2015 2014 Restricted share awards $ 36,887 $ 35,386 $ 31,335 Restricted share units 1,285 1,160 876 Performance share awards 4,735 1,795 862 Total $ 42,907 $ 38,341 $ 33,073

Retirement and pension plans (T

Retirement and pension plans (Tables)	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Summary of assumptions used to determine net periodic pension expense and benefit obligations	The assumptions used to determine net periodic pension expense for the years ended December 31, 2016 and 2015 are as follows: Years Ended December 31, 2016 2015 Discount rate 3.50 % 2.75 % Increase in compensation levels rate 5.00 % 5.00 % The assumptions used to determine benefit obligations as at December 31, 2016 and 2015 are as follows: December 31, 2016 December 31, 2015 Discount rate 4.00 % 4.00 % Increase in compensation levels rate 5.00 % 5.00 %
Analysis of the funded status and amounts recognized for defined benefit plans	The following tables present a reconciliation of the beginning and ending funded status and the net amounts recognized for the defined benefit plans for the years ended December 31, 2016 and 2015 : Years Ended December 31, 2016 2015 Change in benefit obligation Projected benefit obligation, beginning of year $ 15,722 $ 16,493 Service cost 1,026 1,024 Interest cost 594 434 Actuarial losses (gains) 1,473 (46 ) Benefit payments (98 ) (98 ) Settlements (1,738 ) (2,085 ) Projected benefit obligation, end of year $ 16,979 $ 15,722 Change in plan assets Fair value of plan assets, beginning of year $ — $ — Employer contributions 1,836 2,186 Benefit payments (98 ) (98 ) Settlements (1,738 ) (2,088 ) Fair value of plan assets, end of year — — Funded status at end of year $ (16,979 ) $ (15,722 ) Net amount recognized in accounts payable and accrued expenses $ (16,979 ) $ (15,722 ) Amounts recognized in accumulated other comprehensive loss consist of Net loss (gain) $ 226 $ (517 ) Prior service credit 6 4 Net amount recognized $ 232 $ (513 ) December 31, 2016 December 31, 2015 Projected benefit obligation $ 16,979 $ 15,722 Accumulated benefit obligation $ 13,480 $ 13,308 Fair value of plan assets $ — $ —
Components of net periodic pension expense	The components of net periodic pension expense for the years ended December 31, 2016 and 2015 are as follows: Years Ended December 31, 2016 2015 Service cost $ 1,026 $ 1,024 Interest cost 594 434 Amortization of prior service cost (2 ) (2 ) Amortization of net loss 374 312 Net periodic benefit cost 1,992 1,768 Settlement loss 356 484 Net periodic pension expense $ 2,348 $ 2,252
Summary of other changes in plan assets and benefit obligations recognized in other comprehensive income	Other changes in plan assets and benefit obligations recognized in other comprehensive loss for the years ended December 31, 2016 and 2015 are as follows: Years Ended December 31, 2016 2015 Net loss (gain) $ 1,473 $ (43 ) Amortization of loss (374 ) (312 ) Amortization of prior service cost 2 2 Settlement loss (356 ) (484 ) Total recognized in other comprehensive loss $ 745 $ (837 ) Total recognized in net pension expense and other comprehensive loss (before tax effects) $ 3,093 $ 1,415
Summary of expected benefit payments	As at December 31, 2016 , the projected benefits are as follows: December 31, 2016 2017 $ 2,740 2018 7,072 2019 92 2020 2,665 2021 83 2022-2026 5,449 Total benefit payments required $ 18,101

Debt and financing arrangemen57

Debt and financing arrangements (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule outstanding debentures and senior notes payable	The Company’s outstanding debentures and senior notes payable as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Deferrable debentures 2006 Junior Subordinated $ 150,000 $ 150,000 2007 Junior Subordinated 139,800 139,800 Flagstone 2006 Junior Subordinated 133,676 134,118 Flagstone 2007 Junior Subordinated 113,750 113,750 Total debentures payable 537,226 537,668 2010 Senior notes payable 250,000 250,000 Less: Unamortized debt issuance costs (4,638 ) (4,839 ) Total senior notes payable 245,362 245,161 Total debentures and senior notes payable $ 782,588 $ 782,829
Summary of outstanding credit and other facilities	The Company’s outstanding credit and other facilities as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Commitment Drawn and outstanding Commitment Drawn and outstanding Credit and other facilities $85,000 syndicated unsecured letter of credit facility $ 85,000 $ — $ 85,000 $ — $300,000 syndicated secured letter of credit facility 300,000 90,252 300,000 235,540 $24,000 secured bi-lateral letter of credit facility 24,000 4,553 24,000 10,543 $20,000 AlphaCat Re secured letter of credit facility 20,000 20,000 30,000 30,000 $25,000 IPC bi-lateral facility 25,000 5,842 25,000 9,241 $236,000 Flagstone bi-lateral facility 236,000 144,392 236,000 193,764 Total credit and other facilities $ 690,000 $ 265,039 $ 700,000 $ 479,088
Summary of key terms of debt instruments	The following table summarizes the key terms of the Company’s senior notes and junior subordinated deferrable debentures: Description Issuance date Amount Maturity date Interest Rate as at Interest payments due Issuance Date December 31, 2016 2006 Junior Subordinated Deferrable Debentures June 15, 2006 $ 150,000 June 15, 2036 9.069 % (a) 5.831 % (e) Quarterly Flagstone 2006 Junior Subordinated Deferrable Debentures August 23, 2006 $ 133,676 September 15, 2036 3.540 % (b) 6.463 % (e) Quarterly 2007 Junior Subordinated Deferrable Debentures June 21, 2007 $ 200,000 June 15, 2037 8.480 % (c) 5.180 % (e) Quarterly Flagstone 2007 Junior Subordinated Deferrable Debentures June 8, 2007 $ 88,750 July 30, 2037 3.000 % (b) 5.900 % (e) Quarterly Flagstone 2007 Junior Subordinated Deferrable Debentures September 20, 2007 $ 25,000 September 15, 2037 3.100 % (b) 5.983 % (e) Quarterly 2010 Senior Notes due 2040 January 26, 2010 $ 250,000 January 26, 2040 8.875 % (d) 8.875 % (d) Semi-annually in arrears (a) Fixed interest rate for 5 years , floating interest rate of three-month LIBOR plus 3.550% thereafter, reset quarterly. (b) Floating interest rate of three-month LIBOR plus amount stated, reset quarterly. (c) Fixed interest rate for 5 years , floating interest rate of three-month LIBOR plus 2.950% thereafter, reset quarterly. (d) Fixed interest rate. (e) Fixed interest rate as a result of interest rate swap contracts entered into by the Company.
Investments pledged as collateral under credit facilities	The Company has pledged investments and cash as collateral under the Company’s credit facilities in the total amount of $442,184 (December 31, 2015 : $826,535 ) as detailed in the table below: December 31, 2016 December 31, 2015 $300,000 syndicated secured letter of credit facility $ 157,597 $ 370,909 $24,000 secured bi-lateral letter of credit facility 48,097 47,607 $20,000 AlphaCat Re secured letter of credit facility 20,032 30,153 $236,000 Flagstone bi-lateral facility 216,458 377,866 Total $ 442,184 $ 826,535
Components of finance expenses	Finance expenses consist of interest on the junior subordinated deferrable debentures and senior notes, the amortization of debt offering costs, credit facility fees, bank charges, Talbot Funds at Lloyds (“FAL”) facility costs, AlphaCat financing fees and other charges as follows: Years Ended December 31, 2016 2015 2014 2006 Junior Subordinated Deferrable Debentures $ 8,893 $ 8,868 $ 8,868 2007 Junior Subordinated Deferrable Debentures 7,362 7,341 7,341 Flagstone 2006 Junior Subordinated Deferrable Debentures 9,028 8,989 9,001 Flagstone 2007 Junior Subordinated Deferrable Debentures 7,100 7,123 7,129 2010 Senior Notes due 2040 22,388 22,388 22,388 Credit facilities 2,060 6,006 5,516 Bank charges, Talbot FAL facility and other charges (a) 504 4,592 4,536 AlphaCat fees (b) 1,185 9,435 3,545 Total finance expenses $ 58,520 $ 74,742 $ 68,324 (a) On November 30, 2015, the Company terminated its Talbot FAL Facility provided and arranged by Lloyds Bank plc and ING Bank N.V., London Branch. (b) Includes finance expenses incurred by AlphaCat Managers in relation to fund raising for the AlphaCat sidecars, the AlphaCat ILS funds and AlphaCat direct.

Income taxes (Tables)

Income taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income before tax by jurisdiction	The Company’s income (loss) before income taxes for the years ended December 31, 2016 , 2015 and 2014 was generated in the following domestic and foreign jurisdictions: Years Ended December 31, 2016 2015 2014 Domestic Bermuda $ 447,257 $ 470,454 $ 518,476 Foreign U.K. 4,308 13,621 10,824 U.S. 4,038 (4,176 ) (11,752 ) Switzerland (1,084 ) 2,276 9,941 Canada 2,599 493 2,773 Other 33,736 (2,074 ) 29,076 Total income before income taxes $ 490,854 $ 480,594 $ 559,338
Components of income tax expense	Income tax (benefit) expense is comprised of both current and deferred tax attributable to U.S. and Non-U.S. jurisdictions as follows: Years Ended December 31, 2016 2015 2014 Current income tax expense U.S. $ 2,042 $ 739 $ 21,257 Non-U.S. 711 6,028 26,179 Total current income tax expense $ 2,753 $ 6,767 $ 47,436 Deferred income tax (benefit) expense U.S. $ (3,487 ) $ 1,360 $ (24,998 ) Non-U.S. (18,995 ) (1,751 ) (22,283 ) Total deferred income tax benefit $ (22,482 ) $ (391 ) $ (47,281 ) Total income tax (benefit) expense U.S. $ (1,445 ) $ 2,099 $ (3,741 ) Non-U.S. (18,284 ) 4,277 3,896 Total income tax (benefit) expense $ (19,729 ) $ 6,376 $ 155
Effective tax rate reconciliation	The table below is a reconciliation of the actual income tax (benefit) expense for the years ended December 31, 2016 , 2015 and 2014 to the amount computed by applying the effective tax rate of 0% under Bermuda law to income before taxes: Years Ended December 31, 2016 2015 2014 Expected tax expense at Bermuda statutory rate of 0% $ — $ — $ — Foreign tax rate differential 11,394 6,462 7,993 Changes in valuation allowance (36,990 ) 9,830 (7,284 ) Tax exempt income and expenses not deductible (1,960 ) 393 (6,055 ) Share compensation tax windfall 1,203 906 3,513 Impact of enacted changes in tax rates 8,931 69 250 Prior years tax adjustments (5,199 ) (12,272 ) 666 Other 2,892 988 1,072 Actual income tax (benefit) expense $ (19,729 ) $ 6,376 $ 155
Components of deferred tax assets and liabilities	Significant components of the Company’s deferred tax assets and liabilities as at December 31, 2016 and 2015 were as follows: December 31, 2016 December 31, 2015 Deferred tax asset Tax losses carried forward $ 116,416 $ 167,929 Deferred compensation 6,915 7,504 Deferred interest expense 2,039 2,047 Tax credits carried forward 5,469 2,761 Discounting of loss reserves 9,938 11,882 Unearned premiums reserve 6,647 4,291 Pension 5,943 5,503 Lloyd’s underwriting loss deductible in future periods 581 47 Other 4,943 4,111 Deferred tax asset, gross of valuation allowance 158,891 206,075 Valuation allowance (98,065 ) (167,929 ) Net deferred tax asset $ 60,826 $ 38,146 Deferred tax liability Deferred acquisition costs 4,633 1,989 Intangibles 7,583 8,111 Unrealized appreciation on investments 3,179 7,073 Properties and fixed assets 2,593 2,044 Other 2,640 1,115 Deferred tax liability 20,628 20,332 Net deferred tax asset $ 40,198 $ 17,814
Movement in deferred tax asset and related valuation allowance	The movement in deferred tax asset on tax losses carried forward and related valuation allowance from December 31, 2015 to December 31, 2016 can be explained as follows: Deferred Tax Asset on Tax Losses Carried Forward Valuation Allowance Balance as at December 31, 2015 $ 167,929 $ (167,929 ) Movement due to use of tax losses carried forward (10,990 ) 10,990 Movement due to provision to return adjustments 1,108 (1,108 ) Movement due to changes in enacted tax rates (8,757 ) 8,757 Movement due to change in assessment of deferred tax asset recoverability — 18,351 Forfeiture of tax losses carried forward (32,927 ) 32,927 Other 53 (53 ) Balance as at December 31, 2016 $ 116,416 $ (98,065 )
Net operating loss and capital loss carryforwards	As at December 31, 2016 , the Company had net operating and capital losses carried forward, inclusive of cumulative currency translation adjustments, as follows: Tax Jurisdiction Losses carried forward Tax effect Expiration U.S. $ 11,195 $ 3,918 2029 - 2035 Switzerland $ 157,512 $ 33,078 2018 - 2020 Luxembourg $ 300,121 $ 78,310 None Singapore $ 11,090 $ 1,109 None

Accumulated other comprehensi59

Accumulated other comprehensive loss (Tables)	12 Months Ended
	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Abstract]
Schedule of changes in AOCI	The changes in accumulated other comprehensive (loss) gain, by component for the years ended December 31, 2016 , 2015 and 2014 are as follows: Year Ended December 31, 2016 Foreign currency translation adjustment Minimum pension liability Cash flow hedge Total Balance, net of tax, beginning of year $ (11,834 ) $ 334 $ (1,069 ) $ (12,569 ) Other comprehensive (loss) gain, net of tax (10,440 ) (484 ) 277 (10,647 ) Balance, net of tax, end of year $ (22,274 ) $ (150 ) $ (792 ) $ (23,216 ) Year Ended December 31, 2015 Foreign currency translation adjustment Minimum pension liability Cash flow hedge Total Balance, net of tax, beginning of year $ (8,118 ) $ (210 ) $ (228 ) $ (8,556 ) Other comprehensive (loss) gain, net of tax (3,716 ) 544 (841 ) (4,013 ) Balance, net of tax, end of year $ (11,834 ) $ 334 $ (1,069 ) $ (12,569 ) Year Ended December 31, 2014 Foreign currency translation adjustment Minimum pension liability Cash flow hedge Total Balance, net of tax, beginning of year $ (617 ) $ — $ — $ (617 ) Other comprehensive loss, net of tax (7,501 ) (210 ) (228 ) (7,939 ) Balance, net of tax, end of year $ (8,118 ) $ (210 ) $ (228 ) $ (8,556 )

Commitments and contingencies (

Commitments and contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Percentage of gross premiums written by broker	The following table shows the percentage of gross premiums written by broker for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Marsh & McLennan Companies, Inc. 28.8 % 28.2 % 28.5 % Aon Benfield Group Ltd. 16.2 % 15.5 % 20.0 % Willis Towers Watson plc 14.1 % 14.3 % 18.0 %
Future minimum lease commitments	Future minimum lease commitments are as follows: December 31, 2016 2017 $ 11,878 2018 12,214 2019 11,958 2020 11,059 2021 10,316 2022 and thereafter 46,418 Total $ 103,843

Earnings per share (Tables)

Earnings per share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Computation of basic and diluted earnings per share	The following table sets forth the computation of basic earnings per share and earnings per diluted share available to common shareholders for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, 2016 2015 2014 Basic earnings per share Net income available to Validus common shareholders $ 359,384 $ 374,893 $ 479,963 Less: Dividends on outstanding warrants — (3,566 ) (6,208 ) Net income allocated to Validus common shareholders $ 359,384 $ 371,327 $ 473,755 Weighted average number of common shares outstanding 81,041,974 83,107,236 90,354,745 Basic earnings per share available to Validus common shareholders $ 4.43 $ 4.47 $ 5.24 Earnings per diluted share Net income available to Validus common shareholders $ 359,384 $ 374,893 $ 479,963 Less: Dividends on outstanding warrants — — — Net income allocated to Validus common shareholders $ 359,384 $ 374,893 $ 479,963 Weighted average number of common shares outstanding 81,041,974 83,107,236 90,354,745 Share equivalents: Warrants — 2,090,248 2,789,032 Stock options 28,196 151,867 745,561 Unvested restricted shares 1,289,290 1,077,409 800,933 Weighted average number of diluted common shares outstanding 82,359,460 86,426,760 94,690,271 Earnings per diluted share available to Validus common shareholders $ 4.36 $ 4.34 $ 5.07

Segment information (Tables)

Segment information (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Results of operating segments and corporate segment	The following tables summarize the results of our operating segments and “Corporate and Investments”: Years Ended December 31, Validus Re Segment Information 2016 2015 2014 Underwriting revenues Gross premiums written $ 1,111,054 $ 1,126,759 $ 1,118,532 Reinsurance premiums ceded (111,564 ) (149,088 ) (163,678 ) Net premiums written 999,490 977,671 954,854 Change in unearned premiums (55,545 ) 12,542 (37,570 ) Net premiums earned 943,945 990,213 917,284 Other insurance related (loss) income (55 ) 3,575 3,159 Total underwriting revenues 943,890 993,788 920,443 Underwriting deductions Losses and loss expenses 411,488 457,976 307,290 Policy acquisition costs 181,040 166,387 141,670 General and administrative expenses 72,770 78,428 74,739 Share compensation expenses 11,034 10,350 9,739 Total underwriting deductions 676,332 713,141 533,438 Underwriting income $ 267,558 $ 280,647 $ 387,005 Selected ratios: Ratio of net to gross premiums written 90.0 % 86.8 % 85.4 % Losses and loss expense ratio 43.6 % 46.2 % 33.5 % Policy acquisition cost ratio 19.2 % 16.8 % 15.5 % General and administrative expense ratio (a) 8.8 % 9.0 % 9.2 % Expense ratio 28.0 % 25.8 % 24.7 % Combined ratio 71.6 % 72.0 % 58.2 % (a) The general and administrative expense ratio includes share compensation expenses. Years Ended December 31, Talbot Segment Information 2016 2015 2014 Underwriting revenues Gross premiums written $ 970,702 $ 1,018,835 $ 1,101,770 Reinsurance premiums ceded (175,729 ) (198,896 ) (192,211 ) Net premiums written 794,973 819,939 909,559 Change in unearned premiums (13,057 ) 18,152 (29,785 ) Net premiums earned 781,916 838,091 879,774 Other insurance related income 455 851 1,095 Total underwriting revenues 782,371 838,942 880,869 Underwriting deductions Losses and loss expenses 424,946 347,322 423,394 Policy acquisition costs 177,127 187,535 187,162 General and administrative expenses 134,479 155,306 150,828 Share compensation expenses 13,078 12,373 11,346 Total underwriting deductions 749,630 702,536 772,730 Underwriting income $ 32,741 $ 136,406 $ 108,139 Selected ratios: Ratio of net to gross premiums written 81.9 % 80.5 % 82.6 % Losses and loss expense ratio 54.3 % 41.4 % 48.1 % Policy acquisition cost ratio 22.7 % 22.4 % 21.3 % General and administrative expense ratio (a) 18.9 % 20.0 % 18.4 % Expense ratio 41.6 % 42.4 % 39.7 % Combined ratio 95.9 % 83.8 % 87.8 % (a) The general and administrative expense ratio includes share compensation expenses. Years Ended December 31, Western World Segment Information 2016 2015 2014 (a) Underwriting revenues Gross premiums written $ 323,220 $ 278,504 $ 65,235 Reinsurance premiums ceded (22,634 ) (18,877 ) (6,428 ) Net premiums written 300,586 259,627 58,807 Change in unearned premiums (27,354 ) (977 ) 14,189 Net premiums earned 273,232 258,650 72,996 Other insurance related income 912 1,044 264 Total underwriting revenues 274,144 259,694 73,260 Underwriting deductions Losses and loss expenses 183,812 171,878 51,035 Policy acquisition costs 64,442 41,408 3,169 General and administrative expenses 43,280 38,715 11,121 Share compensation expenses 2,543 2,083 135 Total underwriting deductions 294,077 254,084 65,460 Underwriting (loss) income $ (19,933 ) $ 5,610 $ 7,800 Selected ratios: Ratio of net to gross premiums written 93.0 % 93.2 % 90.1 % Losses and loss expense ratio 67.3 % 66.4 % 69.9 % Policy acquisition cost ratio 23.5 % 16.0 % 4.4 % General and administrative expense ratio (b) 16.8 % 15.8 % 15.4 % Expense ratio 40.3 % 31.8 % 19.8 % Combined ratio 107.6 % 98.2 % 89.7 % (a) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition. (b) The general and administrative expense ratio includes share compensation expenses. Years Ended December 31, AlphaCat Segment Information (a) 2016 2015 2014 Revenues Third party $ 18,771 $ 19,661 $ 18,667 Related party 3,329 5,309 7,467 Total revenues 22,100 24,970 26,134 Expenses General and administrative expenses 10,233 12,115 10,134 Share compensation expenses 249 580 501 Finance expenses 947 9,312 3,417 Tax expenses 90 — — Foreign exchange losses (gains) 19 (16 ) (20 ) Total expenses 11,538 21,991 14,032 Income before investment income from AlphaCat Funds and Sidecars 10,562 2,979 12,102 Investment income (loss) from AlphaCat Funds and Sidecars (b) AlphaCat Re & Master Fund — — (1,377 ) AlphaCat Sidecars 607 5,504 10,525 AlphaCat ILS Funds - Lower Risk 8,901 7,491 7,974 AlphaCat ILS Funds - Higher Risk 7,471 8,428 8,754 BetaCat ILS Funds 3,623 1,702 (51 ) PaCRe (23 ) (3,949 ) (4,340 ) Total investment income from AlphaCat Funds and Sidecars 20,579 19,176 21,485 Validus’ share of AlphaCat income $ 31,141 $ 22,155 $ 33,587 Supplemental information: Gross premiums written AlphaCat Sidecars $ (341 ) $ 45,755 $ 50,023 AlphaCat ILS Funds - Lower Risk 112,222 91,363 52,264 AlphaCat ILS Funds - Higher Risk 140,022 34,228 24,498 AlphaCat Direct (c) 18,499 4,780 — Total gross premiums written $ 270,402 $ 176,126 $ 126,785 (a) The results of AlphaCat are presented on an asset manager basis, which is non-GAAP. A reconciliation of Validus’ share of AlphaCat segment income to segmental income is presented in the tables below. (b) The investment income from the AlphaCat funds and sidecars is based on equity accounting. (c) AlphaCat Direct includes direct investments from third party investors in AlphaCat Re. Years Ended December 31, Corporate and Investments 2016 2015 2014 Investment income Managed net investment income (a) $ 141,718 $ 121,166 $ 95,800 Operating expenses General and administrative expenses 72,249 75,724 80,210 Share compensation expenses 16,003 12,955 11,352 Finance expenses (a) 57,183 61,071 60,309 Dividends on preferred shares 4,455 — — Tax (benefit) expense (a) (19,819 ) 6,376 155 Total operating expenses 130,071 156,126 152,026 Other items Net realized gains on managed investments (a) 14,680 1,698 12,160 Change in net unrealized gains (losses) on managed investments (a) 14,106 (32,007 ) (1,030 ) (Loss) income from investment affiliates (2,083 ) 4,281 8,411 Foreign exchange gains (losses) (a) 10,778 (8,172 ) (10,700 ) Other loss (766 ) (1,002 ) (2,243 ) Transaction expenses (b) — — (8,096 ) Total other items 36,715 (35,202 ) (1,498 ) Total Corporate and Investments $ 48,362 $ (70,162 ) $ (57,724 ) (a) These items exclude the components which are included in Validus’ share of AlphaCat and amounts which are consolidated from VIEs. (b) The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services. The following tables reconcile the results of our operating segments and “Corporate & Investments” to the Consolidated results of the Company for the years indicated: Year Ended December 31, 2016 Validus Re Segment Talbot Segment Western World Segment AlphaCat Segment and Consolidated VIEs Corporate and Investments Eliminations Total Underwriting revenues Gross premiums written $ 1,111,054 $ 970,702 $ 323,220 $ 270,402 $ — $ (26,673 ) $ 2,648,705 Reinsurance premiums ceded (111,564 ) (175,729 ) (22,634 ) (6,451 ) — 26,673 (289,705 ) Net premiums written 999,490 794,973 300,586 263,951 — — 2,359,000 Change in unearned premiums (55,545 ) (13,057 ) (27,354 ) (13,879 ) — — (109,835 ) Net premiums earned 943,945 781,916 273,232 250,072 — — 2,249,165 Other insurance related (loss) (55 ) 455 912 22,386 — (20,737 ) 2,961 Total underwriting revenues 943,890 782,371 274,144 272,458 — (20,737 ) 2,252,126 Underwriting deductions Losses and loss expenses 411,488 424,946 183,812 44,851 — — 1,065,097 Policy acquisition costs 181,040 177,127 64,442 26,905 — (32 ) 449,482 General and administrative expenses 72,770 134,479 43,280 34,333 72,249 (20,817 ) 336,294 Share compensation expenses 11,034 13,078 2,543 249 16,003 — 42,907 Total underwriting deductions 676,332 749,630 294,077 106,338 88,252 (20,849 ) 1,893,780 Underwriting income (loss) $ 267,558 $ 32,741 $ (19,933 ) $ 166,120 $ (88,252 ) $ 112 $ 358,346 Other items (a) — — — 2,478 (649 ) — 1,829 Dividends on preferred shares — — — — (4,455 ) — (4,455 ) Net investment income — — — 9,264 141,718 (597 ) 150,385 (Income) attributable to AlphaCat investors — — — (23,358 ) — — (23,358 ) Net (income) attributable to noncontrolling interests — — — (123,363 ) — — (123,363 ) Segmental income (loss) $ 267,558 $ 32,741 $ (19,933 ) $ 31,141 $ 48,362 $ (485 ) Net income available to Validus common shareholders $ 359,384 (a) Other items includes finance expenses, tax (benefit) expense, foreign exchange gains (losses), net realized and change in net unrealized gains (losses) on investments, income from investment and operating affiliates and other income (loss). Year Ended December 31, 2015 Validus Re Segment Talbot Segment Western World Segment AlphaCat Segment and Consolidated VIEs Corporate and Investments Eliminations Total Underwriting revenues Gross premiums written $ 1,126,759 $ 1,018,835 $ 278,504 $ 176,126 $ — $ (42,718 ) $ 2,557,506 Reinsurance premiums ceded (149,088 ) (198,896 ) (18,877 ) (4,538 ) — 42,718 (328,681 ) Net premiums written 977,671 819,939 259,627 171,588 — — 2,228,825 Change in unearned premiums 12,542 18,152 (977 ) (11,653 ) — — 18,064 Net premiums earned 990,213 838,091 258,650 159,935 — — 2,246,889 Other insurance related income 3,575 851 1,044 25,524 — (24,881 ) 6,113 Total underwriting revenues 993,788 838,942 259,694 185,459 — (24,881 ) 2,253,002 Underwriting deductions Losses and loss expenses 457,976 347,322 171,878 657 — — 977,833 Policy acquisition costs 166,387 187,535 41,408 16,327 — (1,599 ) 410,058 General and administrative expenses 78,428 155,306 38,715 39,055 75,724 (23,519 ) 363,709 Share compensation expenses 10,350 12,373 2,083 580 12,955 — 38,341 Total underwriting deductions 713,141 702,536 254,084 56,619 88,679 (25,118 ) 1,789,941 Underwriting income $ 280,647 $ 136,406 $ 5,610 $ 128,840 $ (88,679 ) $ 237 $ 463,061 Other items (a) — — — (17,967 ) (102,649 ) — (120,616 ) Dividends on preferred shares — — — — — — — Net investment income — — — 6,658 121,166 — 127,824 (Income) attributable to AlphaCat investors — — — (2,412 ) — — (2,412 ) Net (income) attributable to noncontrolling interests — — — (92,964 ) — — (92,964 ) Segmental income $ 280,647 $ 136,406 $ 5,610 $ 22,155 $ (70,162 ) $ 237 Net income available to Validus $ 374,893 (a) Other items includes finance expenses, tax expenses, foreign exchange gains (losses), net realized and change in net unrealized gains (losses) on investments, income from investment and operating affiliates and other income (loss). Year Ended December 31, 2014 Validus Re Segment Talbot Segment Western World Segment (c) AlphaCat Segment and Consolidated VIEs Corporate and Investments Eliminations Total Underwriting revenues Gross premiums written $ 1,118,532 $ 1,101,770 $ 65,235 $ 126,785 $ — $ (53,457 ) $ 2,358,865 Reinsurance premiums ceded (163,678 ) (192,211 ) (6,428 ) (4,348 ) — 53,457 (313,208 ) Net premiums written 954,854 909,559 58,807 122,437 — — 2,045,657 Change in unearned premiums (37,570 ) (29,785 ) 14,189 564 — — (52,602 ) Net premiums earned 917,284 879,774 72,996 123,001 — — 1,993,055 Other insurance related income 3,159 1,095 264 25,750 — (26,796 ) 3,472 Total underwriting revenues 920,443 880,869 73,260 148,751 — (26,796 ) 1,996,527 Underwriting deductions Losses and loss expenses 307,290 423,394 51,035 (16,704 ) — — 765,015 Policy acquisition costs 141,670 187,162 3,169 11,584 — (4,118 ) 339,467 General and administrative expenses 74,739 150,828 11,121 36,298 80,210 (23,834 ) 329,362 Share compensation expenses 9,739 11,346 135 501 11,352 — 33,073 Total underwriting deductions 533,438 772,730 65,460 31,679 91,562 (27,952 ) 1,466,917 Underwriting income $ 387,005 $ 108,139 $ 7,800 $ 117,072 $ (91,562 ) $ 1,156 $ 529,610 Other items (a) — — — (12,891 ) (53,866 ) — (66,757 ) Net investment income — — — 4,286 95,800 — 100,086 Net (income) attributable to noncontrolling interests — — — (74,880 ) — — (74,880 ) Transaction expenses (b) — — — — (8,096 ) — (8,096 ) Segmental income $ 387,005 $ 108,139 $ 7,800 $ 33,587 $ (57,724 ) $ 1,156 Net income available to Validus $ 479,963 (a) Other items includes finance expenses, tax expenses, foreign exchange gains (losses), net realized and change in net unrealized gains (losses) on investments, income from investment and operating affiliates and other income (loss). (b) The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services. (c) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.
Gross premiums written by line of business	The following table sets forth the gross premiums written by line of business for the years indicated: Years Ended December 31, 2016 2015 2014 (a) Property $ 1,128,523 $ 1,077,700 $ 1,050,109 Marine 363,656 471,857 576,478 Specialty 927,746 782,463 677,026 Liability 228,780 225,486 55,252 Total $ 2,648,705 $ 2,557,506 $ 2,358,865 (a) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.
Gross premiums written allocated to the territory of coverage exposure	The following tables set forth the gross premiums written allocated to the territory of coverage exposure for the years indicated: Gross Premiums Written Year Ended December 31, 2016 Validus Re Talbot Western World AlphaCat Eliminations Total % United States $ 448,243 $ 103,415 $ 323,220 $ 64,766 $ (2,057 ) $ 937,587 35.4 % Worldwide excluding United States (a) 51,902 148,347 — 22,206 (689 ) 221,766 8.4 % Australia and New Zealand 7,389 10,844 — 4,949 (133 ) 23,049 0.9 % Europe 28,967 34,264 — 3,245 (695 ) 65,781 2.4 % Latin America and Caribbean 47,586 102,293 — — (9,484 ) 140,395 5.3 % Japan 40,099 6,580 — 3,221 (33 ) 49,867 1.9 % Canada 3,349 6,834 — 207 (147 ) 10,243 0.4 % Rest of the world (b) 22,595 107,106 — — (2,449 ) 127,252 4.8 % Sub-total, non United States 201,887 416,268 — 33,828 (13,630 ) 638,353 24.1 % Worldwide including United States (a) 167,065 98,311 — 170,253 (10,983 ) 424,646 16.0 % Other locations non-specific (c) 293,859 352,708 — 1,555 (3 ) 648,119 24.5 % Total $ 1,111,054 $ 970,702 $ 323,220 $ 270,402 $ (26,673 ) $ 2,648,705 100.0 % Gross Premiums Written Year Ended December 31, 2015 Validus Re Talbot Western World AlphaCat Eliminations Total % United States $ 530,541 $ 106,679 $ 278,504 $ 41,134 $ (2,547 ) $ 954,311 37.4 % Worldwide excluding United States (a) 52,860 127,540 — 8,107 (1,186 ) 187,321 7.3 % Australia and New Zealand 12,190 8,974 — 624 (244 ) 21,544 0.8 % Europe 48,240 38,657 — 2,504 (1,135 ) 88,266 3.5 % Latin America and Caribbean 46,258 103,318 — 38 (15,481 ) 134,133 5.2 % Japan 38,885 5,171 — 1,671 (109 ) 45,618 1.8 % Canada 3,129 6,666 — 458 (231 ) 10,022 0.4 % Rest of the world (b) 21,498 103,237 — — (3,660 ) 121,075 4.7 % Sub-total, non United States 223,060 393,563 — 13,402 (22,046 ) 607,979 23.7 % Worldwide including United States (a) 139,419 100,523 — 116,523 (18,120 ) 338,345 13.2 % Other locations non-specific (c) 233,739 418,070 — 5,067 (5 ) 656,871 25.7 % Total $ 1,126,759 $ 1,018,835 $ 278,504 $ 176,126 $ (42,718 ) $ 2,557,506 100.0 % Gross Premiums Written Year Ended December 31, 2014 Validus Re Talbot Western World (d) AlphaCat Eliminations Total % United States $ 437,124 $ 108,458 $ 65,235 $ 26,067 $ (3,664 ) $ 633,220 26.8 % Worldwide excluding United States (a) 76,370 139,570 — 6,727 (1,575 ) 221,092 9.4 % Australia and New Zealand 20,617 9,736 — 1,019 (360 ) 31,012 1.3 % Europe 57,223 45,615 — 2,305 (1,292 ) 103,851 4.4 % Latin America and Caribbean 56,102 116,281 — — (26,007 ) 146,376 6.2 % Japan 42,813 4,116 — 608 (111 ) 47,426 2.0 % Canada 3,793 10,194 — 214 (337 ) 13,864 0.6 % Rest of the world (b) 25,272 93,012 — — (3,805 ) 114,479 4.9 % Sub-total, non United States 282,190 418,524 — 10,873 (33,487 ) 678,100 28.8 % Worldwide including United States (a) 175,098 96,187 — 89,845 (16,196 ) 344,934 14.6 % Other locations non-specific (c) 224,120 478,601 — — (110 ) 702,611 29.8 % Total $ 1,118,532 $ 1,101,770 $ 65,235 $ 126,785 $ (53,457 ) $ 2,358,865 100.0 % (a) Represents risks in two or more geographic zones. (b) Represents risks in one geographic zone. (c) The other locations non-specific category refers to business for which an analysis of exposure by geographic zone is not applicable since these exposures can span multiple geographic areas and, in some instances, are not fixed locations. (d) The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.

Statutory and regulatory requ63

Statutory and regulatory requirements (Tables)	12 Months Ended
	Dec. 31, 2016
Statutory and regulatory requirements [Abstract]
Statutory amounts based on regulatory requirements	Statutory capital and surplus as at December 31, 2016 and 2015 and statutory net income for the years ended December 31, 2016 , 2015 and 2014 for our (re)insurance subsidiaries based in our most significant regulatory jurisdictions were as follows: Statutory Capital and Surplus Required Actual Statutory Net Income December 31, December 31, Years Ended December 31, 2016 2015 2016 2015 2016 2015 2014 Bermuda $ 734,045 $ 1,463,408 $ 3,712,369 $ 3,469,849 $ 369,684 $ 329,260 $ 511,652 United States 78,342 80,047 416,746 421,047 7,795 32,255 105,210 Switzerland 267,000 259,000 806,099 750,356 46,362 21,379 44,939

Condensed unaudited quarterly64

Condensed unaudited quarterly financial information (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Schedule Of Condensed Quarterly Financial Information [Table Text Block]	Quarters Ended December 31, 2016 September 30, 2016 June 30, March 31, Unaudited Unaudited Unaudited Unaudited Revenues Gross premiums written $ 339,454 $ 372,418 $ 764,042 $ 1,172,791 Reinsurance premiums ceded (40,635 ) (45,006 ) (36,229 ) (167,835 ) Net premiums written 298,819 327,412 727,813 1,004,956 Change in unearned premiums 241,580 236,363 (154,090 ) (433,688 ) Net premiums earned 540,399 563,775 573,723 571,268 Net investment income 38,153 43,514 39,257 29,461 Net realized gains (losses) on investments 9,220 4,397 2,724 (584 ) Change in net unrealized (losses) gains on investments (67,460 ) 5,459 31,428 47,444 Income (loss) from investment affiliates 2,166 453 (589 ) (4,113 ) Other insurance related income (loss) and other income 568 (610 ) 824 1,413 Foreign exchange (losses) gains (901 ) (766 ) 6,286 6,245 Total revenues 522,145 616,222 653,653 651,134 Expenses Losses and loss expenses 275,126 258,394 307,130 224,447 Policy acquisition costs 120,889 113,434 107,966 107,193 General and administrative expenses 77,955 82,443 89,688 86,208 Share compensation expenses 10,442 10,501 10,727 11,237 Finance expenses 14,630 14,521 14,166 15,203 Total expenses 499,042 479,293 529,677 444,288 Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors 23,103 136,929 123,976 206,846 Tax benefit (expense) 21,147 (1,830 ) (1,706 ) 2,118 Loss from operating affiliate — — — (23 ) (Income) attributable to AlphaCat investors (7,080 ) (5,564 ) (6,114 ) (4,600 ) Net income $ 37,170 $ 129,535 $ 116,156 $ 204,341 Net (income) attributable to noncontrolling interests (27,200 ) (37,439 ) (21,193 ) (37,531 ) Net income available to Validus 9,970 92,096 94,963 166,810 Dividends on preferred shares (2,203 ) (2,252 ) — — Net income available to Validus common shareholders $ 7,767 $ 89,844 $ 94,963 $ 166,810 Earnings per share Basic earnings per share available to Validus common shareholders $ 0.10 $ 1.12 $ 1.16 $ 2.01 Earnings per diluted share available to Validus common shareholders $ 0.10 $ 1.11 $ 1.14 $ 1.98 Cash dividends declared per common share $ 0.35 $ 0.35 $ 0.35 $ 0.35 Quarters Ended December 31, 2015 September 30, 2015 June 30, March 31, Unaudited Unaudited Unaudited Unaudited Revenues Gross premiums written $ 309,605 $ 402,509 $ 726,168 $ 1,119,224 Reinsurance premiums ceded (33,128 ) (48,810 ) (55,418 ) (191,325 ) Net premiums written 276,477 353,699 670,750 927,899 Change in unearned premiums 266,823 201,312 (98,062 ) (352,009 ) Net premiums earned 543,300 555,011 572,688 575,890 Net investment income 31,612 31,572 33,611 31,029 Net realized (losses) gains on investments (2,928 ) (1,187 ) 2,244 4,169 Change in net unrealized (losses) gains on investments (34,862 ) 3,916 (34,676 ) 33,227 (Loss) income from investment affiliates (1,261 ) 2,482 284 2,776 Other insurance related income and other income 2,545 1,526 100 940 Foreign exchange gains (losses) 797 (2,592 ) (2,671 ) (4,265 ) Total revenues 539,203 590,728 571,580 643,766 Expenses Losses and loss expenses 214,748 256,010 266,146 240,929 Policy acquisition costs 102,285 105,039 104,323 98,411 General and administrative expenses 98,563 96,886 84,025 84,235 Share compensation expenses 10,062 9,983 9,242 9,054 Finance expenses 16,581 18,512 18,682 20,967 Total expenses 442,239 486,430 482,418 453,596 Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors 96,964 104,298 89,162 190,170 Tax benefit (expense) 756 (2,018 ) (2,549 ) (2,565 ) (Loss) income from operating affiliate (1,708 ) (7,963 ) 1,738 3,984 (Income) attributable to AlphaCat investors (974 ) (1,438 ) — — Net income $ 95,038 $ 92,879 $ 88,351 $ 191,589 Net (income) attributable to noncontrolling interests (25,996 ) (26,229 ) (22,561 ) (18,178 ) Net income available to Validus 69,042 66,650 65,790 173,411 Dividends on preferred shares — — — — Net income available to Validus common shareholders $ 69,042 $ 66,650 $ 65,790 $ 173,411 Earnings per share Basic earnings per share available to Validus common shareholders $ 0.84 $ 0.79 $ 0.77 $ 2.07 Earnings per diluted share available to Validus common shareholders $ 0.81 $ 0.78 $ 0.75 $ 1.98 Cash dividends declared per common share $ 0.32 $ 0.32 $ 0.32 $ 0.32

Nature of the business (Details

Nature of the business (Details)	12 Months Ended
	Dec. 31, 2016segments
Nature Of Business [Abstract]
Number of operating segments	4

Significant accounting polici66

Significant accounting policies (Details)	12 Months Ended
	Dec. 31, 2016
Premiums
Significant Accounting Policies [Line Items]
Assumed risk period, in months	24 months
Derivative | Maximum
Significant Accounting Policies [Line Items]
Hedge effectiveness criteria, percent	125.00%
Derivative | Minimum
Significant Accounting Policies [Line Items]
Hedge effectiveness criteria, percent	80.00%
Cash and cash equivalents
Significant Accounting Policies [Line Items]
Time period for recognition, as shown	1 month

Business combination (Acquisiti

Business combination (Acquisition details) (Details) - USD ($) $ in Thousands	Oct. 02, 2014	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2014
Liabilities acquired
Goodwill		$ 196,758	$ 196,758	$ 195,897
Western World Insurance Group, Inc
Total allocable purchase price
Total allocable purchase price	$ 692,305
Tangible assets acquired
Cash and cash equivalents	48,760
Investments	1,126,185
Receivables	37,848
Other assets	19,418
Tangible assets acquired	1,232,211
Intangible assets acquired
Intangible assets acquired	25,055
Liabilities acquired
Net loss reserves and paid losses recoverable	523,315
Unearned premiums, net of expenses	135,686
Other liabilities	81,464
Liabilities acquired	740,465
Goodwill		176,365		$ 175,504
Measurement period adjustments to assets		$ 861
Western World Insurance Group, Inc | Brand names
Intangible assets acquired
Intangible asset - finite-lived	5,756
Western World Insurance Group, Inc | Distribution network
Intangible assets acquired
Intangible asset - finite-lived	4,651
Western World Insurance Group, Inc | Technology
Intangible assets acquired
Intangible asset - finite-lived	2,323
Western World Insurance Group, Inc | State licenses
Intangible assets acquired
Intangible asset - indefinite-lived	$ 12,325

Business combination (Pro forma

Business combination (Pro forma information) (Details) - Western World Insurance Group, Inc $ in Thousands	12 Months Ended
	Dec. 31, 2014USD ($)
Business Acquisition [Line Items]
Net premiums earned	$ 2,216,349
Net operating income	481,179
Net income	$ 448,071

Business combination (Results s

Business combination (Results since acquisition) (Details) - Western World Insurance Group, Inc $ in Thousands	3 Months Ended
	Dec. 31, 2014USD ($)
Business Acquisition [Line Items]
Net premiums written	$ 58,807
Total revenue	78,325
Total expenses	(66,882)
Net income	$ 11,443

Goodwill and other intangible70

Goodwill and other intangible assets (Analysis of goodwill and intangible assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill, beginning of year	$ 196,758	$ 195,897
Measurement period adjustments		861
Goodwill, end of year	196,758	196,758	$ 195,897
Finite lived intangible assets, beginning of year	17,090	22,756
Finite lived intangible assets, end of year	11,424	17,090	22,756
Indefinite-lived intangible assets, beginning of year	104,168	104,168
Indefinite-lived intangible assets, end of year	104,168	104,168	104,168
Total intangible assets, beginning of year	121,258	126,924
Amortization of intangible assets	(5,666)	(5,666)	(4,538)
Total intangible assets, end of year	115,592	121,258	126,924
Talbot
Goodwill [Line Items]
Goodwill, beginning of year	20,393	20,393
Measurement period adjustments		0
Goodwill, end of year	20,393	20,393	20,393
Western World Insurance Group, Inc
Goodwill [Line Items]
Goodwill, beginning of year	176,365	175,504
Measurement period adjustments		861
Goodwill, end of year	$ 176,365	$ 176,365	$ 175,504

Goodwill and other intangible71

Goodwill and other intangible assets (Analysis of carrying value and accumulated amortization of intangible assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	$ 60,343	$ 60,343
Finite-lived intangible assets, accumulated amortization	(48,919)	(43,253)
Finite-lived intangible assets, net carrying amount	11,424	17,090	$ 22,756
Indefinite-lived intangible assets, gross and net carrying amount	104,168	104,168	$ 104,168
Syndicate capacity
Goodwill And Other Intangible Assets [Line Items]
Indefinite-lived intangible assets, gross and net carrying amount	91,843	91,843
State licenses
Goodwill And Other Intangible Assets [Line Items]
Indefinite-lived intangible assets, gross and net carrying amount	12,325	12,325
Trade name and customer relationships
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	18,189	18,189
Finite-lived intangible assets, accumulated amortization	(13,406)	(12,187)
Finite-lived intangible assets, net carrying amount	4,783	6,002
Distribution network
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	39,831	39,831
Finite-lived intangible assets, accumulated amortization	(34,468)	(30,485)
Finite-lived intangible assets, net carrying amount	5,363	9,346
Technology
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	2,323	2,323
Finite-lived intangible assets, accumulated amortization	(1,045)	(581)
Finite-lived intangible assets, net carrying amount	$ 1,278	$ 1,742

Goodwill and other intangible72

Goodwill and other intangible assets (Remaining amortization expense) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
2,017	$ 3,585
2,018	1,505
2,019	1,389
2,020	1,041
2,021	1,041
2022 and thereafter	2,863
Intangible assets with a finite life, net	$ 11,424	$ 17,090	$ 22,756

Goodwill and other intangible73

Goodwill and other intangible assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 196,758	$ 196,758	$ 195,897
Measurement period adjustments		861
Amortization of intangible assets	5,666	5,666	4,538
Western World Insurance Group, Inc
Business Acquisition [Line Items]
Goodwill	$ 176,365	176,365	$ 175,504
Measurement period adjustments		$ 861
Minimum
Business Acquisition [Line Items]
Useful lives of acquired intangible assets	5 years
Maximum
Business Acquisition [Line Items]
Useful lives of acquired intangible assets	10 years

Investments (Amortized cost or

Investments (Amortized cost or cost and fair value of investments) (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		$ 5,584,599	$ 5,556,900
Short-term investments, at amortized cost		2,796,358	1,941,615
Other investments, at amortized cost		380,130	315,963
Investments in investment affiliates, at cost		84,840	69,794
Total investments, amortized cost		8,845,927	7,884,272
Fixed maturities, at fair value		5,543,030	5,510,331
Short-term investments, at fair value		2,796,170	1,941,635
Other investments, at fair value		405,712	336,856
Investments in investment affiliates		100,431	87,673
Total investments, at fair value		8,845,343	7,876,495
Managed investments
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		5,427,113	5,369,053
Short-term investments, at amortized cost		228,574	237,349
Other investments, at amortized cost		380,130	315,963
Investments in investment affiliates, at cost	[1]	84,840	69,794
Total investments, amortized cost		6,120,657	5,992,159
Fixed maturities, at fair value		5,384,699	5,323,952
Short-term investments, at fair value		228,386	237,369
Other investments, at fair value		405,712	336,856
Investments in investment affiliates	[1]	100,431	87,673
Total investments, at fair value		6,119,228	5,985,850
Managed investments | U.S. government and government agency
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		809,392	940,428
Fixed maturities, at fair value		804,126	937,202
Managed investments | Non-U.S. government and government agency
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		245,651	241,549
Fixed maturities, at fair value		240,791	237,968
Managed investments | U.S. states, municipalities and political subdivisions
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		271,742	299,929
Fixed maturities, at fair value		271,830	301,289
Managed investments | Agency residential mortgage-backed securities
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		684,490	606,676
Fixed maturities, at fair value		679,595	610,582
Managed investments | Non-agency residential mortgage-backed securities
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		15,858	27,025
Fixed maturities, at fair value		15,477	26,920
Managed investments | U.S. corporate
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		1,540,036	1,503,614
Fixed maturities, at fair value		1,534,508	1,489,951
Managed investments | Non-U.S. corporate
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		418,520	453,178
Fixed maturities, at fair value		410,227	446,570
Managed investments | Bank loans
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		579,121	592,981
Fixed maturities, at fair value		570,399	576,211
Managed investments | Asset-backed securities
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		528,563	440,363
Fixed maturities, at fair value		526,814	437,124
Managed investments | Commercial mortgage backed securities
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		333,740	263,310
Fixed maturities, at fair value		330,932	260,135
Managed investments | Fund of hedge funds
Amortized cost or cost and fair value of investments
Other investments, at amortized cost		1,457	1,457
Other investments, at fair value		955	1,417
Managed investments | Hedge funds
Amortized cost or cost and fair value of investments
Other investments, at amortized cost		11,292	14,018
Other investments, at fair value		17,381	20,980
Managed investments | Private equity investments
Amortized cost or cost and fair value of investments
Other investments, at amortized cost		72,814	53,489
Other investments, at fair value		89,809	63,771
Managed investments | Fixed income investment funds
Amortized cost or cost and fair value of investments
Other investments, at amortized cost		241,536	188,121
Other investments, at fair value		242,093	188,721
Managed investments | Overseas deposits
Amortized cost or cost and fair value of investments
Other investments, at amortized cost		50,106	54,484
Other investments, at fair value		50,106	54,484
Managed investments | Mutual funds
Amortized cost or cost and fair value of investments
Other investments, at amortized cost		2,925	4,394
Other investments, at fair value		5,368	7,483
Non-managed investments
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		157,486	187,847
Short-term investments, at amortized cost		2,567,784	1,704,266
Total investments, amortized cost		2,725,270	1,892,113
Fixed maturities, at fair value		158,331	186,379
Short-term investments, at fair value		2,567,784	1,704,266
Total investments, at fair value		2,726,115	1,890,645
Non-managed investments | Catastrophe bonds
Amortized cost or cost and fair value of investments
Fixed maturities, at amortized cost		157,486	187,847
Fixed maturities, at fair value		$ 158,331	$ 186,379
[1]	The Company’s investments in investment affiliates have been treated as equity method investments with the corresponding gains and losses recorded inincome as “Income (loss) from investment affiliates.”

Investments (Fixed maturities b

Investments (Fixed maturities by investment rating) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fixed Maturities
Estimated fair value	$ 5,543,030	$ 5,510,331
Percentage of total	100.00%	100.00%
Managed investments
Fixed Maturities
Estimated fair value	$ 5,384,699	$ 5,323,952
Percentage of total	97.10%	96.60%
Managed investments | Investment Grade
Fixed Maturities
Estimated fair value	$ 4,766,696	$ 4,659,892
Percentage of total	86.00%	84.60%
Managed investments | Investment Grade | AAA [Member]
Fixed Maturities
Estimated fair value	$ 2,405,597	$ 2,367,642
Percentage of total	43.40%	43.00%
Managed investments | Investment Grade | AA [Member]
Fixed Maturities
Estimated fair value	$ 538,289	$ 569,386
Percentage of total	9.70%	10.30%
Managed investments | Investment Grade | A [Member]
Fixed Maturities
Estimated fair value	$ 1,081,949	$ 1,031,326
Percentage of total	19.50%	18.70%
Managed investments | Investment Grade | BBB [Member]
Fixed Maturities
Estimated fair value	$ 740,861	$ 691,538
Percentage of total	13.40%	12.60%
Managed investments | Non-Investment Grade
Fixed Maturities
Estimated fair value	$ 618,003	$ 664,060
Percentage of total	11.10%	12.00%
Managed investments | Non-Investment Grade | BB [Member]
Fixed Maturities
Estimated fair value	$ 213,568	$ 235,724
Percentage of total	3.90%	4.30%
Managed investments | Non-Investment Grade | B [Member]
Fixed Maturities
Estimated fair value	$ 177,737	$ 179,069
Percentage of total	3.20%	3.20%
Managed investments | Non-Investment Grade | CCC [Member]
Fixed Maturities
Estimated fair value	$ 13,371	$ 5,706
Percentage of total	0.20%	0.10%
Managed investments | Non-Investment Grade | CC [Member]
Fixed Maturities
Estimated fair value	$ 0	$ 1,015
Percentage of total	0.00%	0.00%
Managed investments | Non-Investment Grade | NR [Member]
Fixed Maturities
Estimated fair value	$ 213,327	$ 242,546
Percentage of total	3.80%	4.40%
Non-managed investments
Fixed Maturities
Estimated fair value	$ 158,331	$ 186,379
Percentage of total	2.90%	3.40%
Non-managed investments | Investment Grade
Fixed Maturities
Estimated fair value	$ 0	$ 1,911
Percentage of total	0.00%	0.00%
Non-managed investments | Investment Grade | BBB [Member]
Fixed Maturities
Estimated fair value	$ 0	$ 1,911
Percentage of total	0.00%	0.00%
Non-managed investments | Non-Investment Grade
Fixed Maturities
Estimated fair value	$ 158,331	$ 184,468
Percentage of total	2.90%	3.40%
Non-managed investments | Non-Investment Grade | BB [Member]
Fixed Maturities
Estimated fair value	$ 29,731	$ 70,962
Percentage of total	0.60%	1.30%
Non-managed investments | Non-Investment Grade | B [Member]
Fixed Maturities
Estimated fair value	$ 4,524	$ 30,698
Percentage of total	0.10%	0.60%
Non-managed investments | Non-Investment Grade | NR [Member]
Fixed Maturities
Estimated fair value	$ 124,076	$ 82,808
Percentage of total	2.20%	1.50%

Investments (Maturity profile o

Investments (Maturity profile of fixed maturity investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Maturity profile
Amortized cost	$ 5,584,599	$ 5,556,900
Estimated fair value	5,543,030	5,510,331
Managed investments
Maturity profile
Amortized cost	5,427,113	5,369,053
Estimated fair value	5,384,699	5,323,952
Managed investments | Due in one year or less [Member]
Maturity profile
Amortized cost	350,733	367,132
Estimated fair value	346,161	366,019
Managed investments | Due after one year through five years [Member]
Maturity profile
Amortized cost	2,954,856	2,965,920
Estimated fair value	2,933,146	2,936,053
Managed investments | Due after five years through ten years [Member]
Maturity profile
Amortized cost	430,365	548,183
Estimated fair value	426,647	539,083
Managed investments | Due after ten years [Member]
Maturity profile
Amortized cost	128,508	150,444
Estimated fair value	125,927	148,036
Managed investments | Fixed Maturities Trading Securities Allocated To Contractual Maturity [Member]
Maturity profile
Amortized cost	3,864,462	4,031,679
Estimated fair value	3,831,881	3,989,191
Managed investments | Asset backed and mortgaged backed securities [Member]
Maturity profile
Amortized cost	1,562,651	1,337,374
Estimated fair value	1,552,818	1,334,761
Non-managed investments
Maturity profile
Amortized cost	157,486	187,847
Estimated fair value	158,331	186,379
Non-managed investments | Due in one year or less [Member]
Maturity profile
Amortized cost	43,664	7,504
Estimated fair value	45,418	7,544
Non-managed investments | Due after one year through five years [Member]
Maturity profile
Amortized cost	112,572	165,093
Estimated fair value	111,656	163,575
Non-managed investments | Due after five years through ten years [Member]
Maturity profile
Amortized cost	1,250	15,250
Estimated fair value	1,257	15,260
Non-managed investments | Due after ten years [Member]
Maturity profile
Amortized cost	0	0
Estimated fair value	$ 0	$ 0

Investments (Other investments)

Investments (Other investments) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		$ 405,712	$ 336,856
Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		405,712	336,856
Managed investments | Fund of hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		955	1,417
Managed investments | Hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		17,381	20,980
Managed investments | Private equity investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		89,809	63,771
Managed investments | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		242,093	188,721
Managed investments | Overseas deposits
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		50,106	54,484
Managed investments | Mutual funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		5,368	7,483
Subject to redemption restriction | Managed investments | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		184,749
Recurring | Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		405,712	336,856
Recurring | Managed investments | Fund of hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		955	1,417
Recurring | Managed investments | Hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		17,381	20,980
Recurring | Managed investments | Private equity investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		89,809	63,771
Recurring | Managed investments | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		242,093	188,721
Recurring | Managed investments | Overseas deposits
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		50,106	54,484
Recurring | Managed investments | Mutual funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		5,368	7,483
Recurring | Subject to redemption restriction | Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		369,402	308,562
Recurring | Subject to redemption restriction | Managed investments | Fund of hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		955	1,417
Recurring | Subject to redemption restriction | Managed investments | Hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		17,381	20,980
Recurring | Subject to redemption restriction | Managed investments | Private equity investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		89,809	63,771
Recurring | Subject to redemption restriction | Managed investments | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		211,151	167,910
Recurring | Subject to redemption restriction | Managed investments | Overseas deposits
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		50,106	54,484
Recurring | Subject to redemption restriction | Managed investments | Mutual funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		0	0
Recurring | Not subject to redemption restriction | Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		36,310	28,294
Recurring | Not subject to redemption restriction | Managed investments | Fund of hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		0	0
Recurring | Not subject to redemption restriction | Managed investments | Hedge funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		0	0
Recurring | Not subject to redemption restriction | Managed investments | Private equity investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		0	0
Recurring | Not subject to redemption restriction | Managed investments | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		$ 30,942	$ 20,811
Redemption frequency	[1]	Daily	Daily
Redemption notice period	[1]	2 days	2 days
Recurring | Not subject to redemption restriction | Managed investments | Overseas deposits
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		$ 0	$ 0
Recurring | Not subject to redemption restriction | Managed investments | Mutual funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		$ 5,368	$ 7,483
Redemption frequency	[1]	Daily	Daily
Minimum | Recurring | Subject to redemption restriction | Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Redemption restriction period		5 years
Maximum | Recurring | Subject to redemption restriction | Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Redemption restriction period		10 years
[1]	The redemption frequency and notice periods only apply to investments without redemption restrictions.

Investments (Investments in aff

Investments (Investments in affiliates) (Details) - USD ($) $ in Thousands	Nov. 07, 2014	Oct. 02, 2014	Dec. 20, 2011	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Investment affiliate, beginning of year							$ 87,673					$ 87,673
(Loss) income from investment affiliates				$ 2,166	$ 453	$ (589)	(4,113)	$ (1,261)	$ 2,482	$ 284	$ 2,776	(2,083)	$ 4,281	$ 8,411
Investment affiliate, end of year				100,431				87,673				100,431	87,673
Investments in investment affiliates, at cost				84,840				69,794				$ 84,840	69,794
Aquiline Financial Services Fund II LP
Schedule of Equity Method Investments [Line Items]
Investment time lag reporting												3 months
Related Party Transaction Assumption Of Interest Percentage												100.00%
Capital commitment		$ 10,000	$ 50,000
Aquiline Financial Services Fund III LP
Schedule of Equity Method Investments [Line Items]
Capital commitment	$ 100,000
Investment Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Investment affiliate, beginning of year							87,673				$ 63,506	$ 87,673	63,506
Net capital contributions												14,841	19,886
(Loss) income from investment affiliates												(2,083)	4,281
Investment affiliate, end of year				100,431				87,673				100,431	87,673	$ 63,506
Investments in investment affiliates, at cost				84,840				69,794				84,840	69,794
Investment Affiliates [Member] | Aquiline Financial Services Fund II LP
Schedule of Equity Method Investments [Line Items]
Investment affiliate, beginning of year							73,880					73,880
Investment affiliate, end of year				$ 61,999				$ 73,880				$ 61,999	$ 73,880
Voting ownership %				0.00%				0.00%				0.00%	0.00%
Equity ownership %				8.10%				8.10%				8.10%	8.10%
Investments in investment affiliates, at cost				$ 46,871				$ 55,904				$ 46,871	$ 55,904
Investment Affiliates [Member] | Aquiline Financial Services Fund III LP
Schedule of Equity Method Investments [Line Items]
Investment affiliate, beginning of year							$ 13,793					13,793
Investment affiliate, end of year				$ 38,432				$ 13,793				$ 38,432	$ 13,793
Voting ownership %				0.00%				0.00%				0.00%	0.00%
Equity ownership %				9.00%				13.70%				9.00%	13.70%
Investments in investment affiliates, at cost				$ 37,969				$ 13,890				$ 37,969	$ 13,890

Investments (Components of net

Investments (Components of net investment income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net investment income
Net investment income	$ 38,153	$ 43,514	$ 39,257	$ 29,461	$ 31,612	$ 31,572	$ 33,611	$ 31,029	$ 150,385	$ 127,824	$ 100,086
Managed investments
Net investment income
Total gross investment income									149,939	128,861	103,272
Investment expenses									(8,221)	(7,695)	(7,472)
Net investment income									141,718	121,166	95,800
Managed investments | Fixed maturities and short-term investments
Net investment income
Total gross investment income									119,085	113,627	93,044
Managed investments | Other investments
Net investment income
Total gross investment income									27,860	13,307	5,111
Managed investments | Cash and cash equivalents and restricted cash
Net investment income
Total gross investment income									2,939	1,911	5,106
Managed investments | Securities lending income
Net investment income
Total gross investment income									55	16	11
Non-managed investments
Net investment income
Net investment income									8,667	6,658	4,286
Non-managed investments | Fixed maturities and short-term investments
Net investment income
Total gross investment income									6,931	6,528	4,204
Non-managed investments | Cash and cash equivalents and restricted cash
Net investment income
Total gross investment income									$ 1,736	$ 130	$ 82

Investments (Realized and unrea

Investments (Realized and unrealized gains (losses)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fixed maturities, short-term and other investments
Net realized gains on investments	$ 9,220	$ 4,397	$ 2,724	$ (584)	$ (2,928)	$ (1,187)	$ 2,244	$ 4,169	$ 15,757	$ 2,298	$ 14,917
Change in net unrealized gains (losses) on managed investments (a)	$ (67,460)	$ 5,459	$ 31,428	$ 47,444	$ (34,862)	$ 3,916	$ (34,676)	$ 33,227	16,871	(32,395)	(2,842)
Total net realized gains and change in net unrealized gains (losses) gains on investments									32,628	(30,097)	12,075
Managed investments
Fixed maturities, short-term and other investments
Gross realized gains									22,491	15,678	20,201
Gross realized (losses)									(7,811)	(13,980)	(8,041)
Net realized gains on investments									14,680	1,698	12,160
Change in net unrealized gains (losses) on managed investments (a)									14,106	(32,007)	(1,030)
Total net realized gains and change in net unrealized gains (losses) gains on investments									28,786	(30,309)	11,130
Non-managed investments
Fixed maturities, short-term and other investments
Gross realized gains									1,086	611	2,757
Gross realized (losses)									(9)	(11)	0
Net realized gains on investments									1,077	600	2,757
Change in net unrealized gains (losses) on managed investments (a)									2,765	(388)	(1,812)
Total net realized gains and change in net unrealized gains (losses) gains on investments									$ 3,842	$ 212	$ 945

Investments (Narrative) (Detail

Investments (Narrative) (Details) $ in Thousands	Nov. 07, 2014USD ($)	Dec. 31, 2016USD ($)funds	Dec. 31, 2015USD ($)
Schedule of Trading Securities and Other Trading Assets [Line Items]
Investments pledged as collateral		$ 442,184	$ 826,535
Other investments		$ 405,712	336,856
Securities lending - Percent of market value required in collateral		102.00%
Cash, cash equivalents and investments pledged as collateral		$ 5,173,966	4,056,788
Investments held in trust		5,068,092	4,007,215
Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		405,712	336,856
Managed investments | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		$ 242,093	188,721
Managed investments | Subject to redemption restriction | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Lock Up Period		3 years
Other investments		$ 184,749
Recurring | Managed investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		405,712	336,856
Recurring | Managed investments | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		242,093	188,721
Recurring | Managed investments | Subject to redemption restriction
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		$ 369,402	308,562
Recurring | Managed investments | Subject to redemption restriction | Investment fund A [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other Investments Number Of Funds | funds		1
Recurring | Managed investments | Subject to redemption restriction | Fixed income investment funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Other investments		$ 211,151	$ 167,910
Aquiline Financial Services Fund III LP
Schedule of Trading Securities and Other Trading Assets [Line Items]
Capital commitment	$ 100,000

Fair value measurements (Fair v

Fair value measurements (Fair value hierarchy) (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		$ 5,543,030	$ 5,510,331
Short-term investments		2,796,170	1,941,635
Other investments		405,712	336,856
Investments in investment affiliates		100,431	87,673
Total investments, at fair value		8,845,343	7,876,495
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, at fair value		8,845,343	7,876,495
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, at fair value		2,777,435	1,926,944
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, at fair value		5,279,272	5,307,479
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, at fair value		330,970	245,837
Fair value based on NAV practical expedient | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, at fair value		357,235	308,562
Managed investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		5,384,699	5,323,952
Short-term investments		228,386	237,369
Other investments		405,712	336,856
Investments in investment affiliates	[1]	100,431	87,673
Total investments, at fair value		6,119,228	5,985,850
Managed investments | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		804,126	937,202
Managed investments | Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		240,791	237,968
Managed investments | U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		271,830	301,289
Managed investments | Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		679,595	610,582
Managed investments | Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		15,477	26,920
Managed investments | U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		1,534,508	1,489,951
Managed investments | Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		410,227	446,570
Managed investments | Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		570,399	576,211
Managed investments | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		526,814	437,124
Managed investments | Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		330,932	260,135
Managed investments | Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		955	1,417
Managed investments | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		17,381	20,980
Managed investments | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		89,809	63,771
Managed investments | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		242,093	188,721
Managed investments | Overseas deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		50,106	54,484
Managed investments | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		5,368	7,483
Managed investments | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		5,384,699	5,323,952
Short-term investments		228,386	237,369
Other investments		405,712	336,856
Investments in investment affiliates	[2]	100,431	87,673
Total investments, at fair value		6,119,228	5,985,850
Managed investments | Recurring | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		804,126	937,202
Managed investments | Recurring | Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		240,791	237,968
Managed investments | Recurring | U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		271,830	301,289
Managed investments | Recurring | Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		679,595	610,582
Managed investments | Recurring | Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		15,477	26,920
Managed investments | Recurring | U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		1,534,508	1,489,951
Managed investments | Recurring | Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		410,227	446,570
Managed investments | Recurring | Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		570,399	576,211
Managed investments | Recurring | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		526,814	437,124
Managed investments | Recurring | Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		330,932	260,135
Managed investments | Recurring | Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		955	1,417
Managed investments | Recurring | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		17,381	20,980
Managed investments | Recurring | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		89,809	63,771
Managed investments | Recurring | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		242,093	188,721
Managed investments | Recurring | Overseas deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		50,106	54,484
Managed investments | Recurring | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		5,368	7,483
Managed investments | Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Short-term investments		209,651	222,678
Other investments		0	0
Total investments, at fair value		209,651	222,678
Managed investments | Recurring | Level 1 | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 1 | Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 1 | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 1 | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 1 | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 1 | Overseas deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 1 | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		5,114,272	5,091,615
Short-term investments		18,735	14,691
Other investments		36,309	28,294
Total investments, at fair value		5,169,316	5,134,600
Managed investments | Recurring | Level 2 | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		804,126	937,202
Managed investments | Recurring | Level 2 | Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		240,791	237,968
Managed investments | Recurring | Level 2 | U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		271,830	301,289
Managed investments | Recurring | Level 2 | Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		679,595	610,582
Managed investments | Recurring | Level 2 | Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		15,477	26,920
Managed investments | Recurring | Level 2 | U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		1,534,508	1,489,951
Managed investments | Recurring | Level 2 | Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		410,227	446,570
Managed investments | Recurring | Level 2 | Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		323,903	343,874
Managed investments | Recurring | Level 2 | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		502,883	437,124
Managed investments | Recurring | Level 2 | Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		330,932	260,135
Managed investments | Recurring | Level 2 | Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 2 | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 2 | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 2 | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		30,941	20,811
Managed investments | Recurring | Level 2 | Overseas deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 2 | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		5,368	7,483
Managed investments | Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		270,427	232,337
Short-term investments		0	0
Other investments		12,168	0
Total investments, at fair value		282,595	232,337
Managed investments | Recurring | Level 3 | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		246,496	232,337
Managed investments | Recurring | Level 3 | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		23,931	0
Managed investments | Recurring | Level 3 | Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Recurring | Level 3 | Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 3 | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 3 | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 3 | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		12,168	0
Managed investments | Recurring | Level 3 | Overseas deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Recurring | Level 3 | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Short-term investments		0	0
Other investments		357,235	308,562
Total investments, at fair value		357,235	308,562
Managed investments | Fair value based on NAV practical expedient | Recurring | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Managed investments | Fair value based on NAV practical expedient | Recurring | Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		955	1,417
Managed investments | Fair value based on NAV practical expedient | Recurring | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		17,381	20,980
Managed investments | Fair value based on NAV practical expedient | Recurring | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		89,809	63,771
Managed investments | Fair value based on NAV practical expedient | Recurring | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		198,984	167,910
Managed investments | Fair value based on NAV practical expedient | Recurring | Overseas deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		50,106	54,484
Managed investments | Fair value based on NAV practical expedient | Recurring | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments		0	0
Non-managed investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		158,331	186,379
Short-term investments		2,567,784	1,704,266
Total investments, at fair value		2,726,115	1,890,645
Non-managed investments | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		158,331	186,379
Non-managed investments | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		2,567,784	1,704,266
Total investments, at fair value		2,726,115	1,890,645
Non-managed investments | Recurring | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		158,331	186,379
Non-managed investments | Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		2,567,784	1,704,266
Total investments, at fair value		2,567,784	1,704,266
Non-managed investments | Recurring | Level 1 | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		0	0
Non-managed investments | Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		0	0
Total investments, at fair value		109,956	172,879
Non-managed investments | Recurring | Level 2 | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		109,956	172,879
Non-managed investments | Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		0	0
Total investments, at fair value		48,375	13,500
Non-managed investments | Recurring | Level 3 | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		48,375	13,500
Non-managed investments | Fair value based on NAV practical expedient | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		0	0
Total investments, at fair value		0	0
Non-managed investments | Fair value based on NAV practical expedient | Recurring | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities, at fair value		$ 0	$ 0
[1]	The Company’s investments in investment affiliates have been treated as equity method investments with the corresponding gains and losses recorded inincome as “Income (loss) from investment affiliates.”
[2]	In accordance with ASC Topic 825 “Financial Instruments,” the Company’s investments in investment affiliates have not been classified in the fair value hierarchy.

Fair value measurements (Level

Fair value measurements (Level 3 rollforward) (Details) - Recurring - Level 3 - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of year	$ 245,837	$ 50,248
Purchases	156,681	230,070
Sales	(2,389)	(5,025)
Settlements	(69,621)	(27,429)
Net realized losses		(11)
Change in net unrealized (losses) gains	462	(2,016)
Level 3, end of year	330,970	245,837
Bank Loan Portfolio
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of year	232,337	32,748
Purchases	87,345	230,070
Sales	(2,389)	(1,036)
Settlements	(69,496)	(27,429)
Net realized losses		0
Change in net unrealized (losses) gains	(1,301)	(2,016)
Level 3, end of year	246,496	232,337
Catastrophe bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of year	13,500	17,500
Purchases	33,272	0
Sales	0	(3,989)
Settlements	(125)	0
Net realized losses		(11)
Change in net unrealized (losses) gains	1,728	0
Level 3, end of year	48,375	13,500
Fixed income investment funds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of year	0
Purchases	12,168
Sales	0
Settlements	0
Change in net unrealized (losses) gains	0
Level 3, end of year	12,168	0
Asset-backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of year	0
Purchases	23,896
Sales	0
Settlements	0
Change in net unrealized (losses) gains	35
Level 3, end of year	$ 23,931	$ 0

Fair value measurements (Narrat

Fair value measurements (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	$ 8,845,343	$ 7,876,495
Managed investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	6,119,228	5,985,850
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	$ 8,845,343	7,876,495
Recurring | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	3 months
Recurring | Hedge fund side pocket
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	3 months
Recurring | Minimum | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	1 month
Recurring | Minimum | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	3 months
Recurring | Maximum | Fixed income investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	3 months
Recurring | Maximum | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	6 months
Recurring | Managed investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	$ 6,119,228	5,985,850
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers into Level 3 during the year	0	0
Total investments	330,970	245,837
Recurring | Level 3 | Managed investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	$ 282,595	$ 232,337
Ratio of Level 3 investments to total investments (percent)	4.60%	3.90%

Variable interest entities (Not

Variable interest entities (Notes Payable to AlphaCat Investors) (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016USD ($)funds	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)funds	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Variable Interest Entity [Line Items]
Income attributable to AlphaCat investors	$ 7,080	$ 5,564	$ 6,114	$ 4,600	$ 974	$ 1,438	$ 0	$ 0	$ 23,358	$ 2,412	$ 0
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Notes payable to AlphaCat investors, beginning of year				75,493				0	75,493	0
Issuance of notes payable to AlphaCat investors									406,037	75,770
Variable Interest Entity Redemption Of Notes Payable To AlphaCat Investors									204,038
Foreign exchange losses									710	(277)
Notes payable to AlphaCat investors, end of year	$ 278,202				75,493				$ 278,202	75,493	0
Variable Funding Notes, Typical Minimum Duration									12 months
AlphaCat ILS Funds
Variable Interest Entity [Line Items]
Number Of Funds | funds	1								1
AlphaCat ILS Funds | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Risk Profile Percentage									7.00%
Variable Funding Note [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Notes payable to AlphaCat investors, beginning of year				75,493				0	$ 75,493	0
Issuance of notes payable to AlphaCat investors									311,711	75,770
Variable Interest Entity Redemption Of Notes Payable To AlphaCat Investors									109,712
Foreign exchange losses									710	(277)
Notes payable to AlphaCat investors, end of year	$ 278,202				75,493				$ 278,202	75,493	0
Structured Note [Member]
Variable Interest Entity [Line Items]
Structured Notes Interest Rate Percentage									8.00%
Structured Note [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Notes payable to AlphaCat investors, beginning of year				$ 0				$ 0	$ 0	0
Issuance of notes payable to AlphaCat investors									94,326	0
Variable Interest Entity Redemption Of Notes Payable To AlphaCat Investors									94,326
Foreign exchange losses									0	0
Notes payable to AlphaCat investors, end of year	$ 0				$ 0				0	0	$ 0
Accounts payable and accrued expenses
Variable Interest Entity [Line Items]
Variable Interest Entity Redemption Of Notes Payable To AlphaCat Investors									1,000
Income attributable to AlphaCat investors									$ 17,068	$ 2,412

Variable interest entities (Ass

Variable interest entities (Assets and Liabilities of Consolidated VIEs) (Details) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2016USD ($)subsidiaries	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)subsidiaries	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Variable Interest Entity [Line Items]
(Income) attributable to AlphaCat investors		$ (7,080)	$ (5,564)	$ (6,114)	$ (4,600)	$ (974)	$ (1,438)	$ 0	$ 0	$ (23,358)	$ (2,412)	$ 0
Accounts payable and accrued expenses
Variable Interest Entity [Line Items]
(Income) attributable to AlphaCat investors										$ (17,068)	(2,412)
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Variable Funding Notes, Typical Minimum Duration										12 months
AlphaCat Sidecars | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Total assets		40,041				206,581				$ 40,041	206,581
Total liabilities		3,206				14,804				3,206	14,804
AlphaCat ILS Funds - Lower Risk (a) | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Total assets	[1]	1,498,276				1,268,070				1,498,276	1,268,070
Total liabilities	[1]	42,457				143,371				42,457	143,371
AlphaCat ILS Funds - Higher Risk (a) | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Total assets	[1]	972,633				522,867				972,633	522,867
Total liabilities	[1]	381,332				300,122				381,332	300,122
AlphaCat Re & Master Fund | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Total assets		2,510,415				1,615,779				2,510,415	1,615,779
Total liabilities		$ 2,510,245				1,615,609				$ 2,510,245	1,615,609
BetaCat ILS Funds | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Number of Consolidated Funds | subsidiaries		1								1
Total assets		$ 82,471				64,221				$ 82,471	64,221
Total liabilities		$ 30,663				$ 2,472				$ 30,663	$ 2,472
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Noncontrolling interests (Detai

Noncontrolling interests (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Noncontrolling Interest [Line Items]
Total, beginning of period				$ 1,266,376				$ 910,065	$ 1,266,376	$ 910,065
Issuance of shares									565,124	508,800
Income attributable to noncontrolling interest	$ 27,200	$ 37,439	$ 21,193	37,531	$ 25,996	$ 26,229	$ 22,561	18,178	123,363	92,964	$ 74,880
Redemption of shares / Distributions									(260,885)	(245,453)
Total, end of period	1,693,978				1,266,376				1,693,978	1,266,376	910,065
Redeemable Noncontrolling Interest
Noncontrolling Interest [Line Items]
Total, beginning of period				1,111,714				617,791	1,111,714	617,791
Issuance of shares									393,450	499,200
Income attributable to noncontrolling interest									100,852	71,418
Redemption of shares / Distributions									(78,015)	(76,695)
Total, end of period	1,528,001				1,111,714				1,528,001	1,111,714	617,791
Amounts payable to concontrolling interest	71,530				10,800				71,530	10,800
Noncontrolling Interest
Noncontrolling Interest [Line Items]
Total, beginning of period				$ 154,662				$ 292,274	154,662	292,274
Issuance of shares									171,674	9,600
Income attributable to noncontrolling interest									22,511	21,546
Redemption of shares / Distributions									(182,870)	(168,758)
Total, end of period	165,977				154,662				165,977	154,662	$ 292,274
Amounts payable to concontrolling interest	$ 16,144				$ 0				$ 16,144	$ 0

Investment in operating affil88

Investment in operating affiliate (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				$ 392					$ 392
Loss from operating affiliate	$ 0	$ 0	$ 0	(23)	$ (1,708)	$ (7,963)	$ 1,738	$ 3,984	(23)	$ (3,949)	$ (4,340)
Balance, end of period	0				392				0	392
Operating Affiliates | PacRe
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				$ 392				$ 50,944	392	50,944
Return of investment									(369)	(46,603)
Loss from operating affiliate									(23)	(3,949)
Balance, end of period	$ 0				392				$ 0	392	$ 50,944
Investment at cost					$ 392					$ 392
Voting ownership %					100.00%					100.00%
Equity ownership %					10.00%					10.00%

Derivative instruments (Amount

Derivative instruments (Amount and balance sheet location) (Details) $ in Thousands	Dec. 31, 2016USD ($)derivatives	Dec. 31, 2015USD ($)
Interest rate swap contracts
Summary of amount of derivatives designated as hedging instruments
Derivative, Number of Instruments Held | derivatives	2
Not designated as hedging instruments | Foreign currency forward contracts
Summary of amount of derivatives designated as hedging instruments
Notional amount	$ 181,375	$ 255,840
Not designated as hedging instruments | Foreign currency forward contracts | Other assets
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative assets	2,351	2,601
Not designated as hedging instruments | Foreign currency forward contracts | Accounts payable and accrued expenses
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative liabilities	3,421	3,211
Designated as hedging instruments | Interest rate swap contracts
Summary of amount of derivatives designated as hedging instruments
Notional amount	552,263	552,263
Designated as hedging instruments | Interest rate swap contracts | Other assets
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative assets	20	21
Designated as hedging instruments | Interest rate swap contracts | Accounts payable and accrued expenses
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative liabilities	$ 1,479	$ 1,942

Derivative instruments (Amoun90

Derivative instruments (Amount included in statement of operations) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Not designated as hedging instruments | Foreign exchange gain (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ (1,667)	$ (610)	$ 0
Not designated as hedging instruments | Other Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	142	139	(133)
Not designated as hedging instruments | Gain (Loss) on Investments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	8,518	0	0
Designated as hedging instruments | Fair value hedge | Foreign currency forward contracts | Foreign exchange gain (loss)
Derivatives designated as fair value hedges and related hedged item
Amount of gain (loss) recognized in income on derivative	0	(12,279)	(9,651)
Amount of gain (loss) on hedged item recognized in income attributable to risk being hedged	0	12,279	9,651
Amount of gain (loss) recognized in income on derivative (ineffective portion)	0		0
Designated as hedging instruments | Cash flow hedge | Interest rate swap contracts
Derivative Instruments designated as a cash flow hedge
Amount of ineffective portion excluded from effectiveness testing	277	(841)	(228)
Designated as hedging instruments | Cash flow hedge | Interest rate swap contracts | Other comprehensive income
Derivative Instruments designated as a cash flow hedge
Amount of effective portion recognized in other comprehensive income	10,584	13,740	13,302
Designated as hedging instruments | Cash flow hedge | Interest rate swap contracts | Finance expenses
Derivative Instruments designated as a cash flow hedge
Amount of effective portion subsequently reclassified to earnings	$ (10,861)	$ (12,899)	$ (13,074)

Premiums receivable (Details)

Premiums receivable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Premiums Receivable Reconciliation [Line Items]
Balance at beginning of period	$ 658,682	$ 706,467
Change in premiums receivable during period	66,708	(47,785)
Balance at end of period	725,390	658,682
Premiums in course of collection
Premiums Receivable Reconciliation [Line Items]
Balance at beginning of period	95,152	84,901
Change in premiums receivable during period	6,250	10,251
Balance at end of period	101,402	95,152
Premiums accrued but unbilled
Premiums Receivable Reconciliation [Line Items]
Balance at beginning of period	563,530	621,566
Change in premiums receivable during period	60,458	(58,036)
Balance at end of period	$ 623,988	$ 563,530

Reserve for losses and loss e92

Reserve for losses and loss expenses (Analysis of paid and unpaid losses and reconciliation of beginning and ending unpaid losses and loss expenses) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Reserve for losses and loss expenses, beginning of year				$ 2,996,567				$ 3,243,147	$ 2,996,567	$ 3,243,147	$ 3,047,933
Loss reserves recoverable, beginning of year				(350,586)				(377,466)	(350,586)	(377,466)	(370,154)
Net reserve for losses and loss expenses, beginning of year				2,645,981				2,865,681	2,645,981	2,865,681	2,677,779
Net reserves acquired									0	0	525,091
Increase (decrease) in net losses and loss expenses incurred in respect of losses occurring in:
Current year									1,281,289	1,283,970	1,024,256
Prior years									(216,192)	(306,137)	(259,241)
Total incurred losses and loss expenses									1,065,097	977,833	765,015
Less net losses and loss expenses paid in respect of losses occurring in:
Current year									(389,234)	(326,167)	(245,084)
Prior years									(725,168)	(841,672)	(818,569)
Total net paid losses									(1,114,402)	(1,167,839)	(1,063,653)
Foreign exchange gain									(31,902)	(29,694)	(38,551)
Net reserve for losses and loss expenses, end of year	$ 2,564,774				$ 2,645,981				2,564,774	2,645,981	2,865,681
Loss reserves recoverable, end of year	(430,421)				(350,586)				(430,421)	(350,586)	(377,466)
Reserve for losses and loss expenses, end of year	2,995,195				2,996,567				2,995,195	2,996,567	3,243,147
Incurred losses and loss adjustment expenses comprise:
Gross losses and loss adjustment expenses									1,257,054	1,083,695	826,826
Reinsurance recoverable									(191,957)	(105,862)	(61,811)
Net incurred losses and loss expenses	275,126	$ 258,394	$ 307,130	$ 224,447	214,748	$ 256,010	$ 266,146	$ 240,929	1,065,097	977,833	$ 765,015
Liability for unpaid losses and loss expenses by type
Reserves, reported claims	1,237,772				1,278,697				1,237,772	1,278,697
Reserves, incurred but not reported claims	$ 1,757,423				$ 1,717,870				$ 1,757,423	$ 1,717,870

Reserve for losses and loss e93

Reserve for losses and loss expenses (Prior year development) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	$ (216,192)	$ (306,137)	$ (259,241)
Property
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(100,815)	(136,978)	(148,055)
Marine
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(36,173)	(103,380)	(38,227)
Specialty
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(72,793)	(48,857)	(60,696)
Liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(6,411)	(16,922)	(12,263)
Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(118,533)	(128,616)	(87,600)
Validus Re | Property
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(57,888)	(70,343)	(76,064)
Validus Re | Marine
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(24,435)	(39,460)	(6,830)
Validus Re | Specialty
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(36,210)	(18,813)	(4,706)
Validus Re | Liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	0	0	0
Talbot
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(85,810)	(146,357)	(141,166)
Talbot | Property
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(38,368)	(52,393)	(53,779)
Talbot | Marine
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(11,738)	(63,920)	(31,397)
Talbot | Specialty
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(35,704)	(30,044)	(55,990)
Talbot | Liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	0	0	0
Western World Insurance Group, Inc
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(9,112)	(22,967)	(11,240)
Western World Insurance Group, Inc | Property
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(2,701)	(6,045)	1,023
Western World Insurance Group, Inc | Marine
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	0	0	0
Western World Insurance Group, Inc | Specialty
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	0	0	0
Western World Insurance Group, Inc | Liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(6,411)	(16,922)	(12,263)
AlphaCat
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(2,737)	(8,197)	(19,235)
AlphaCat | Property
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(1,858)	(8,197)	(19,235)
AlphaCat | Marine
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	0	0	0
AlphaCat | Specialty
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	(879)	0	0
AlphaCat | Liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Net favorable development on prior years	$ 0	$ 0	$ 0

Reserve for losses and loss e94

Reserve for losses and loss expenses (Claims development triangles) (Details) $ in Thousands	Dec. 31, 2016USD ($)Claims	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Dec. 31, 2012USD ($)	Dec. 31, 2011USD ($)	Dec. 31, 2010USD ($)	Dec. 31, 2009USD ($)	Dec. 31, 2008USD ($)	Dec. 31, 2007USD ($)
Claims Development [Line Items]
Reserves for losses and loss expenses, net of reinsurance	$ 2,459,039
Validus Re | Property
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	776,380
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	511,432
Liabilities for losses and loss expenses, before 2012, net of reinsurance	154,539
Reserves for losses and loss expenses, net of reinsurance	419,487
Validus Re | Property | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	149,263
Total of IBNR Reserves Plus Expected Development on Reported Losses	86,564
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	26,522
Validus Re | Property | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	118,484	$ 154,923
Total of IBNR Reserves Plus Expected Development on Reported Losses	41,177
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	57,882	16,029
Validus Re | Property | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	95,392	102,273	$ 108,206
Total of IBNR Reserves Plus Expected Development on Reported Losses	6,757
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	78,509	63,415	25,346
Validus Re | Property | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	132,830	141,203	156,233	$ 174,722
Total of IBNR Reserves Plus Expected Development on Reported Losses	7,233
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	114,263	101,158	63,974	17,325
Validus Re | Property | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	280,411	282,517	309,344	321,956	$ 397,635
Total of IBNR Reserves Plus Expected Development on Reported Losses	19,108
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	234,256	225,518	202,141	149,433	67,004
Validus Re | Marine
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	501,814
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	265,048
Liabilities for losses and loss expenses, before 2012, net of reinsurance	64,750
Reserves for losses and loss expenses, net of reinsurance	301,516
Validus Re | Marine | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	68,531
Total of IBNR Reserves Plus Expected Development on Reported Losses	49,619
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	8,801
Validus Re | Marine | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	119,490	129,864
Total of IBNR Reserves Plus Expected Development on Reported Losses	55,557
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	16,180	3,723
Validus Re | Marine | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	35,910	42,991	63,732
Total of IBNR Reserves Plus Expected Development on Reported Losses	7,418
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	17,383	11,749	7,013
Validus Re | Marine | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	61,210	63,630	74,022	76,776
Total of IBNR Reserves Plus Expected Development on Reported Losses	7,347
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	44,512	39,493	28,996	11,784
Validus Re | Marine | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	216,673	218,734	225,131	226,817	195,163
Total of IBNR Reserves Plus Expected Development on Reported Losses	19,725
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	178,172	169,420	148,628	94,052	11,356
Validus Re | Specialty
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	997,132
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	773,669
Liabilities for losses and loss expenses, before 2012, net of reinsurance	67,909
Reserves for losses and loss expenses, net of reinsurance	291,372
Validus Re | Specialty | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	295,872
Total of IBNR Reserves Plus Expected Development on Reported Losses	128,761
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	149,502
Validus Re | Specialty | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	279,766	296,554
Total of IBNR Reserves Plus Expected Development on Reported Losses	32,236
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	235,819	177,776
Validus Re | Specialty | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	200,649	208,508	213,911
Total of IBNR Reserves Plus Expected Development on Reported Losses	8,372
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	176,202	162,056	95,765
Validus Re | Specialty | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	174,219	178,736	190,470	182,297
Total of IBNR Reserves Plus Expected Development on Reported Losses	1,974
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	166,814	164,366	157,688	99,340
Validus Re | Specialty | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	46,626	47,428	49,263	54,573	53,798
Total of IBNR Reserves Plus Expected Development on Reported Losses	733
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	45,332	44,942	44,037	41,156	17,716
Talbot | Property
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	584,008
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	363,041
Liabilities for losses and loss expenses, before 2012, net of reinsurance	12,180
Reserves for losses and loss expenses, net of reinsurance	233,147
Talbot | Property | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	177,771
Total of IBNR Reserves Plus Expected Development on Reported Losses	76,755
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	37,880
Talbot | Property | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	109,608	138,087
Total of IBNR Reserves Plus Expected Development on Reported Losses	12,696
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	63,437	24,537
Talbot | Property | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	114,852	121,260	147,259
Total of IBNR Reserves Plus Expected Development on Reported Losses	5,528
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	95,945	74,493	21,249
Talbot | Property | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	81,004	83,426	96,814	118,167
Total of IBNR Reserves Plus Expected Development on Reported Losses	605
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	73,267	67,328	48,231	12,813
Talbot | Property | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	100,773	101,387	100,748	112,488	135,923
Total of IBNR Reserves Plus Expected Development on Reported Losses	2,413
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	92,512	88,150	83,824	61,490	13,051
Talbot | Marine
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	846,754
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	494,362
Liabilities for losses and loss expenses, before 2012, net of reinsurance	44,753
Reserves for losses and loss expenses, net of reinsurance	397,145
Talbot | Marine | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	159,153
Total of IBNR Reserves Plus Expected Development on Reported Losses	89,536
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	35,105
Talbot | Marine | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	192,818	187,790
Total of IBNR Reserves Plus Expected Development on Reported Losses	54,285
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	73,957	25,300
Talbot | Marine | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	154,105	155,361	180,401
Total of IBNR Reserves Plus Expected Development on Reported Losses	13,671
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	102,788	74,547	24,433
Talbot | Marine | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	161,839	168,203	188,991	189,091
Total of IBNR Reserves Plus Expected Development on Reported Losses	11,372
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	125,037	112,781	88,494	38,416
Talbot | Marine | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	178,839	182,283	186,278	203,855	208,883
Total of IBNR Reserves Plus Expected Development on Reported Losses	5,154
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	157,475	153,550	136,335	105,600	36,491
Talbot | Specialty
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	757,365
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	460,492
Liabilities for losses and loss expenses, before 2012, net of reinsurance	45,486
Reserves for losses and loss expenses, net of reinsurance	342,359
Talbot | Specialty | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	166,604
Total of IBNR Reserves Plus Expected Development on Reported Losses	105,142
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	33,468
Talbot | Specialty | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	149,031	152,907
Total of IBNR Reserves Plus Expected Development on Reported Losses	39,447
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	85,397	35,724
Talbot | Specialty | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	198,653	214,962	215,960
Total of IBNR Reserves Plus Expected Development on Reported Losses	39,248
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	135,526	107,882	41,183
Talbot | Specialty | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	124,208	132,797	145,905	166,450
Total of IBNR Reserves Plus Expected Development on Reported Losses	8,724
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	100,213	91,940	77,428	42,325
Talbot | Specialty | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	118,869	120,621	122,760	132,735	151,306
Total of IBNR Reserves Plus Expected Development on Reported Losses	5,886
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	105,888	87,753	83,201	57,906	25,591
Western World Insurance Group, Inc | Property
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	193,722
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	174,956
Liabilities for losses and loss expenses, before 2012, net of reinsurance	0
Reserves for losses and loss expenses, net of reinsurance	18,766
Western World Insurance Group, Inc | Property | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	46,636
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 9,324
Cumulative Reported Claims Count | Claims	1,587
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 29,666
Western World Insurance Group, Inc | Property | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	26,002	27,879
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 135
Cumulative Reported Claims Count | Claims	1,788
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 25,302	18,981
Western World Insurance Group, Inc | Property | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	28,619	29,282	35,612
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 103
Cumulative Reported Claims Count | Claims	2,393
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 27,606	27,211	21,913
Western World Insurance Group, Inc | Property | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	23,599	23,659	23,561	21,825
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 0
Cumulative Reported Claims Count | Claims	1,950
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 23,561	23,104	22,647	15,568
Western World Insurance Group, Inc | Property | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	15,522	15,556	15,594	15,491	15,506
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 0
Cumulative Reported Claims Count | Claims	1,680
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 15,522	15,513	15,435	14,838	11,166
Western World Insurance Group, Inc | Property | 2011
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	12,021	12,012	12,134	12,000	12,223	$ 12,588
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 0
Cumulative Reported Claims Count | Claims	1,238
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 12,021	12,009	12,027	11,976	12,000	9,797
Western World Insurance Group, Inc | Property | 2010
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	11,332	11,438	11,448	11,414	11,507	11,573	$ 11,846
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 0
Cumulative Reported Claims Count | Claims	974
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 11,287	10,903	10,882	10,854	10,905	10,521	8,563
Western World Insurance Group, Inc | Property | 2009
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	10,060	10,060	10,060	10,060	10,034	10,039	10,005	$ 10,300
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 0
Cumulative Reported Claims Count | Claims	784
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 10,060	10,060	10,060	10,060	10,003	9,942	9,948	8,096
Western World Insurance Group, Inc | Property | 2008
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	11,724	11,724	11,724	11,721	11,729	11,762	11,805	11,615	$ 12,094
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 0
Cumulative Reported Claims Count | Claims	412
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 11,724	11,724	11,724	11,721	11,714	11,747	11,672	11,288	8,895
Western World Insurance Group, Inc | Property | 2007
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	8,207	8,207	8,207	8,206	8,206	8,209	8,209	8,218	8,161	$ 8,520
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 0
Cumulative Reported Claims Count | Claims	841
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 8,207	8,207	8,207	8,206	8,206	8,206	8,206	8,192	7,968	5,418
Western World Insurance Group, Inc | Liability
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	1,296,661
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	850,358
Liabilities for losses and loss expenses, before 2012, net of reinsurance	8,944
Reserves for losses and loss expenses, net of reinsurance	455,247
Western World Insurance Group, Inc | Liability | 2016
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	133,303
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 104,906
Cumulative Reported Claims Count | Claims	3,156
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 9,873
Western World Insurance Group, Inc | Liability | 2015
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	158,591	154,184
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 76,092
Cumulative Reported Claims Count | Claims	5,152
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 39,598	12,662
Western World Insurance Group, Inc | Liability | 2014
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	203,592	197,388	197,022
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 44,988
Cumulative Reported Claims Count | Claims	7,469
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 98,848	52,543	16,468
Western World Insurance Group, Inc | Liability | 2013
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	158,329	164,428	165,233	132,077
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 17,049
Cumulative Reported Claims Count | Claims	5,990
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 108,613	77,776	41,782	10,159
Western World Insurance Group, Inc | Liability | 2012
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	127,486	132,562	133,990	111,283	108,981
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 9,410
Cumulative Reported Claims Count | Claims	4,649
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 108,409	92,499	65,437	31,291	8,823
Western World Insurance Group, Inc | Liability | 2011
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	108,301	109,183	109,412	107,827	107,741	101,091
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 4,627
Cumulative Reported Claims Count | Claims	4,372
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 96,780	88,415	75,000	50,197	27,438	7,331
Western World Insurance Group, Inc | Liability | 2010
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	103,973	106,066	105,400	112,072	111,675	108,823	101,223
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 3,877
Cumulative Reported Claims Count | Claims	4,205
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 96,309	92,889	84,320	71,430	51,765	28,393	8,215
Western World Insurance Group, Inc | Liability | 2009
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	95,266	96,235	98,261	116,327	116,463	116,990	116,780	116,474
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 2,173
Cumulative Reported Claims Count | Claims	3,955
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 90,415	89,688	85,644	77,895	65,009	48,255	30,131	10,023
Western World Insurance Group, Inc | Liability | 2008
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	101,478	102,070	102,424	129,559	131,006	133,088	135,330	135,280	135,009
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 2,075
Cumulative Reported Claims Count | Claims	4,950
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 97,475	95,773	93,563	89,433	82,661	71,239	51,165	28,467	8,654
Western World Insurance Group, Inc | Liability | 2007
Claims Development [Line Items]
Incurred Losses and Loss Expenses, Net of Reinsurance	106,342	107,350	107,894	149,994	152,163	154,499	158,478	160,117	162,239	164,717
Total of IBNR Reserves Plus Expected Development on Reported Losses	$ 1,981
Cumulative Reported Claims Count | Claims	4,727
Cumulative Paid Losses and Loss Expenses, Net of Reinsurance	$ 104,038	$ 103,961	$ 102,600	$ 99,978	$ 96,658	$ 91,020	$ 80,218	$ 58,358	$ 30,741	$ 10,723

Reserve for losses and loss e95

Reserve for losses and loss expenses (Reconciliation of loss development information to reserves for losses and loss expenses) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	$ 2,459,039
Loss reserves recoverable	430,421	$ 350,586	$ 377,466	$ 370,154
Unallocated loss adjustment expenses	51,990
Allowance for reinsurance recoverable	5,153	4,997
Other	58
Reserve for losses and loss expenses	2,995,195	$ 2,996,567	$ 3,243,147	$ 3,047,933
Validus Re | Property
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	419,487
Loss reserves recoverable	42,873
Validus Re | Marine
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	301,516
Loss reserves recoverable	52,970
Validus Re | Specialty
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	291,372
Loss reserves recoverable	2,162
Talbot | Property
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	233,147
Loss reserves recoverable	93,774
Talbot | Marine
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	397,145
Loss reserves recoverable	125,677
Talbot | Specialty
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	342,359
Loss reserves recoverable	86,587
Western World Insurance Group, Inc | Property
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	18,766
Loss reserves recoverable	187
Western World Insurance Group, Inc | Liability
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserves for losses and loss expenses, net of reinsurance	455,247
Loss reserves recoverable	87,300
AlphaCat
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Reserve for losses and loss expenses	48,534
Corporate & Eliminations
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Loss reserves recoverable	$ (61,109)

Reserve for losses and loss e96

Reserve for losses and loss expenses (Historical loss duration) (Details)	Dec. 31, 2016
Validus Re | Property
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	19.00%
Year 2	34.90%
Year 3	20.90%
Year 4	9.10%
Year 5	3.10%
Validus Re | Marine
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	12.00%
Year 2	22.50%
Year 3	19.30%
Year 4	8.90%
Year 5	4.00%
Validus Re | Specialty
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	51.40%
Year 2	34.40%
Year 3	5.70%
Year 4	1.70%
Year 5	0.80%
Talbot | Property
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	18.20%
Year 2	43.40%
Year 3	21.50%
Year 4	5.80%
Year 5	4.30%
Talbot | Marine
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	19.00%
Year 2	31.80%
Year 3	16.80%
Year 4	8.60%
Year 5	2.20%
Talbot | Specialty
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	24.10%
Year 2	30.60%
Year 3	15.60%
Year 4	5.20%
Year 5	15.30%
Western World Insurance Group, Inc | Property
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	73.10%
Year 2	22.40%
Year 3	2.00%
Year 4	0.50%
Year 5	0.10%
Year 6	0.10%
Year 7	0.90%
Year 8	0.00%
Year 9	0.00%
Year 10	0.00%
Western World Insurance Group, Inc | Liability
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Year 1	8.10%
Year 2	18.90%
Year 3	22.90%
Year 4	20.10%
Year 5	12.00%
Year 6	7.20%
Year 7	3.70%
Year 8	1.80%
Year 9	1.50%
Year 10	0.10%

Reserve for losses and loss e97

Reserve for losses and loss expenses (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2013
Liability for Claims and Claims Adjustment Expense [Line Items]
Reserve for losses and loss expenses	$ 2,996,567	$ 3,243,147	$ 2,995,195	$ 3,047,933
Western World Insurance Group, Inc
Liability for Claims and Claims Adjustment Expense [Line Items]
Fair value adjustment to net reserves	15,586
Amortized to income during the period	$ 10,979	$ 4,607
AlphaCat
Liability for Claims and Claims Adjustment Expense [Line Items]
Percentage of Total Reserves			1.90%
Reserve for losses and loss expenses			$ 48,534
Property | Western World Insurance Group, Inc
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			0
Property | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			154,539
Property | Flagstone [Member] | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			77,790
Property | IPC [Member] | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			10,614
Marine | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			64,750
Marine | Flagstone [Member] | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			15,178
Marine | IPC [Member] | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			1,537
Specialty | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			67,909
Specialty | Flagstone [Member] | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			41,091
Specialty | IPC [Member] | Validus Re
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss expenses, before 2012, net of reinsurance			$ 5,743

Accounts payable and accrued 98

Accounts payable and accrued expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts Payable and Accrued Liabilities [Abstract]
Accrued interest on debt	$ 10,286	$ 10,771
Subscriptions received in advance on AlphaCat ILS funds and sidecars	326,900	412,036
Redemptions made on AlphaCat ILS funds	87,674	10,800
Structured notes payable	1,000	0
Accrued income attributable to AlphaCat investors	17,068	2,412
Income tax payable	1,036	8,856
Accrued pension liability	16,979	15,722
Trade and compensation payables	126,705	166,734
Total	587,648	627,331
Noncash Movements Related to Variable Interest Entities	217,322	(10,239)	$ 7,847
Noncash Movements Related to Redemptions	77,873	(10,239)	7,847
Noncash Movements Related to Subscriptions	$ 139,449	$ 0	$ 0

Reinsurance (Components of rein

Reinsurance (Components of reinsurance recoverable) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reinsurance Disclosures [Abstract]
Case reserves	$ 165,328	$ 135,723
IBNR	265,093	214,863
Loss reserves recoverable	430,421	350,586	$ 377,466	$ 370,154
Paid losses recoverable	35,247	23,071
Total reinsurance recoverable	$ 465,668	$ 373,657

Reinsurance (Effect on premiums

Reinsurance (Effect on premiums written and earned) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Written:
Treaty reinsurance									$ 1,501,079	$ 1,393,440	$ 1,340,939
Facultative reinsurance									293,741	325,311	334,898
Direct									853,885	838,755	683,028
Ceded	$ (40,635)	$ (45,006)	$ (36,229)	$ (167,835)	$ (33,128)	$ (48,810)	$ (55,418)	$ (191,325)	(289,705)	(328,681)	(313,208)
Net premiums written	298,819	327,412	727,813	1,004,956	276,477	353,699	670,750	927,899	2,359,000	2,228,825	2,045,657
Earned:
Treaty reinsurance									1,408,995	1,397,409	1,338,663
Facultative reinsurance									307,351	330,472	345,252
Direct									823,641	852,256	656,974
Ceded									(290,822)	(333,248)	(347,834)
Net premiums earned	$ 540,399	$ 563,775	$ 573,723	$ 571,268	$ 543,300	$ 555,011	$ 572,688	$ 575,890	2,249,165	2,246,889	1,993,055
Eliminations
Written:
Treaty reinsurance									(26,673)	(42,718)	(53,457)
Facultative reinsurance									0	0	0
Direct									0	0	0
Ceded									26,673	42,718	53,457
Net premiums written									0	0	0
Earned:
Treaty reinsurance									(23,035)	(45,115)	(60,912)
Facultative reinsurance									0	0	0
Direct									0	0	0
Ceded									23,035	45,115	60,912
Net premiums earned									0	0	0
Operating Segments | Validus Re
Written:
Treaty reinsurance									1,111,054	1,126,759	1,118,532
Facultative reinsurance									0	0	0
Direct									0	0	0
Ceded									(111,564)	(149,088)	(163,678)
Net premiums written									999,490	977,671	954,854
Earned:
Treaty reinsurance									1,060,117	1,141,184	1,109,659
Facultative reinsurance									0	0	0
Direct									0	0	0
Ceded									(116,172)	(150,971)	(192,375)
Net premiums earned									943,945	990,213	917,284
Operating Segments | Talbot
Written:
Treaty reinsurance									146,296	133,273	149,079
Facultative reinsurance									293,741	325,311	334,898
Direct									530,665	560,251	617,793
Ceded									(175,729)	(198,896)	(192,211)
Net premiums written									794,973	819,939	909,559
Earned:
Treaty reinsurance									115,828	136,796	163,382
Facultative reinsurance									307,351	330,472	345,252
Direct									529,265	570,669	576,136
Ceded									(170,528)	(199,846)	(204,996)
Net premiums earned									781,916	838,091	879,774
Operating Segments | Western World Insurance Group, Inc
Written:
Treaty reinsurance									0	0	0
Facultative reinsurance									0	0	0
Direct									323,220	278,504	65,235
Ceded									(22,634)	(18,877)	(6,428)	[1]
Net premiums written									300,586	259,627	58,807	[1]
Earned:
Treaty reinsurance									0	0	0
Facultative reinsurance									0	0	0
Direct									294,376	281,587	80,838
Ceded									(21,144)	(22,937)	(7,842)
Net premiums earned									273,232	258,650	72,996	[1]
Operating Segments | AlphaCat & Consolidated Variable Interest Entities
Written:
Treaty reinsurance									270,402	176,126	126,785
Facultative reinsurance									0	0	0
Direct									0	0	0
Ceded									(6,451)	(4,538)	(4,348)
Net premiums written									263,951	171,588	122,437
Earned:
Treaty reinsurance									256,085	164,544	126,534
Facultative reinsurance									0	0	0
Direct									0	0	0
Ceded									(6,013)	(4,609)	(3,533)
Net premiums earned									$ 250,072	$ 159,935	$ 123,001
[1]	The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.

Reinsurance (Reinsurance recove

Reinsurance (Reinsurance recoverables by reinsurer) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Ceded Credit Risk [Line Items]
Allowance for reinsurance recoverable	$ 5,153	$ 4,997
Reinsurance Recoverable [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 465,668	$ 373,657
Percentage of total reinsurance recoverable	100.00%	100.00%
Reinsurance Recoverable [Member] | A Minus Or Better Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 461,369	$ 368,638
Percentage of total reinsurance recoverable	99.10%	98.70%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 395,308	$ 303,108
Percentage of total reinsurance recoverable	84.90%	81.10%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Lloyds Syndicates [Member] | A (plus) [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 84,419	$ 66,356
Percentage of total reinsurance recoverable	18.20%	17.80%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Swiss Re [Member] | AA- [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 84,044	$ 83,048
Percentage of total reinsurance recoverable	18.10%	22.20%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Fully Collateralized [Member] | NR [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 83,088
Percentage of total reinsurance recoverable	17.80%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Hannover Re [Member] | AA- [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 50,603	$ 43,765
Percentage of total reinsurance recoverable	10.90%	11.70%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Everest Re [Member] | A (plus) [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 36,912	$ 43,060
Percentage of total reinsurance recoverable	7.90%	11.50%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Munich Re [Member] | AA- [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 18,214	$ 18,707
Percentage of total reinsurance recoverable	3.90%	5.00%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Transatlantic Re [Member] | A (plus) [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 10,593	$ 11,923
Percentage of total reinsurance recoverable	2.30%	3.20%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Hamilton Re [Member] | A- Rating [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 10,343	$ 10,898
Percentage of total reinsurance recoverable	2.20%	2.90%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | Toa Re [Member] | A (plus) [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 9,510	$ 6,330
Percentage of total reinsurance recoverable	2.00%	1.70%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | National Indemnity Company [Member] | AA (plus) [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 7,582	$ 10,293
Percentage of total reinsurance recoverable	1.60%	2.80%
Reinsurance Recoverable [Member] | Top 10 reinsurers [Member] | XL Re [Member] | A (plus) [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable		$ 8,728
Percentage of total reinsurance recoverable		2.30%
Reinsurance Recoverable [Member] | Other Reinsurers Balances Greater Than One Million Dollars [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 66,944	$ 61,222
Percentage of total reinsurance recoverable	14.40%	16.40%
Reinsurance Recoverable [Member] | Other Reinsurers Balances Less Than One Million Dollars [Member]
Ceded Credit Risk [Line Items]
Reinsurance recoverable	$ 3,416	$ 9,327
Percentage of total reinsurance recoverable	0.70%	2.50%

Share capital (Preferred shares

Share capital (Preferred shares) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Proportionate Interest of Series A Preference Shares, Per Depositary Share	0.10%
Preferred shares issued at beginning of year	0
Preferred shares issued	0	639	1,380
Preferred shares issued at end of year	6,000	0
Net proceeds on issuance of preferred shares	$ 144,852	$ 0	$ 0
Series A Preferred Stock
Class of Stock [Line Items]
Preferred shares issued at beginning of year	0
Preferred shares issued	6,000
Preferred shares issued at end of year	6,000	0
Preferred Stock, Dividend Rate, Percentage	5.875%
Preferred Stock, Par or Stated Value Per Share	$ 0.175
Preferred Stock, Liquidation Preference Per Share	$ 25,000
Depositary Share Equivalent
Class of Stock [Line Items]
Preferred shares issued at end of year	6,000,000
Preferred Stock, Liquidation Preference Per Share	$ 25
On or after June 15, 2021 | Series A Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Redemption Price Per Share	25,000
On or after June 15, 2021 | Depositary Share Equivalent
Class of Stock [Line Items]
Preferred Stock, Redemption Price Per Share	25
Prior to redemption if change in law or capital disqualification event | Series A Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Redemption Price Per Share	25,000
Prior to redemption if change in law or capital disqualification event | Depositary Share Equivalent
Class of Stock [Line Items]
Preferred Stock, Redemption Price Per Share	25
Prior to redemption date
Class of Stock [Line Items]
Preferred Stock, Redemption Price Per Share	26
Prior to redemption date | Series A Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Redemption Price Per Share	$ 26,000

Share capital (Summary of commo

Share capital (Summary of common shares issued and outstanding) (Details) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of common shares issued and outstanding
Common shares issued, beginning balance	160,570,772	155,554,224	154,488,497
Options exercised	30,530	782,465	412,656
Warrants exercised	0	3,593,715
Direct issuance of common stock	0	639	1,380
Common shares issued, ending balance	161,279,976	160,570,772	155,554,224
Treasury shares, ending balance	(82,147,724)	(77,670,155)	(71,684,379)
Common shares outstanding, ending balance	79,132,252	82,900,617	83,869,845
Restricted Stock [Member]
Summary of common shares issued and outstanding
Vested, net of shares withheld	612,100	614,945	615,659
Restricted share units [Member]
Summary of common shares issued and outstanding
Vested, net of shares withheld	18,486	13,260	10,265
Performance Shares [Member]
Summary of common shares issued and outstanding
Vested, net of shares withheld	48,088	11,524	25,767

Share capital (Narrative) (Deta

Share capital (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	Feb. 03, 2015	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Common Stock Issued and Outstanding [Line Items]
Authorized Share Capital		571,428,571				571,428,571				571,428,571	571,428,571
Common shares, par value		$ 0.175				$ 0.175				$ 0.175	$ 0.175
Common Stock, Voting Rights										one vote per share
Maximum Percent Of Outstanding Common Shares Controlled Contingent Under Voting Rights										9.09%
Stock repurchase program, authorized amount	$ 750,000
Share repurchase program cumulative aggregrate purchase value	$ 2,274,401									$ 2,704,406
Share repurchase program, cumulative shares repurchased										80,508,849
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 319,995								$ 319,995
Class of Warrant or Right, Outstanding		0								0
Warrants exercised										0	3,593,715
Cash dividends declared per share		$ 0.35	$ 0.35	$ 0.35	$ 0.35	0.32	$ 0.32	$ 0.32	$ 0.32	$ 1.40	$ 1.28	$ 1.20
Common shares
Schedule of Common Stock Issued and Outstanding [Line Items]
Cash dividends declared per share		0.35	0.35	$ 0.35	$ 0.35	$ 0.32	$ 0.32	$ 0.32	$ 0.32
Series A Preferred Stock
Schedule of Common Stock Issued and Outstanding [Line Items]
Cash dividends declared per share		$ 0.3671875	$ 0.3753472
Warrant [Member]
Schedule of Common Stock Issued and Outstanding [Line Items]
Number of warrants exercised during period										5,154,077
Warrants Expired During the Period										20,037

Stock plans (Options activity)

Stock plans (Options activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Options Activities
Options outstanding, beginning balance (in shares)	65,401	1,160,057	1,572,713
Options exercised during period (in shares)	(39,265)	(1,094,656)	(412,656)
Options outstanding, ending balance (in shares)	26,136	65,401	1,160,057
Weighted Average Grant Date Fair Value
Weighted average grant date fair value, beginning balance (in dollars per share)	$ 7.74	$ 7.12	$ 6.66
Weighted average grant date fair value, options exercised (in dollars per share)	8.37	7.09	5.36
Weighted average grant date fair value, ending balance (in dollars per share)	6.78	7.74	7.12
Weighted Average Grant Date Exercise Price
Weighted average grant date exercise price, beginning balance (in dollars per share)	20.17	17.74	18.88
Weighted average grant date exercise price, options exercised (in dollars per share)	17.96	17.60	22.07
Weighted average grant date exercise price, ending balance (in dollars per share)	$ 23.48	$ 20.17	$ 17.74
Total intrinsic value	$ 1,260	$ 26,367	$ 7,459
Company proceeds received	277	6,277	$ 9,107
Intrinsic value of options outstanding	$ 831	$ 1,740

Stock plans (Other awards activ

Stock plans (Other awards activity) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restricted Stock [Member]
Activities
Beginning balance	2,739,446	2,858,711	2,684,745
Granted	564,345	724,357	1,051,348
Vested	(796,716)	(788,758)	(797,446)
Forfeited	(37,093)	(54,864)	(79,936)
Ending balance	2,469,982	2,739,446	2,858,711
Share Based Payment Award Other Than Options Nonvested Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, beginning balance	$ 38.25	$ 35.81	$ 33.74
Weighted average grant date fair value, granted	48.83	43.67	37.81
Weighted average grant date fair value, vested	37.40	34.41	31.44
Weighted average grant date fair value, forfeited	41.27	38.14	36.09
Weighted average grant date fair value, ending balance	$ 40.89	$ 38.25	$ 35.81
Restricted share units [Member]
Activities
Beginning balance	114,337	103,484	66,518
Granted	27,609	28,057	53,025
Vested	(23,982)	(19,455)	(18,325)
Issued in lieu of cash dividends	3,182	3,143	2,266
Forfeited	(8,338)	(892)	0
Ending balance	112,808	114,337	103,484
Share Based Payment Award Other Than Options Nonvested Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, beginning balance	$ 38.47	$ 36.54	$ 33.74
Weighted average grant date fair value, granted	50.03	42.91	38.10
Weighted average grant date fair value, vested	38.18	34.58	30.71
Weighted average grant date fair value, issued in lieu of cash dividends	39.36	37.53	35
Weighted average grant date fair value, forfeited	44.34	35.42	0
Weighted average grant date fair value, ending balance	$ 40.95	$ 38.47	$ 36.54
Performance Shares [Member]
Activities
Beginning balance	172,594	106,369	101,820
Granted	125,290	81,569	52,639
Vested	(57,581)	(15,344)	(32,746)
Conversion adjustment	45,517	0	(15,344)
Ending balance	285,820	172,594	106,369
Share Based Payment Award Other Than Options Nonvested Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, beginning balance	$ 40.70	$ 36.03	$ 33.56
Weighted average grant date fair value, granted	48.75	45.03	37.33
Weighted average grant date fair value, vested	36.11	31.38	32.62
Weighted average grant date fair value, conversion adjustment	36.82	0	31.38
Weighted average grant date fair value, ending balance	$ 44.53	$ 40.70	$ 36.03

Stock plans (Components of shar

Stock plans (Components of share compensation expenses) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Total share compensation expenses
Share compensation expenses	$ 10,442	$ 10,501	$ 10,727	$ 11,237	$ 10,062	$ 9,983	$ 9,242	$ 9,054	$ 42,907	$ 38,341	$ 33,073
Restricted share awards [Member]
Total share compensation expenses
Share compensation expenses									36,887	35,386	31,335
Restricted share units [Member]
Total share compensation expenses
Share compensation expenses									1,285	1,160	876
Performance Shares [Member]
Total share compensation expenses
Share compensation expenses									$ 4,735	$ 1,795	$ 862

Stock plans (Narrative) (Detail

Stock plans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock plans (other details)
Number of shares reserved for issuance under the LTIP and STIP	2,753,292								2,753,292
Remaining number of shares reserved for issuance	1,251,411								1,251,411
Share compensation expenses	$ 10,442	$ 10,501	$ 10,727	$ 11,237	$ 10,062	$ 9,983	$ 9,242	$ 9,054	$ 42,907	$ 38,341	$ 33,073
Intrinsic value of options outstanding	831				1,740				831	1,740
Tax benefit from share compensation expenses									1,869	3,436	1,610
Net windfall taxes on vestings and exercises of stock options during the period									$ 1,203	906	3,513
Options [Member]
Stock plans (other details)
Life of options									10 years
Restricted share awards [Member]
Stock plans (other details)
Share compensation expenses									$ 36,887	35,386	31,335
Unrecognized share compensation expenses	58,804				69,143				$ 58,804	$ 69,143
Weighted average period of recognizing share based compensation expenses									2 years 3 months 3 days	2 years 4 months 24 days
Restricted share units [Member]
Stock plans (other details)
Share compensation expenses									$ 1,285	$ 1,160	876
Unrecognized share compensation expenses	2,542				2,790				$ 2,542	$ 2,790
Weighted average period of recognizing share based compensation expenses									2 years 6 months 21 days	2 years 7 months
Performance Shares [Member]
Stock plans (other details)
Share compensation expenses									$ 4,735	$ 1,795	$ 862
Unrecognized share compensation expenses	$ 6,902				$ 4,011				$ 6,902	$ 4,011
Weighted average period of recognizing share based compensation expenses									2 years 21 days	2 years 1 month 6 days
Performance Share Awards Performance Period									3 years

Retirement and pension plans (S

Retirement and pension plans (Summary of assumptions used in calculations) (Details) - Defined benefit plans	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Assumptions used to determine net periodic pension expense:
Discount rate	3.50%	2.75%
Increase in compensation levels rate	5.00%	5.00%
Assumptions used to determine benefit obligations:
Discount rate	4.00%	4.00%
Increase in compensation levels rate	5.00%	5.00%

Retirement and pension plans (C

Retirement and pension plans (Change in projected benefit obligation, plan assets, and funded status of plan) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Amounts recognized in the balance sheet:
Net amount recognized in accounts payable and accrued expenses	$ (16,979)	$ (15,722)
Defined benefit plans
Change in benefit obligation:
Projected benefit obligation, beginning of period	15,722	16,493
Service cost	1,026	1,024
Interest cost	594	434
Actuarial losses (gains)	1,473	(46)
Benefit payments	(98)	(98)
Settlements	(1,738)	(2,085)
Projected benefit obligation, end of period	16,979	15,722
Change in plan assets:
Fair value of plan assets, beginning of period	0
Employer contributions	1,836	2,186
Benefit payments	(98)	(98)
Settlements	(1,738)	(2,088)
Fair value of plan assets, end of period	0	0
Funded status, end of period	(16,979)	(15,722)
Amounts recognized in the balance sheet:
Net amount recognized in accounts payable and accrued expenses	(16,979)	(15,722)
Amounts recognized in accumulated other comprehensive loss consist of
Net loss (gain)	226	(517)
Prior service credit	6	4
Net amount recognized	232	(513)
Summary of projected benefit obligation, accumulated benefit obligation and fair value of plan assets:
Projected benefit obligation	16,979	15,722
Accumulated benefit obligation	13,480	13,308
Fair value of plan assets	$ 0	$ 0

Retirement and pension plans111

Retirement and pension plans (Components of net periodic pension expense) (Details) - Defined benefit plans - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,026	$ 1,024
Interest cost	594	434
Amortization of prior service cost	(2)	(2)
Amortization of net loss	374	312
Net periodic benefit cost	1,992	1,768
Settlement loss	356	484
Net periodic pension expense	$ 2,348	$ 2,252

Retirement and pension plans (O

Retirement and pension plans (Other changes recognized in other comprehensive income) (Details) - Defined benefit plans - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain)	$ 1,473	$ (43)
Amortization of loss	(374)	(312)
Amortization of prior service cost	2	2
Settlement loss	(356)	(484)
Total recognized in other comprehensive loss	745	(837)
Total recognized in net pension expense and other comprehensive loss (before tax effects)	3,093	$ 1,415
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year	$ 2

Retirement and pension plans (E

Retirement and pension plans (Estimated future benefit payments, fiscal year maturity) (Details) - Defined benefit plans - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
2,017	$ 2,740
2,018	7,072
2,019	92
2,020	2,665
2,021	83
2022-2026	5,449
Total benefit payments required	18,101
Employer benefit payments/settlements for current year	$ 1,836	$ 2,183

Retirement and pension plans (D

Retirement and pension plans (Defined contribution plans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined contribution plan
Defined contribution retirement plan expense	$ 13,419	$ 13,684	$ 10,606

Debt and financing arrangeme115

Debt and financing arrangements (Summary of outstanding debentures and senior notes payable) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Debentures payable	$ 537,226	$ 537,668
Debt instrument, commitment	250,000	250,000
Unamortized debt issuance costs	(4,638)	(4,839)
Senior notes payable	245,362	245,161
Debentures and senior notes payable	782,588	782,829
Junior Subordinated Deferrable Debentures Two Thousand Six [Member]
Debt Instrument [Line Items]
Debentures payable	150,000	150,000
Debt instrument, commitment	150,000
Junior Subordinated Deferrable Debentures Two Thousand Seven [Member]
Debt Instrument [Line Items]
Debentures payable	139,800	139,800
Debt instrument, commitment	200,000
Flagstone 2007 Due July 30 2037 [Member]
Debt Instrument [Line Items]
Debentures payable	113,750	113,750
Debt instrument, commitment	88,750
Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Debt Instrument [Line Items]
Debentures payable	133,676	$ 134,118
Debt instrument, commitment	$ 133,676

Debt and financing arrangeme116

Debt and financing arrangements (Credit and other facilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
Credit facility, commitment	$ 690,000	$ 700,000
Letters of credit issued and outstanding	265,039	479,088
Five-year unsecured credit facility [Member]
Line of Credit Facility [Line Items]
Credit facility, commitment	85,000	85,000
Letters of credit issued and outstanding	0	0
Five-year syndicated secured credit facility [Member]
Line of Credit Facility [Line Items]
Credit facility, commitment	300,000	300,000
Letters of credit issued and outstanding	90,252	235,540
$24,000 secured bi-lateral letter of credit facility
Line of Credit Facility [Line Items]
Credit facility, commitment	24,000	24,000
Letters of credit issued and outstanding	4,553	10,543
AlphaCat Re secured letter of credit facility
Line of Credit Facility [Line Items]
Credit facility, commitment	20,000	30,000
Letters of credit issued and outstanding	20,000	30,000
IPC bi-lateral facility
Line of Credit Facility [Line Items]
Credit facility, commitment	25,000	25,000
Letters of credit issued and outstanding	5,842	9,241
$236,000 Flagstone bi-lateral facility
Line of Credit Facility [Line Items]
Credit facility, commitment	236,000	236,000
Letters of credit issued and outstanding	$ 144,392	$ 193,764

Debt and financing arrangeme117

Debt and financing arrangements (Summary of key terms of notes and debentures) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Amount		$ 250,000	$ 250,000
2006 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Issuance date		Jun. 15, 2006
Amount		$ 150,000
Maturity date		Jun. 15, 2036
Interest payments due		Quarterly
Interest rate term		5 years
2006 Junior Subordinated Deferrable Debentures [Member] | LIBOR
Debt Instrument [Line Items]
Spread on LIBOR		3.55%
Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Debt Instrument [Line Items]
Issuance date		Aug. 23, 2006
Amount		$ 133,676
Maturity date		Sep. 15, 2036
Interest payments due		Quarterly
2007 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Issuance date		Jun. 21, 2007
Amount		$ 200,000
Maturity date		Jun. 15, 2037
Interest payments due		Quarterly
Interest rate term		5 years
2007 Junior Subordinated Deferrable Debentures [Member] | LIBOR
Debt Instrument [Line Items]
Spread on LIBOR		2.95%
Flagstone 2007 Due July 30 2037 [Member]
Debt Instrument [Line Items]
Issuance date		Jun. 8, 2007
Amount		$ 88,750
Maturity date		Jul. 30, 2037
Interest payments due		Quarterly
Flagstone 2007 Debt Due September 15 2037 [Member]
Debt Instrument [Line Items]
Issuance date		Sep. 20, 2007
Amount		$ 25,000
Maturity date		Sep. 15, 2037
Interest payments due		Quarterly
2010 Senior Notes due 2040 [Member]
Debt Instrument [Line Items]
Issuance date		Jan. 26, 2010
Amount		$ 250,000
Maturity date		Jan. 26, 2040
Interest payments due		Semi-annually in arrears
Debt Information At Issuance [Member] | 2006 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Fixed interest rate	[1]	9.069%
Debt Information At Issuance [Member] | Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member] | LIBOR
Debt Instrument [Line Items]
Spread on LIBOR	[2]	3.54%
Debt Information At Issuance [Member] | 2007 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Fixed interest rate	[3]	8.48%
Debt Information At Issuance [Member] | Flagstone 2007 Due July 30 2037 [Member] | LIBOR
Debt Instrument [Line Items]
Spread on LIBOR	[2]	3.00%
Debt Information At Issuance [Member] | Flagstone 2007 Debt Due September 15 2037 [Member] | LIBOR
Debt Instrument [Line Items]
Spread on LIBOR	[2]	3.10%
Debt Information At Issuance [Member] | 2010 Senior Notes due 2040 [Member]
Debt Instrument [Line Items]
Fixed interest rate	[4]	8.875%
Debt Outstanding [Member] | 2006 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Effective interest rate	[5]	5.831%
Debt Outstanding [Member] | Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Debt Instrument [Line Items]
Effective interest rate	[5]	6.463%
Debt Outstanding [Member] | 2007 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Effective interest rate	[5]	5.18%
Debt Outstanding [Member] | Flagstone 2007 Due July 30 2037 [Member]
Debt Instrument [Line Items]
Effective interest rate	[5]	5.90%
Debt Outstanding [Member] | Flagstone 2007 Debt Due September 15 2037 [Member]
Debt Instrument [Line Items]
Effective interest rate	[5]	5.983%
Debt Outstanding [Member] | 2010 Senior Notes due 2040 [Member]
Debt Instrument [Line Items]
Fixed interest rate	[4]	8.875%
[1]	Fixed interest rate for 5 years, floating interest rate of three-month LIBOR plus 3.550% thereafter, reset quarterly.
[2]	Floating interest rate of three-month LIBOR plus amount stated, reset quarterly.
[3]	Fixed interest rate for 5 years, floating interest rate of three-month LIBOR plus 2.950% thereafter, reset quarterly.
[4]	Fixed interest rate.
[5]	Fixed interest rate as a result of interest rate swap contracts entered into by the Company.

Debt and financing arrangeme118

Debt and financing arrangements (Investments pledged as collateral) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financial Instruments Owned and Pledged as Collateral [Line Items]
Investments pledged as collateral	$ 442,184	$ 826,535
Five-year syndicated secured credit facility [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Investments pledged as collateral	157,597	370,909
$24,000 secured bi-lateral letter of credit facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Investments pledged as collateral	48,097	47,607
AlphaCat Re secured letter of credit facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Investments pledged as collateral	20,032	30,153
$236,000 Flagstone bi-lateral facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Investments pledged as collateral	$ 216,458	$ 377,866

Debt and financing arrangeme119

Debt and financing arrangements (Components of finance expenses) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Components of financial expenses
Finance expenses		$ 14,630	$ 14,521	$ 14,166	$ 15,203	$ 16,581	$ 18,512	$ 18,682	$ 20,967	$ 58,520	$ 74,742	$ 68,324
2006 Junior Subordinated Deferrable Debentures [Member]
Components of financial expenses
Finance expenses										8,893	8,868	8,868
2007 Junior Subordinated Deferrable Debentures [Member]
Components of financial expenses
Finance expenses										7,362	7,341	7,341
Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Components of financial expenses
Finance expenses										9,028	8,989	9,001
Flagstone 2007 Junior Subordinated Deferrable Interest Notes [Member]
Components of financial expenses
Finance expenses										7,100	7,123	7,129
2010 Senior Notes due 2040 [Member]
Components of financial expenses
Finance expenses										22,388	22,388	22,388
Credit Facilities [Member]
Components of financial expenses
Finance expenses										2,060	6,006	5,516
Bank charges, Talbot FAL facility and other charges
Components of financial expenses
Finance expenses	[1]									504	4,592	4,536
AlphaCat Fees [Member]
Components of financial expenses
Finance expenses	[2]									$ 1,185	$ 9,435	$ 3,545
[1]	On November 30, 2015, the Company terminated its Talbot FAL Facility provided and arranged by Lloyds Bank plc and ING Bank N.V., London Branch.
[2]	Includes finance expenses incurred by AlphaCat Managers in relation to fund raising for the AlphaCat sidecars, the AlphaCat ILS funds and AlphaCat direct.

Debt and financing arrangeme120

Debt and financing arrangements (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Debt and financing arrangements [Line Items]
Amount	$ 250,000	$ 250,000
Debentures payable	537,226	537,668
Credit facility, commitment	690,000	700,000
Letters of credit issued and outstanding	265,039	479,088
Debentures and senior notes payable	782,588	782,829
Investments pledged as collateral	$ 442,184	826,535
Five Year Credit Facilities [Member]
Debt and financing arrangements [Line Items]
Percent of consolidated net income quarterly increase under covenant	25.00%
Percent of any net proceeds from issuance of common shares	50.00%
Ratio consolidated total debt to net worth under covenant	0.35:1.00
Minimum level of consolidated net worth	$ 2,600,000
Five-year syndicated secured credit facility [Member]
Debt and financing arrangements [Line Items]
Letter of credit facility period	5 years
Line of credit facility initiation date	Dec. 9, 2015
Credit facility, commitment	$ 300,000	300,000
Letters of credit issued and outstanding	90,252	235,540
Aggregate commitments, maximum	400,000
Investments pledged as collateral	$ 157,597	370,909
Five-year unsecured credit facility [Member]
Debt and financing arrangements [Line Items]
Letter of credit facility period	5 years
Line of credit facility initiation date	Dec. 9, 2015
Credit facility, commitment	$ 85,000	85,000
Letters of credit issued and outstanding	0	0
Aggregate commitments, maximum	150,000
IPC bi-lateral facility
Debt and financing arrangements [Line Items]
Credit facility, commitment	25,000	25,000
Letters of credit issued and outstanding	5,842	9,241
$24,000 secured bi-lateral letter of credit facility
Debt and financing arrangements [Line Items]
Credit facility, commitment	24,000	24,000
Letters of credit issued and outstanding	4,553	10,543
Investments pledged as collateral	48,097	47,607
AlphaCat Re secured letter of credit facility
Debt and financing arrangements [Line Items]
Credit facility, commitment	20,000	30,000
Letters of credit issued and outstanding	20,000	30,000
Investments pledged as collateral	20,032	30,153
$236,000 Flagstone bi-lateral facility
Debt and financing arrangements [Line Items]
Credit facility, commitment	236,000	236,000
Letters of credit issued and outstanding	144,392	193,764
Investments pledged as collateral	216,458	$ 377,866
2010 Senior Notes due 2040 [Member]
Debt and financing arrangements [Line Items]
Amount	$ 250,000
Junior Subordinated Deferrable Debentures[Member]
Debt and financing arrangements [Line Items]
Debt Instrument Redemption Period Duration	5 years
Debentures payable	$ 537,226
Minimum
Debt and financing arrangements [Line Items]
Debt Instrument Redemption Required Notice Period	30 days
Maximum
Debt and financing arrangements [Line Items]
Debt Instrument Redemption Required Notice Period	60 days

Income taxes (Components of tax

Income taxes (Components of tax expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosures [Line Items]
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors	$ 23,103	$ 136,929	$ 123,976	$ 206,846	$ 96,964	$ 104,298	$ 89,162	$ 190,170	$ 490,854	$ 480,594	$ 559,338
Components of income tax expense:
U.S.									2,042	739	21,257
Non-U.S.									711	6,028	26,179
Total current income tax expense									2,753	6,767	47,436
U.S.									(3,487)	1,360	(24,998)
Non-U.S.									(18,995)	(1,751)	(22,283)
Total deferred income tax benefit									(22,482)	(391)	(47,281)
U.S.									(1,445)	2,099	(3,741)
Non-U.S.									(18,284)	4,277	3,896
Total income tax (benefit) expense	$ (21,147)	$ 1,830	$ 1,706	$ (2,118)	$ (756)	$ 2,018	$ 2,549	$ 2,565	(19,729)	6,376	155
Bermuda
Income Tax Disclosures [Line Items]
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors									447,257	470,454	518,476
United Kingdom
Income Tax Disclosures [Line Items]
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors									4,308	13,621	10,824
United States
Income Tax Disclosures [Line Items]
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors									4,038	(4,176)	(11,752)
Switzerland
Income Tax Disclosures [Line Items]
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors									(1,084)	2,276	9,941
Canada
Income Tax Disclosures [Line Items]
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors									2,599	493	2,773
Other tax jurisdictions
Income Tax Disclosures [Line Items]
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors									$ 33,736	$ (2,074)	$ 29,076

Income taxes (Reconciliation of

Income taxes (Reconciliation of effective tax rate) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Bermuda tax rate									0.00%	0.00%	0.00%
Tax charge by jurisdiction
Expected tax expense at Bermuda statutory rate of 0%									$ 0	$ 0	$ 0
Foreign tax rate differential									11,394	6,462	7,993
Changes in valuation allowance									(36,990)	9,830	(7,284)
Tax exempt income and expenses not deductible									(1,960)	393	(6,055)
Share compensation tax windfall									1,203	906	3,513
Impact of enacted changes in tax rates									8,931	69	250
Prior years tax adjustments									(5,199)	(12,272)	666
Actual income tax (benefit) expense									2,892	988	1,072
Total income tax (benefit) expense	$ (21,147)	$ 1,830	$ 1,706	$ (2,118)	$ (756)	$ 2,018	$ 2,549	$ 2,565	$ (19,729)	$ 6,376	$ 155

Income taxes (Components of net

Income taxes (Components of net deferred tax liability) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax asset
Tax losses carried forward	$ 116,416	$ 167,929
Deferred compensation	6,915	7,504
Deferred Tax Assets, Tax Deferred Expense, Other	2,039	2,047
Tax credits carried forward	5,469	2,761
Discounting of loss reserves	9,938	11,882
Unearned premiums reserve	6,647	4,291
Pension	5,943	5,503
Lloyd’s underwriting loss deductible in future periods	581	47
Other	4,943	4,111
Deferred tax asset, gross of valuation allowance	158,891	206,075
Valuation allowance	(98,065)	(167,929)
Net deferred tax asset	60,826	38,146
Deferred tax liability
Deferred acquisition costs	4,633	1,989
Intangibles	7,583	8,111
Unrealized appreciation on investments	3,179	7,073
Properties and fixed assets	2,593	2,044
Other	2,640	1,115
Deferred tax liability	20,628	20,332
Net deferred tax asset	$ 40,198	$ 17,814

Income taxes (Movement in tax c

Income taxes (Movement in tax carryforwards and valuation allowance) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Tax Credit Carryforward [Line Items]
Balance at beginning of year	$ 167,929
Balance at beginning of year	(167,929)
Balance at end of year	116,416
Balance at end of year	(98,065)
Deferred Tax Asset on Tax Losses Carried Forward
Tax Credit Carryforward [Line Items]
Balance at beginning of year	167,929
Movement due to use of tax losses carried forward	(10,990)
Movement due to provision to return adjustments	1,108
Movement due to changes in enacted tax rates	(8,757)
Movement due to change in assessment of deferred tax asset recoverability	0
Forfeiture of tax losses carried forward	(32,927)
Other	53
Balance at end of year	116,416
Valuation Allowance
Tax Credit Carryforward [Line Items]
Balance at beginning of year	(167,929)
Movement due to use of tax losses carried forward	10,990
Movement due to provision to return adjustments	(1,108)
Movement due to changes in enacted tax rates	8,757
Movement due to change in assessment of deferred tax asset recoverability	18,351
Forfeiture of tax losses carried forward	32,927
Other	(53)
Balance at end of year	(98,065)
Luxembourg | Deferred Tax Asset on Tax Losses Carried Forward
Tax Credit Carryforward [Line Items]
Movement due to use of tax losses carried forward	6,722
Movement due to changes in enacted tax rates	(8,757)
Forfeiture of tax losses carried forward	18,438
Luxembourg | Valuation Allowance
Tax Credit Carryforward [Line Items]
Movement due to change in assessment of deferred tax asset recoverability	18,351
United States | Deferred Tax Asset on Tax Losses Carried Forward
Tax Credit Carryforward [Line Items]
Movement due to use of tax losses carried forward	3,066
Singapore | Deferred Tax Asset on Tax Losses Carried Forward
Tax Credit Carryforward [Line Items]
Movement due to use of tax losses carried forward	1,202
Switzerland | Deferred Tax Asset on Tax Losses Carried Forward
Tax Credit Carryforward [Line Items]
Forfeiture of tax losses carried forward	$ 14,489

Income taxes (Loss carryforward

Income taxes (Loss carryforwards) (Details) $ in Thousands	Dec. 31, 2016USD ($)
United States
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	$ 11,195
Loss Carryforwards, Tax Effect	3,918
Switzerland
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	157,512
Loss Carryforwards, Tax Effect	33,078
Luxembourg
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	300,121
Loss Carryforwards, Tax Effect	78,310
Singapore
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	11,090
Loss Carryforwards, Tax Effect	$ 1,109

Accumulated other comprehens126

Accumulated other comprehensive loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Loss [Line Items]
Balance, net of tax, at beginning of year	$ 3,793,637	$ 3,878,860
Balance, net of tax, at end of year	4,004,268	3,793,637	$ 3,878,860
Accumulated other comprehensive loss
Accumulated Other Comprehensive Loss [Line Items]
Balance, net of tax, at beginning of year	(12,569)	(8,556)	(617)
Net current period other comprehensive income (loss), net of tax	(10,647)	(4,013)	(7,939)
Balance, net of tax, at end of year	(23,216)	(12,569)	(8,556)
Foreign currency translation adjustment
Accumulated Other Comprehensive Loss [Line Items]
Balance, net of tax, at beginning of year	(11,834)	(8,118)	(617)
Net current period other comprehensive income (loss), net of tax	(10,440)	(3,716)	(7,501)
Balance, net of tax, at end of year	(22,274)	(11,834)	(8,118)
Minimum pension liability
Accumulated Other Comprehensive Loss [Line Items]
Balance, net of tax, at beginning of year	334	(210)	0
Net current period other comprehensive income (loss), net of tax	(484)	544	(210)
Balance, net of tax, at end of year	(150)	334	(210)
Cash flow hedge
Accumulated Other Comprehensive Loss [Line Items]
Balance, net of tax, at beginning of year	(1,069)	(228)	0
Net current period other comprehensive income (loss), net of tax	277	(841)	(228)
Balance, net of tax, at end of year	$ (792)	$ (1,069)	$ (228)

Commitments and contingencie127

Commitments and contingencies (Significant brokers) (Details) - Customer Concentration Risk - Gross Premiums Written	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Marsh & McLennan
Concentration Risk [Line Items]
Concentration Risk, Percentage	28.80%	28.20%	28.50%
Aon Benfield Group Ltd
Concentration Risk [Line Items]
Concentration Risk, Percentage	16.20%	15.50%	20.00%
Willis Group Holdings Ltd
Concentration Risk [Line Items]
Concentration Risk, Percentage	14.10%	14.30%	18.00%

Commitments and contingencie128

Commitments and contingencies (Future minimum lease payments) (Details) - Office Space And Office Equipment - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Future minimum lease commitments are as follows:
2,017	$ 11,878
2,018	12,214
2,019	11,958
2,020	11,059
2,021	10,316
2022 and thereafter	46,418
Total	103,843
Total rent expense with respect to operating leases:
Rent expense	$ 9,761	$ 10,143	$ 10,540

Commitments and contingencie129

Commitments and contingencies (Lloyd's syndicate) (Details) - 12 months ended Dec. 31, 2016 - Lloyd's Syndicate 1183 £ in Thousands, $ in Thousands	USD ($)	GBP (£)
Funds at Lloyd's and Lloyd's Central Fund
Maximum premium levies assessable, percent	3.00%	3.00%
Estimated underwriting capacity | £		£ 600,000
Exchange rate	£1 equals $1.23	£1 equals $1.23
Maximum premium levies assessable, amount	$ 22,140
2017 Underwriting Year
Components Of Required Capital [Abstract]
Required capital	583,600
2016 underwriting year
Components Of Required Capital [Abstract]
Required capital	$ 617,000

Commitments and contingencie130

Commitments and contingencies (Investment commitments) (Details) - USD ($) $ in Thousands	Dec. 30, 2016	Dec. 30, 2015	Dec. 29, 2014	Nov. 07, 2014	Oct. 02, 2014	Dec. 31, 2016	Dec. 31, 2015
Aquiline Capital Partners II GP Offshore Ltd
Related Party Transaction [Line Items]
Capital commitment						$ 50,000
Remaining commitment						1,700	$ 3,413
Fixed maturities commitment
Related Party Transaction [Line Items]
Other commitment						28,499	34,888
Investment commitment
Related Party Transaction [Line Items]
Contractual obligation						308,000	263,000
Remaining commitment						156,134	185,548
Aquiline Financial Services Fund III LP
Related Party Transaction [Line Items]
Capital commitment				$ 100,000
Remaining commitment						62,031	86,110
AlphaCat Fund A
Related Party Transaction [Line Items]
Capital commitment			$ 20,000
Remaining commitment						0	10,000
Fund B - initial investment
Related Party Transaction [Line Items]
Capital commitment		$ 25,000
Remaining commitment						0	9,536
AlphaCat Fund B
Related Party Transaction [Line Items]
Capital commitment	$ 25,000
Remaining commitment						10,000
Western World Insurance Group, Inc [Member] | Aquiline Capital Partners II GP Offshore Ltd
Related Party Transaction [Line Items]
Capital commitment					$ 10,000	10,000
Remaining commitment						$ 340	$ 683

Commitments and contingencie131

Commitments and contingencies (Other details) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Western World Insurance Group, Inc
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	$ 3,186	$ 3,108

Related party transactions (Det

Related party transactions (Details) - USD ($)	Nov. 07, 2014	Oct. 02, 2014	Dec. 20, 2011	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Group Ark Insurance Holdings Ltd
Related Party Transaction [Line Items]
Gross premiums written				$ 3,157,000	$ 2,718,000	$ 2,073,000
Premiums receivable				292,000	82,000
Reinsurance premiums ceded				40,000	24,000	126,000
Related Party Transaction Reinsurance Balances Payable				0	4,000
Related Party Transaction Loss Reserves Recoverable				798,000	790,000
Earned premium adjustments				3,115,000	2,833,000	1,982,000
Wellington Insurance Company [Member]
Related Party Transaction [Line Items]
Premiums receivable				666,000	0
Reinsurance premiums ceded						0
Related Party Transaction Reinsurance Balances Payable				2,860,000	0	0
Earned premium adjustments				$ 2,603,000	0
Conning Inc
Related Party Transaction [Line Items]
Investment management fees					841,000	1,125,000
Aquiline Capital Partners II GP Offshore Ltd
Related Party Transaction [Line Items]
Percentage of interest assumed				100.00%
Capital commitment				$ 50,000,000
Partnership fees incurred				843,000	1,519,000	410,000
Payments for (Proceeds from) Limited Partnership				$ (9,032,000)	6,093,000	12,468,000
Aquiline Financial Services Fund II LP
Related Party Transaction [Line Items]
Percentage of interest assumed				100.00%
Capital commitment		$ 10,000,000	$ 50,000,000
Aquiline Financial Services Fund III LP
Related Party Transaction [Line Items]
Capital commitment	$ 100,000,000
Partnership fees incurred				$ 2,031,000	1,814,000
Payments for (Proceeds from) Limited Partnership				23,873,000	$ 13,793,000	$ 0
Western World Insurance Group, Inc | Aquiline Capital Partners II GP Offshore Ltd
Related Party Transaction [Line Items]
Capital commitment		$ 10,000,000		$ 10,000,000

Earnings per share (Details)

Earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Basic earnings per share
Net income available to Validus common shareholders	$ 7,767	$ 89,844	$ 94,963	$ 166,810	$ 69,042	$ 66,650	$ 65,790	$ 173,411	$ 359,384	$ 374,893	$ 479,963
Less: Dividends declared on outstanding warrants									0	(3,566)	(6,208)
Net income allocated to Validus common shareholders									$ 359,384	$ 371,327	$ 473,755
Weighted average number of common shares outstanding									81,041,974	83,107,236	90,354,745
Basic earnings per share available to common shareholders	$ 0.10	$ 1.12	$ 1.16	$ 2.01	$ 0.84	$ 0.79	$ 0.77	$ 2.07	$ 4.43	$ 4.47	$ 5.24
Diluted earnings per share
Less: Dividends and distributions declared on outstanding warrants									$ 0	$ 0	$ 0
Income (loss) available (attributable) to common shareholders									$ 359,384	$ 374,893	$ 479,963
Weighted average number of common shares outstanding									81,041,974	83,107,236	90,354,745
Weighted average number of common shares outstanding, diluted									82,359,460	86,426,760	94,690,271
Earnings per diluted share available to common shareholders	$ 0.10	$ 1.11	$ 1.14	$ 1.98	$ 0.81	$ 0.78	$ 0.75	$ 1.98	$ 4.36	$ 4.34	$ 5.07
Earnings per share (Textuals) [Abstract]
Anti-dilutive securities excluded from the calculation of diluted earnings per share									133,810	167,417	199,740
Warrants [Member]
Diluted earnings per share
Weighted average number diluted shares outstanding adjustment									0	2,090,248	2,789,032
Options [Member]
Diluted earnings per share
Weighted average number diluted shares outstanding adjustment									28,196	151,867	745,561
Unvested restricted shares [Member]
Diluted earnings per share
Weighted average number diluted shares outstanding adjustment									1,289,290	1,077,409	800,933

Segment information (Details)

Segment information (Details) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)segments	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segments										4
Underwriting income
Gross premiums written		$ 339,454	$ 372,418	$ 764,042	$ 1,172,791	$ 309,605	$ 402,509	$ 726,168	$ 1,119,224	$ 2,648,705	$ 2,557,506	$ 2,358,865
Reinsurance premiums ceded		(40,635)	(45,006)	(36,229)	(167,835)	(33,128)	(48,810)	(55,418)	(191,325)	(289,705)	(328,681)	(313,208)
Net premiums written		298,819	327,412	727,813	1,004,956	276,477	353,699	670,750	927,899	2,359,000	2,228,825	2,045,657
Change in unearned premiums		241,580	236,363	(154,090)	(433,688)	266,823	201,312	(98,062)	(352,009)	(109,835)	18,064	(52,602)
Net premiums earned		540,399	563,775	573,723	571,268	543,300	555,011	572,688	575,890	2,249,165	2,246,889	1,993,055
Other insurance related income (loss)										2,961	6,113	3,472
Segmental revenues										2,252,126	2,253,002	1,996,527
Underwriting deductions
Losses and loss expenses		275,126	258,394	307,130	224,447	214,748	256,010	266,146	240,929	1,065,097	977,833	765,015
Policy acquisition costs		120,889	113,434	107,966	107,193	102,285	105,039	104,323	98,411	449,482	410,058	339,467
General and administrative expenses		77,955	82,443	89,688	86,208	98,563	96,886	84,025	84,235	336,294	363,709	329,362
Share compensation expenses		10,442	10,501	10,727	11,237	10,062	9,983	9,242	9,054	42,907	38,341	33,073
Total segmental deductions										1,893,780	1,789,941	1,466,917
Segmental income										358,346	463,061	529,610
Other items	[1]									1,829	(120,616)	(66,757)
Dividends on preferred shares		(2,203)	(2,252)	0	0	0	0	0	0	(4,455)	0	0
Net investment income		38,153	43,514	39,257	29,461	31,612	31,572	33,611	31,029	150,385	127,824	100,086
(Income) attributable to AlphaCat investors		(7,080)	(5,564)	(6,114)	(4,600)	(974)	(1,438)	0	0	(23,358)	(2,412)	0
Net (income) attributable to noncontrolling interests		(27,200)	(37,439)	(21,193)	(37,531)	(25,996)	(26,229)	(22,561)	(18,178)	(123,363)	(92,964)	(74,880)
Finance expenses		14,630	14,521	14,166	15,203	16,581	18,512	18,682	20,967	58,520	74,742	68,324
Tax benefit (expense)		21,147	(1,830)	(1,706)	2,118	756	(2,018)	(2,549)	(2,565)	19,729	(6,376)	(155)
Net realized gains on investments		9,220	4,397	2,724	(584)	(2,928)	(1,187)	2,244	4,169	15,757	2,298	14,917
Change in net unrealized gains (losses) on managed investments (a)		(67,460)	5,459	31,428	47,444	(34,862)	3,916	(34,676)	33,227	16,871	(32,395)	(2,842)
(Loss) income from investment affiliates		2,166	453	(589)	(4,113)	(1,261)	2,482	284	2,776	(2,083)	4,281	8,411
Foreign exchange gains		(901)	(766)	6,286	6,245	797	(2,592)	(2,671)	(4,265)	10,864	(8,731)	(12,181)
Transaction expenses										0	0	(8,096)	[2]
Net income available to Validus common shareholders		$ 7,767	$ 89,844	$ 94,963	$ 166,810	$ 69,042	$ 66,650	$ 65,790	$ 173,411	359,384	374,893	479,963
Operating Segments | Validus Re
Underwriting income
Gross premiums written										1,111,054	1,126,759	1,118,532
Reinsurance premiums ceded										(111,564)	(149,088)	(163,678)
Net premiums written										999,490	977,671	954,854
Change in unearned premiums										(55,545)	12,542	(37,570)
Net premiums earned										943,945	990,213	917,284
Other insurance related income (loss)										(55)	3,575	3,159
Segmental revenues										943,890	993,788	920,443
Underwriting deductions
Losses and loss expenses										411,488	457,976	307,290
Policy acquisition costs										181,040	166,387	141,670
General and administrative expenses										72,770	78,428	74,739
Share compensation expenses										11,034	10,350	9,739
Total segmental deductions										676,332	713,141	533,438
Segmental income										267,558	280,647	387,005
Validus share of segmental income										$ 267,558	$ 280,647	$ 387,005
Selected ratios:
Ratio of net to gross premiums written										90.00%	86.80%	85.40%
Losses and loss expenses ratio										43.60%	46.20%	33.50%
Policy acquisition costs ratio										19.20%	16.80%	15.50%
General and administrative expenses ratio	[3]									8.80%	9.00%	9.20%
Expense ratio										28.00%	25.80%	24.70%
Combined ratio										71.60%	72.00%	58.20%
Operating Segments | Talbot
Underwriting income
Gross premiums written										$ 970,702	$ 1,018,835	$ 1,101,770
Reinsurance premiums ceded										(175,729)	(198,896)	(192,211)
Net premiums written										794,973	819,939	909,559
Change in unearned premiums										(13,057)	18,152	(29,785)
Net premiums earned										781,916	838,091	879,774
Other insurance related income (loss)										455	851	1,095
Segmental revenues										782,371	838,942	880,869
Underwriting deductions
Losses and loss expenses										424,946	347,322	423,394
Policy acquisition costs										177,127	187,535	187,162
General and administrative expenses										134,479	155,306	150,828
Share compensation expenses										13,078	12,373	11,346
Total segmental deductions										749,630	702,536	772,730
Segmental income										32,741	136,406	108,139
Validus share of segmental income										$ 32,741	$ 136,406	$ 108,139
Selected ratios:
Ratio of net to gross premiums written										81.90%	80.50%	82.60%
Losses and loss expenses ratio										54.30%	41.40%	48.10%
Policy acquisition costs ratio										22.70%	22.40%	21.30%
General and administrative expenses ratio	[3]									18.90%	20.00%	18.40%
Expense ratio										41.60%	42.40%	39.70%
Combined ratio										95.90%	83.80%	87.80%
Operating Segments | AlphaCat
Underwriting income
Gross premiums written	[4]									$ 270,402	$ 176,126	$ 126,785
Third party management fees	[4]									18,771	19,661	18,667
Related party management fees	[4]									3,329	5,309	7,467
Segmental revenues	[4]									22,100	24,970	26,134
Underwriting deductions
General and administrative expenses	[4]									10,233	12,115	10,134
Share compensation expenses	[4]									249	580	501
Total segmental deductions	[4]									11,538	21,991	14,032
Segmental income	[4]									10,562	2,979	12,102
Net investment income	[4],[5]									20,579	19,176	21,485
Finance expenses	[4]									947	9,312	3,417
Tax benefit (expense)										(90)	0	0
Foreign exchange gains	[4]									(19)	16	20
Operating Segments | AlphaCat | AlphaCat Re & Master Fund
Underwriting deductions
Net investment income	[4],[5]									0	0	(1,377)
Operating Segments | AlphaCat | AlphaCat Sidecars
Underwriting income
Gross premiums written	[4]									(341)	45,755	50,023
Underwriting deductions
Net investment income	[4],[5]									607	5,504	10,525
Operating Segments | AlphaCat | AlphaCat ILS Funds - Lower Risk
Underwriting income
Gross premiums written	[4],[6]									112,222	91,363	52,264
Underwriting deductions
Net investment income	[4],[5],[6]									8,901	7,491	7,974
Operating Segments | AlphaCat | AlphaCat ILS Funds - Higher Risk
Underwriting income
Gross premiums written	[4],[6]									140,022	34,228	24,498
Underwriting deductions
Net investment income	[4],[5],[6]									7,471	8,428	8,754
Operating Segments | AlphaCat | BetaCat ILS Funds
Underwriting deductions
Net investment income	[4],[5]									3,623	1,702	(51)
Operating Segments | AlphaCat | PaCRe
Underwriting deductions
Net investment income	[4],[5]									(23)	(3,949)	(4,340)
Operating Segments | AlphaCat | AlphaCat Direct
Underwriting income
Gross premiums written	[4]									18,499	4,780	0
Operating Segments | AlphaCat & Consolidated Variable Interest Entities
Underwriting income
Gross premiums written										270,402	176,126	126,785
Reinsurance premiums ceded										(6,451)	(4,538)	(4,348)
Net premiums written										263,951	171,588	122,437
Change in unearned premiums										(13,879)	(11,653)	564
Net premiums earned										250,072	159,935	123,001
Other insurance related income (loss)										22,386	25,524	25,750
Segmental revenues										272,458	185,459	148,751
Underwriting deductions
Losses and loss expenses										44,851	657	(16,704)
Policy acquisition costs										26,905	16,327	11,584
General and administrative expenses										34,333	39,055	36,298
Share compensation expenses										249	580	501
Total segmental deductions										106,338	56,619	31,679
Segmental income										166,120	128,840	117,072
Other items	[1]									2,478	(17,967)	(12,891)
Dividends on preferred shares											0
Net investment income										9,264	6,658	4,286
(Income) attributable to AlphaCat investors										(23,358)	(2,412)
Net (income) attributable to noncontrolling interests										(123,363)	(92,964)	74,880
Validus share of segmental income	[4]									31,141	22,155	33,587
Operating Segments | Western World Insurance Group, Inc
Underwriting income
Gross premiums written										323,220	278,504	65,235	[7]
Reinsurance premiums ceded										(22,634)	(18,877)	(6,428)	[7]
Net premiums written										300,586	259,627	58,807	[7]
Change in unearned premiums										(27,354)	(977)	14,189	[7]
Net premiums earned										273,232	258,650	72,996	[7]
Other insurance related income (loss)										912	1,044	264	[7]
Segmental revenues										274,144	259,694	73,260	[7]
Underwriting deductions
Losses and loss expenses										183,812	171,878	51,035	[7]
Policy acquisition costs										64,442	41,408	3,169	[7]
General and administrative expenses										43,280	38,715	11,121	[7]
Share compensation expenses										2,543	2,083	135	[7]
Total segmental deductions										294,077	254,084	65,460	[7]
Segmental income										(19,933)	5,610	7,800	[7]
Validus share of segmental income										$ (19,933)	$ 5,610	$ 7,800
Selected ratios:
Ratio of net to gross premiums written										93.00%	93.20%	90.10%	[7]
Losses and loss expenses ratio										67.30%	66.40%	69.90%	[7]
Policy acquisition costs ratio										23.50%	16.00%	4.40%	[7]
General and administrative expenses ratio	[3]									16.80%	15.80%	15.40%	[7]
Expense ratio										40.30%	31.80%	19.80%	[7]
Combined ratio										107.60%	98.20%	89.70%	[7]
Operating Segments | Corporate and Investment
Underwriting deductions
General and administrative expenses										$ 72,249	$ 75,724	$ 80,210
Share compensation expenses										16,003	12,955	11,352
Total segmental deductions										88,252	88,679	91,562
Segmental income										(88,252)	(88,679)	(91,562)
Other items	[1]									(649)	(102,649)	(53,866)
Dividends on preferred shares										(4,455)	0	0
Net investment income	[8]									141,718	121,166	95,800
(Income) attributable to AlphaCat investors										0
Net (income) attributable to noncontrolling interests										0		0
Finance expenses	[8]									57,183	61,071	60,309
Tax benefit (expense)	[8]									19,819	(6,376)	(155)
Total expenses										130,071	156,126	152,026
Validus share of segmental income										48,362	(70,162)	(57,724)
Net realized gains on investments	[8]									14,680	1,698	12,160
Change in net unrealized gains (losses) on managed investments (a)	[8]									14,106	(32,007)	(1,030)
(Loss) income from investment affiliates										(2,083)	4,281	8,411
Foreign exchange gains	[8]									10,778	(8,172)	(10,700)
Other income (loss)										(766)	(1,002)	(2,243)
Transaction expenses	[9]									0	0	(8,096)	[2]
Total other items										36,715	(35,202)	(1,498)
Eliminations
Underwriting income
Gross premiums written										(26,673)	(42,718)	(53,457)
Reinsurance premiums ceded										26,673	42,718	53,457
Net premiums written										0	0	0
Change in unearned premiums										0	0	0
Net premiums earned										0	0	0
Other insurance related income (loss)										(20,737)	(24,881)	(26,796)
Segmental revenues										(20,737)	(24,881)	(26,796)
Underwriting deductions
Losses and loss expenses										0	0	0
Policy acquisition costs										(32)	(1,599)	(4,118)
General and administrative expenses										(20,817)	(23,519)	(23,834)
Share compensation expenses										0	0	0
Total segmental deductions										(20,849)	(25,118)	(27,952)
Segmental income										112	237	1,156
Net investment income										(597)
Validus share of segmental income										$ (485)	$ 237	$ 1,156
[1]	Other items includes finance expenses, tax (benefit) expense, foreign exchange gains (losses), net realized and change in net unrealized gains (losses) on investments, income from investment and operating affiliates and other income (loss).
[2]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.
[3]	The general and administrative expense ratio includes share compensation expenses.
[4]	The results of AlphaCat are presented on an asset manager basis, which is non-GAAP. A reconciliation of Validus’ share of AlphaCat segment income to segmental income is presented in the tables below.
[5]	The investment income from the AlphaCat funds and sidecars is based on equity accounting.
[6]	AlphaCat Direct includes direct investments from third party investors in AlphaCat Re.
[7]	The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.
[8]	These items exclude the components which are included in Validus’ share of AlphaCat and amounts which are consolidated from VIEs.
[9]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.

Segment information (Gross writ

Segment information (Gross written premiums by line of business) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue from External Customer [Line Items]
Gross premiums written	$ 339,454	$ 372,418	$ 764,042	$ 1,172,791	$ 309,605	$ 402,509	$ 726,168	$ 1,119,224	$ 2,648,705	$ 2,557,506	$ 2,358,865
Property
Revenue from External Customer [Line Items]
Gross premiums written									1,128,523	1,077,700	1,050,109	[1]
Marine
Revenue from External Customer [Line Items]
Gross premiums written									363,656	471,857	576,478	[1]
Specialty
Revenue from External Customer [Line Items]
Gross premiums written									927,746	782,463	677,026	[1]
Liability
Revenue from External Customer [Line Items]
Gross premiums written									$ 228,780	$ 225,486	$ 55,252	[1]
[1]	The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.

Segment information (Segment ge

Segment information (Segment geographic) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written		$ 339,454	$ 372,418	$ 764,042	$ 1,172,791	$ 309,605	$ 402,509	$ 726,168	$ 1,119,224	$ 2,648,705		$ 2,557,506	$ 2,358,865
Percent of gross premiums written										100.00%		100.00%	100.00%
United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 937,587		$ 954,311	$ 633,220
Percent of gross premiums written										35.40%		37.40%	26.80%
Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 221,766	[1]	$ 187,321	$ 221,092	[1]
Percent of gross premiums written	[1]									8.40%		7.30%	9.40%
Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 23,049		$ 21,544	$ 31,012
Percent of gross premiums written										0.90%		0.80%	1.30%
Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 65,781		$ 88,266	$ 103,851
Percent of gross premiums written										2.40%		3.50%	4.40%
Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 140,395		$ 134,133	$ 146,376
Percent of gross premiums written										5.30%		5.20%	6.20%
Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 49,867		$ 45,618	$ 47,426
Percent of gross premiums written										1.90%		1.80%	2.00%
Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 10,243		$ 10,022	$ 13,864
Percent of gross premiums written										0.40%		0.40%	0.60%
Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[2]									$ 127,252		$ 121,075	$ 114,479
Percent of gross premiums written	[2]									4.80%		4.70%	4.90%
Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 638,353		$ 607,979	$ 678,100
Percent of gross premiums written										24.10%		23.70%	28.80%
Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									$ 424,646		$ 338,345	$ 344,934
Percent of gross premiums written	[1]									16.00%		13.20%	14.60%
Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[3]									$ 648,119		$ 656,871	$ 702,611
Percent of gross premiums written	[3]									24.50%		25.70%	29.80%
Operating Segments | Validus Re
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										$ 1,111,054		$ 1,126,759	$ 1,118,532
Operating Segments | Validus Re | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										448,243		530,541	437,124
Operating Segments | Validus Re | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									51,902		52,860	76,370
Operating Segments | Validus Re | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										7,389		12,190	20,617
Operating Segments | Validus Re | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										28,967		48,240	57,223
Operating Segments | Validus Re | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										47,586		46,258	56,102
Operating Segments | Validus Re | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										40,099		38,885	42,813
Operating Segments | Validus Re | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										3,349		3,129	3,793
Operating Segments | Validus Re | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[2]									22,595		21,498	25,272
Operating Segments | Validus Re | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										201,887		223,060	282,190
Operating Segments | Validus Re | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									167,065		139,419	175,098
Operating Segments | Validus Re | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[3]									293,859		233,739	224,120
Operating Segments | AlphaCat
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[4]									270,402		176,126	126,785
Operating Segments | AlphaCat | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										64,766		41,134	26,067
Operating Segments | AlphaCat | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									22,206		8,107	6,727
Operating Segments | AlphaCat | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										4,949		624	1,019
Operating Segments | AlphaCat | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										3,245		2,504	2,305
Operating Segments | AlphaCat | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										0		38	0
Operating Segments | AlphaCat | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										3,221		1,671	608
Operating Segments | AlphaCat | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										207		458	214
Operating Segments | AlphaCat | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[2]									0		0	0
Operating Segments | AlphaCat | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										33,828		13,402	10,873
Operating Segments | AlphaCat | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									170,253		116,523	89,845
Operating Segments | AlphaCat | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[3]									1,555		5,067	0
Operating Segments | Talbot
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										970,702		1,018,835	1,101,770
Operating Segments | Talbot | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										103,415		106,679	108,458
Operating Segments | Talbot | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									148,347		127,540	139,570
Operating Segments | Talbot | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										10,844		8,974	9,736
Operating Segments | Talbot | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										34,264		38,657	45,615
Operating Segments | Talbot | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										102,293		103,318	116,281
Operating Segments | Talbot | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										6,580		5,171	4,116
Operating Segments | Talbot | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										6,834		6,666	10,194
Operating Segments | Talbot | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[2]									107,106		103,237	93,012
Operating Segments | Talbot | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										416,268		393,563	418,524
Operating Segments | Talbot | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									98,311		100,523	96,187
Operating Segments | Talbot | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[3]									352,708		418,070	478,601
Operating Segments | Western World Insurance Group, Inc
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										323,220		278,504	65,235	[5]
Operating Segments | Western World Insurance Group, Inc | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										323,220		278,504	65,235
Operating Segments | Western World Insurance Group, Inc | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									0		0	0
Operating Segments | Western World Insurance Group, Inc | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										0		0	0
Operating Segments | Western World Insurance Group, Inc | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										0		0	0
Operating Segments | Western World Insurance Group, Inc | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										0		0	0
Operating Segments | Western World Insurance Group, Inc | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										0		0	0
Operating Segments | Western World Insurance Group, Inc | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										0		0	0
Operating Segments | Western World Insurance Group, Inc | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[2]									0		0	0
Operating Segments | Western World Insurance Group, Inc | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										0		0	0
Operating Segments | Western World Insurance Group, Inc | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									0		0	0
Operating Segments | Western World Insurance Group, Inc | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[3]									0		0	0
Eliminations
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(26,673)		(42,718)	(53,457)
Eliminations | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(2,057)		(2,547)	(3,664)
Eliminations | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									(689)		(1,186)	(1,575)
Eliminations | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(133)		(244)	(360)
Eliminations | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(695)		(1,135)	(1,292)
Eliminations | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(9,484)		(15,481)	(26,007)
Eliminations | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(33)		(109)	(111)
Eliminations | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(147)		(231)	(337)
Eliminations | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[2]									(2,449)		(3,660)	(3,805)
Eliminations | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written										(13,630)		(22,046)	(33,487)
Eliminations | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[1]									(10,983)		(18,120)	(16,196)
Eliminations | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	[3]									$ (3)		$ (5)	$ (110)
[1]	Represents risks in two or more geographic zones.
[2]	Represents risks in one geographic zone.
[3]	The other locations non-specific category refers to business for which an analysis of exposure by geographic zone is not applicable since these exposures can span multiple geographic areas and, in some instances, are not fixed locations.
[4]	The results of AlphaCat are presented on an asset manager basis, which is non-GAAP. A reconciliation of Validus’ share of AlphaCat segment income to segmental income is presented in the tables below.
[5]	The results of Western World have been included in the Company’s consolidated results from the October 2, 2014 date of acquisition.

Statutory and regulatory req137

Statutory and regulatory requirements (Statutory capital and surplus and statutory net income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Bermuda
Statutory Accounting Practices [Line Items]
Required statutory capital and surplus	$ 734,045	$ 1,463,408
Actual statutory capital and surplus	3,712,369	3,469,849
Statutory net income (loss)	369,684	329,260	$ 511,652
United States
Statutory Accounting Practices [Line Items]
Required statutory capital and surplus	78,342	80,047
Actual statutory capital and surplus	416,746	421,047
Statutory net income (loss)	7,795	32,255	105,210
Switzerland
Statutory Accounting Practices [Line Items]
Required statutory capital and surplus	267,000	259,000
Actual statutory capital and surplus	806,099	750,356
Statutory net income (loss)	$ 46,362	$ 21,379	$ 44,939

Statutory and regulatory req138

Statutory and regulatory requirements (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)subsidiariesdirector	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Statutory Accounting Practices [Line Items]
Actual dividends received from subsidiaries	$ 320,000	$ 465,000
Bermuda
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	3,712,369	3,469,849
Statutory net income (loss)	369,684	329,260	$ 511,652
Unrestricted net assets available for dividend payments or return of capital	$ 1,335,300	1,008,367
Number of wholly owned subsidiaries | subsidiaries	5
Percentage Of Total Statutory Capital And Surplus Limit	25.00%
Payment Of Dividends Notification Period Required	7 days
Number Of Directors Required For Affidavit | director	2
Percentage Of Total Statutory Capital Limit	15.00%
United Kingdom
Statutory Accounting Practices [Line Items]
Actual dividends received from subsidiaries	$ 30,000	65,000
United States
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	416,746	421,047
Statutory net income (loss)	$ 7,795	32,255	105,210
Number of wholly owned subsidiaries | subsidiaries	3
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval	$ 490	17,599
Statutory Accounting Practices, Dividends Paid with Approval of Regulatory Agency	$ 18,500	80,300
Maximum Permitted Dividends Percentage Statutory Capital	10.00%
Switzerland
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	$ 806,099	750,356
Statutory net income (loss)	$ 46,362	$ 21,379	$ 44,939
Maximum Permitted Dividends Percentage Annual Profit	20.00%
Maximum Permitted Dividends Percentage Statutory Capital	50.00%
Special Purpose Insurer | Bermuda
Statutory Accounting Practices [Line Items]
Number of wholly owned subsidiaries | subsidiaries	2

Subsequent events (Details)

Subsequent events (Details) - USD ($) $ / shares in Units, $ in Thousands	Feb. 09, 2017	Jan. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Subsequent Event [Line Items]
Cash dividends declared per share			$ 0.35	$ 0.35	$ 0.35	$ 0.35	$ 0.32	$ 0.32	$ 0.32	$ 0.32	$ 1.40	$ 1.28	$ 1.20
Common shares
Subsequent Event [Line Items]
Cash dividends declared per share			0.35	0.35	$ 0.35	$ 0.35	$ 0.32	$ 0.32	$ 0.32	$ 0.32
Series A Preferred Stock
Subsequent Event [Line Items]
Cash dividends declared per share			$ 0.3671875	$ 0.3753472
Subsequent event | ADM Crop Risk Services
Subsequent Event [Line Items]
Payments to Acquire Businesses, Gross		$ 127,500
Subsequent event | Common shares
Subsequent Event [Line Items]
Cash dividends declared per share	$ 0.38
Subsequent event | Series A Preferred Stock
Subsequent Event [Line Items]
Cash dividends declared per share	$ 0.3671875

Condensed unaudited quarterl140

Condensed unaudited quarterly financial information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues
Gross premiums written	$ 339,454	$ 372,418	$ 764,042	$ 1,172,791	$ 309,605	$ 402,509	$ 726,168	$ 1,119,224	$ 2,648,705	$ 2,557,506	$ 2,358,865
Reinsurance premiums ceded	(40,635)	(45,006)	(36,229)	(167,835)	(33,128)	(48,810)	(55,418)	(191,325)	(289,705)	(328,681)	(313,208)
Net premiums written	298,819	327,412	727,813	1,004,956	276,477	353,699	670,750	927,899	2,359,000	2,228,825	2,045,657
Change in unearned premiums	241,580	236,363	(154,090)	(433,688)	266,823	201,312	(98,062)	(352,009)	(109,835)	18,064	(52,602)
Net premiums earned	540,399	563,775	573,723	571,268	543,300	555,011	572,688	575,890	2,249,165	2,246,889	1,993,055
Net investment income	38,153	43,514	39,257	29,461	31,612	31,572	33,611	31,029	150,385	127,824	100,086
Net realized gains on investments	9,220	4,397	2,724	(584)	(2,928)	(1,187)	2,244	4,169	15,757	2,298	14,917
Change in net unrealized gains (losses) on managed investments (a)	(67,460)	5,459	31,428	47,444	(34,862)	3,916	(34,676)	33,227	16,871	(32,395)	(2,842)
Income Loss From Equity Method Investment Investment Affiliates	2,166	453	(589)	(4,113)	(1,261)	2,482	284	2,776	(2,083)	4,281	8,411
Other insurance related income and other income	568	(610)	824	1,413	2,545	1,526	100	940	2,195	5,111	1,229
Foreign exchange gains (losses)	(901)	(766)	6,286	6,245	797	(2,592)	(2,671)	(4,265)	10,864	(8,731)	(12,181)
Revenues	522,145	616,222	653,653	651,134	539,203	590,728	571,580	643,766	2,443,154	2,345,277	2,102,675
Expenses
Losses and loss expenses	275,126	258,394	307,130	224,447	214,748	256,010	266,146	240,929	1,065,097	977,833	765,015
Policy acquisition costs	120,889	113,434	107,966	107,193	102,285	105,039	104,323	98,411	449,482	410,058	339,467
General and administrative expenses	77,955	82,443	89,688	86,208	98,563	96,886	84,025	84,235	336,294	363,709	329,362
Share compensation expenses	10,442	10,501	10,727	11,237	10,062	9,983	9,242	9,054	42,907	38,341	33,073
Finance expenses	14,630	14,521	14,166	15,203	16,581	18,512	18,682	20,967	58,520	74,742	68,324
Total expenses	499,042	479,293	529,677	444,288	442,239	486,430	482,418	453,596	1,952,300	1,864,683	1,543,337
Income before taxes, loss from operating affiliate and (income) attributable to AlphaCat investors	23,103	136,929	123,976	206,846	96,964	104,298	89,162	190,170	490,854	480,594	559,338
Tax benefit (expense)	21,147	(1,830)	(1,706)	2,118	756	(2,018)	(2,549)	(2,565)	19,729	(6,376)	(155)
(Loss) income from operating affiliates	0	0	0	(23)	(1,708)	(7,963)	1,738	3,984	(23)	(3,949)	(4,340)
(Income) attributable to AlphaCat investors	(7,080)	(5,564)	(6,114)	(4,600)	(974)	(1,438)	0	0	(23,358)	(2,412)	0
Net income (loss)	37,170	129,535	116,156	204,341	95,038	92,879	88,351	191,589	487,202	467,857	554,843
Net (income) attributable to noncontrolling interests	(27,200)	(37,439)	(21,193)	(37,531)	(25,996)	(26,229)	(22,561)	(18,178)	(123,363)	(92,964)	(74,880)
Net income available to Validus	9,970	92,096	94,963	166,810	69,042	66,650	65,790	173,411	363,839	374,893	479,963
Dividends on preferred shares	(2,203)	(2,252)	0	0	0	0	0	0	(4,455)	0	0
Net income available to Validus common shareholders	$ 7,767	$ 89,844	$ 94,963	$ 166,810	$ 69,042	$ 66,650	$ 65,790	$ 173,411	$ 359,384	$ 374,893	$ 479,963
Earnings per share
Basic earnings per share available to common shareholders	$ 0.10	$ 1.12	$ 1.16	$ 2.01	$ 0.84	$ 0.79	$ 0.77	$ 2.07	$ 4.43	$ 4.47	$ 5.24
Earnings per diluted share available to common shareholders	0.10	1.11	1.14	1.98	0.81	0.78	0.75	1.98	4.36	4.34	5.07
Selected ratios:
Cash dividends declared per share	$ 0.35	$ 0.35	$ 0.35	$ 0.35	$ 0.32	$ 0.32	$ 0.32	$ 0.32	$ 1.40	$ 1.28	$ 1.20

Schedule I - Summary of inve141

Schedule I - Summary of investments (Details) $ in Thousands	Dec. 31, 2016USD ($)
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	$ 8,761,087
Fair value	8,744,912
Amount at which shown on the Balance Sheet	8,744,912
Total fixed maturities
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	5,584,599
Fair value	5,543,030
Amount at which shown on the Balance Sheet	5,543,030
U.S. government and government agency
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	809,392
Fair value	804,126
Amount at which shown on the Balance Sheet	804,126
Non-U.S. government and government agency
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	245,651
Fair value	240,791
Amount at which shown on the Balance Sheet	240,791
U.S. states, municipalities and political subdivisions
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	271,742
Fair value	271,830
Amount at which shown on the Balance Sheet	271,830
Agency residential mortgage-backed securities
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	684,490
Fair value	679,595
Amount at which shown on the Balance Sheet	679,595
Non-agency residential mortgage-backed securities
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	15,858
Fair value	15,477
Amount at which shown on the Balance Sheet	15,477
U.S. corporate
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	1,540,036
Fair value	1,534,508
Amount at which shown on the Balance Sheet	1,534,508
Non-U.S. corporate
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	418,520
Fair value	410,227
Amount at which shown on the Balance Sheet	410,227
Bank loans
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	579,121
Fair value	570,399
Amount at which shown on the Balance Sheet	570,399
Catastrophe bonds
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	157,486
Fair value	158,331
Amount at which shown on the Balance Sheet	158,331
Asset-backed securities
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	528,563
Fair value	526,814
Amount at which shown on the Balance Sheet	526,814
Commercial mortgage backed securities
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	333,740
Fair value	330,932
Amount at which shown on the Balance Sheet	330,932
Total short-term investments
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	2,796,358
Fair value	2,796,170
Amount at which shown on the Balance Sheet	2,796,170
Total other investments
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amortized cost	380,130
Fair value	405,712
Amount at which shown on the Balance Sheet	$ 405,712

Schedule II - Condensed fina142

Schedule II - Condensed financial information of registrant (Balance Sheet) (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
ASSETS
Fixed maturities, at fair value	$ 5,543,030	$ 5,510,331
Cash and cash equivalents	419,976	723,109	$ 550,401	$ 729,333
Accrued investment income	26,488	23,897
Other assets	134,282	126,782
Total assets	11,349,755	10,515,812
LIABILITIES
Accounts payable and accrued expenses	587,648	627,331
Senior notes payable	245,362	245,161
Debentures and senior notes payable	782,588	782,829
Total liabilities	5,817,486	5,610,461
SHAREHOLDERS’ EQUITY
Common shares (Issued: 2016—161,279,976; 2015—160,570,772; Outstanding: 2016—79,132,252; 2015—82,900,617)	28,224	28,100
Treasury shares (2016—82,147,724; 2015—77,670,155)	(14,376)	(13,592)
Additional paid-in capital	821,023	1,002,980
Accumulated other comprehensive loss	(23,216)	(12,569)
Retained earnings	2,876,636	2,634,056
Total shareholders' equity	4,004,268	3,793,637	$ 3,878,860
Total liabilities and shareholders’ equity	$ 11,349,755	$ 10,515,812
Condensed Financial Information Balance Sheet Parenthetical Data [Abstract]
Preferred Stock, Shares Issued	6,000	0
Preferred Stock, Shares Outstanding	6,000	0
Authorized Share Capital	571,428,571	571,428,571
Common shares, par value	$ 0.175	$ 0.175
Common Stock, Shares, Issued	161,279,976	160,570,772	155,554,224	154,488,497
Common Stock, Shares, Outstanding	79,132,252	82,900,617	83,869,845
Treasury Stock, Shares	82,147,724	77,670,155
Parent Company
ASSETS
Fixed maturities, at fair value	$ 92,197	$ 28,403
Cash and cash equivalents	11,780	25,306	$ 29,798	$ 20,385
Investment in subsidiaries on an equity basis	4,383,800	4,198,809
Balances due from subsidiaries	0	10,389
Accrued investment income	239	49
Other assets	1,143	813
Total assets	4,489,159	4,263,769
LIABILITIES
Accounts payable and accrued expenses	26,884	29,633
Balances due to subsidiaries	28,622	0
Senior notes payable	245,362	245,161
Debentures and senior notes payable	350,000	350,000
Total liabilities	650,868	624,794
SHAREHOLDERS’ EQUITY
Preferred Stock, Value, Issued	150,000	0
Common shares (Issued: 2016—161,279,976; 2015—160,570,772; Outstanding: 2016—79,132,252; 2015—82,900,617)	28,224	28,100
Treasury shares (2016—82,147,724; 2015—77,670,155)	(14,376)	(13,592)
Additional paid-in capital	821,023	1,002,980
Accumulated other comprehensive loss	(23,216)	(12,569)
Retained earnings	2,876,636	2,634,056
Total shareholders' equity	3,838,291	3,638,975
Total liabilities and shareholders’ equity	$ 4,489,159	$ 4,263,769

Schedule II - Condensed fina143

Schedule II - Condensed financial information of registrant (Income Statement) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues
Net investment income	$ 38,153	$ 43,514	$ 39,257	$ 29,461	$ 31,612	$ 31,572	$ 33,611	$ 31,029	$ 150,385	$ 127,824	$ 100,086
Change in net unrealized gains (losses) on managed investments (a)	(67,460)	5,459	31,428	47,444	(34,862)	3,916	(34,676)	33,227	16,871	(32,395)	(2,842)
Foreign exchange gains	(901)	(766)	6,286	6,245	797	(2,592)	(2,671)	(4,265)	10,864	(8,731)	(12,181)
Total revenues	522,145	616,222	653,653	651,134	539,203	590,728	571,580	643,766	2,443,154	2,345,277	2,102,675
Expenses
General and administrative expenses	77,955	82,443	89,688	86,208	98,563	96,886	84,025	84,235	336,294	363,709	329,362
Share compensation expenses	10,442	10,501	10,727	11,237	10,062	9,983	9,242	9,054	42,907	38,341	33,073
Finance expenses	14,630	14,521	14,166	15,203	16,581	18,512	18,682	20,967	58,520	74,742	68,324
Net income available to Validus	9,970	92,096	94,963	166,810	69,042	66,650	65,790	173,411	363,839	374,893	479,963
Dividends on preferred shares	(2,203)	(2,252)	0	0	0	0	0	0	(4,455)	0	0
Net income available to Validus common shareholders	$ 7,767	$ 89,844	$ 94,963	$ 166,810	$ 69,042	$ 66,650	$ 65,790	$ 173,411	359,384	374,893	479,963
Change in foreign currency translation adjustments									(10,440)	(3,716)	(7,501)
Change in minimum pension liability, net of tax									(484)	544	(210)
Change in fair value of cash flow hedge									277	(841)	(228)
Other comprehensive loss									(10,647)	(4,013)	(7,939)
Comprehensive income (loss) available (attributable) to Validus									353,192	370,880	472,024
Parent Company
Revenues
Net investment income									1,195	317	14
Net realized gains on investments									8,020	0	0
Change in net unrealized gains (losses) on managed investments (a)									(276)	(395)	0
Foreign exchange gains									1,932	715	648
Total revenues									10,871	637	662
Expenses
General and administrative expenses									72,235	74,015	86,108
Share compensation expenses									6,832	7,261	6,424
Finance expenses									47,108	47,722	47,689
Total expenses									126,175	128,998	140,221
(Loss) before equity in net earnings of subsidiaries									(115,304)	(128,361)	(139,559)
Equity in net earnings of subsidiaries									479,143	503,254	619,522
Net income available to Validus									363,839	374,893	479,963
Dividends on preferred shares									(4,455)	0	0
Net income available to Validus common shareholders									359,384	374,893	479,963
Change in foreign currency translation adjustments									(10,440)	(3,716)	(7,501)
Change in minimum pension liability, net of tax									(484)	544	(210)
Change in fair value of cash flow hedge									277	(841)	(228)
Other comprehensive loss									(10,647)	(4,013)	(7,939)
Comprehensive income (loss) available (attributable) to Validus									$ 353,192	$ 370,880	$ 472,024

Schedule II - Condensed fina144

Schedule II - Condensed financial information of registrant (Cash flow) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows provided by (used in) operating activities
Net income available to Validus	$ 9,970	$ 92,096	$ 94,963	$ 166,810	$ 69,042	$ 66,650	$ 65,790	$ 173,411	$ 363,839	$ 374,893	$ 479,963
Adjustments to reconcile net income to net cash provided by operating activities:
Dividends received from subsidiaries									320,000	465,000
Amortization of discount on senior notes									108	108	108
Change in net unrealized losses on investments	67,460	$ (5,459)	$ (31,428)	(47,444)	34,862	$ (3,916)	$ 34,676	(33,227)	(16,871)	32,395	2,842
Amortization of premium on fixed maturity investments									17,961	23,075	19,107
Change in:
Net cash provided by operating activities									410,203	334,506	340,161
Cash flows (used in) investing activities
Purchases of fixed maturity investments									(3,074,703)	(4,225,031)	(4,391,814)
Net cash used in investing activities									(991,793)	(370,834)	(162,681)
Cash flows provided by (used in) financing activities
Net proceeds on issuance of preferred shares									144,852	0	0
(Redemption) issuance of common shares, net									(7,701)	17,407	5,347
Purchases of common shares under repurchase program									(212,675)	(260,430)	(510,952)
Dividends paid on preferred shares									(4,455)	0	0
Dividends paid on common shares									(115,625)	(112,967)	(117,043)
Net cash provided by (used in) financing activities									301,089	226,641	(331,102)
Net increase in cash									(303,133)	172,708	(178,932)
Cash and cash equivalents - beginning of year				723,109				550,401	723,109	550,401	729,333
Cash and cash equivalents - end of year	419,976				723,109				419,976	723,109	550,401
Parent Company
Cash flows provided by (used in) operating activities
Net income available to Validus									363,839	374,893	479,963
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in net earnings of subsidiary									(479,143)	(503,254)	(619,522)
Dividends received from subsidiaries									30,000	620,700	100,000
Net realized gains on investments									(8,020)	0	0
Amortization of discount on senior notes									108	108	108
Share compensation expenses									6,832	7,261	6,424
Change in net unrealized losses on investments									276	395	0
Amortization of premium on fixed maturity investments									115	105	0
Change in:
Other assets									(238)	173	528
Accrued investment income									(190)	(49)	0
Balances due from subsidiaries									10,389	30,689	(12,030)
Balances due to subsidiaries									28,622	0	0
Accounts payable and accrued expenses									(4,348)	5,080	2,624
Net cash provided by operating activities									(51,758)	536,101	(41,905)
Cash flows (used in) investing activities
Purchases of fixed maturity investments									(56,164)	(28,903)	0
Investment in subsidiaries									0	(555,700)	0
Return of capital from subsidiaries									290,000	400,000	673,966
Net cash used in investing activities									233,836	(184,603)	673,966
Cash flows provided by (used in) financing activities
Net proceeds on issuance of preferred shares									144,852	0	0
(Redemption) issuance of common shares, net									(7,701)	17,407	5,347
Purchases of common shares under repurchase program									(212,675)	(260,430)	(510,952)
Dividends paid on preferred shares									(4,455)	0	0
Dividends paid on common shares									(115,625)	(112,967)	(117,043)
Net cash provided by (used in) financing activities									(195,604)	(355,990)	(622,648)
Net increase in cash									(13,526)	(4,492)	9,413
Cash and cash equivalents - beginning of year				$ 25,306				$ 29,798	25,306	29,798	20,385
Cash and cash equivalents - end of year	$ 11,780				$ 25,306				$ 11,780	$ 25,306	$ 29,798

Schedule III - Supplementary145

Schedule III - Supplementary insurance information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplementary Insurance Information, by Segment [Line Items]
Deferred acquisition costs	$ 209,227	$ 181,002	$ 161,022
Reserve for losses and loss expenses	2,995,195	2,996,567	3,243,147
Unearned premiums	1,076,049	966,210	989,229
Net premiums earned	2,249,165	2,246,889	1,993,055
Net investment income	150,385	127,824	100,086
Losses and loss expenses	1,065,097	977,833	765,015
Amortization of deferred acquisition costs	449,482	410,058	339,467
Other operating expenses	379,201	402,050	362,435
Net premiums written	2,359,000	2,228,825	2,045,657
Validus Re
Supplementary Insurance Information, by Segment [Line Items]
Deferred acquisition costs	79,588	60,459	59,091
Reserve for losses and loss expenses	1,116,753	1,146,869	1,333,878
Unearned premiums	352,646	294,509	305,138
Net premiums earned	943,945	990,213	917,284
Net investment income	0	0	0
Losses and loss expenses	411,488	457,976	307,290
Amortization of deferred acquisition costs	181,040	166,387	141,670
Other operating expenses	83,804	88,778	84,478
Net premiums written	999,490	977,671	954,854
Talbot
Supplementary Insurance Information, by Segment [Line Items]
Deferred acquisition costs	95,237	92,095	95,246
Reserve for losses and loss expenses	1,301,517	1,302,635	1,352,056
Unearned premiums	551,815	533,558	552,660
Net premiums earned	781,916	838,091	879,774
Net investment income	0	0	0
Losses and loss expenses	424,946	347,322	423,394
Amortization of deferred acquisition costs	177,127	187,535	187,162
Other operating expenses	147,557	167,679	162,174
Net premiums written	794,973	819,939	909,559
Western World Insurance Group, Inc
Supplementary Insurance Information, by Segment [Line Items]
Deferred acquisition costs	34,841	28,622	9,566
Reserve for losses and loss expenses	589,500	600,331	613,551
Unearned premiums	158,945	130,101	133,185
Net premiums earned	273,232	258,650	72,996
Net investment income	0	0	0
Losses and loss expenses	183,812	171,878	51,035
Amortization of deferred acquisition costs	64,442	41,408	3,169
Other operating expenses	45,823	40,798	11,256
Net premiums written	300,586	259,627	58,807
AlphaCat
Supplementary Insurance Information, by Segment [Line Items]
Deferred acquisition costs	4,060	2,526	1,281
Reserve for losses and loss expenses	48,534	11,013	15,278
Unearned premiums	38,961	24,643	13,060
Net premiums earned	250,072	159,935	123,001
Net investment income	0	0	0
Losses and loss expenses	44,851	657	(16,704)
Amortization of deferred acquisition costs	26,905	16,327	11,584
Other operating expenses	34,582	39,635	36,799
Net premiums written	263,951	171,588	122,437
Corporate & Eliminations
Supplementary Insurance Information, by Segment [Line Items]
Deferred acquisition costs	(4,499)	(2,700)	(4,162)
Reserve for losses and loss expenses	(61,109)	(64,281)	(71,616)
Unearned premiums	(26,318)	(16,601)	(14,814)
Net premiums earned	0	0	0
Net investment income	150,385	127,824	100,086
Losses and loss expenses	0	0	0
Amortization of deferred acquisition costs	(32)	(1,599)	(4,118)
Other operating expenses	67,435	65,160	67,728
Net premiums written	$ 0	$ 0	$ 0

Schedule IV - Reinsurance (Deta

Schedule IV - Reinsurance (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Schedule of Reinsurance Premiums for Insurance Companies [Abstract]
Direct gross									$ 853,885	$ 838,755	$ 683,028
Ceded to other companies	$ 40,635	$ 45,006	$ 36,229	$ 167,835	$ 33,128	$ 48,810	$ 55,418	$ 191,325	289,705	328,681	313,208
Assumed from other companies									1,794,820	1,718,751	1,675,837
Net amount	$ 298,819	$ 327,412	$ 727,813	$ 1,004,956	$ 276,477	$ 353,699	$ 670,750	$ 927,899	$ 2,359,000	$ 2,228,825	$ 2,045,657
Percentage of amount assumed to net									76.00%	77.00%	82.00%

Schedule VI - Supplemental i147

Schedule VI - Supplemental information for property-casualty underwriters (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Losses and loss expenses incurred related to current year	$ 1,281,289	$ 1,283,970	$ 1,024,256
Losses and loss expenses incurred related to prior year	(216,192)	(306,137)	(259,241)
Property and casualty insurance company subsidiaries
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Deferred acquisition costs	209,227	181,002	161,022
Reserves for losses and loss expenses	2,995,195	2,996,567	3,243,147
Reserves for unearned premiums	1,076,049	966,210	989,229
Net earned premiums	2,249,165	2,246,889	1,993,055
Net investment income	150,385	127,824	100,086
Losses and loss expenses incurred related to current year	1,281,289	1,283,970	1,024,256
Losses and loss expenses incurred related to prior year	(216,192)	(306,137)	(259,241)
Net paid losses and loss expenses	1,114,402	1,167,839	1,063,653
Amortization of deferred acquisition costs	449,482	410,058	339,467
Net premiums written	$ 2,359,000	$ 2,228,825	$ 2,045,657