Endurance Specialty (ENH) 10-Q 6 Nov 15 2015 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Nov. 02, 2015
Document and Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Entity Registrant Name	Endurance Specialty Holdings Ltd.
Entity Central Index Key	1,179,755
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		66,621,848

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
ASSETS
Fixed maturity investments, trading at fair value (amortized cost: $1,376,743 and nil at September 30, 2015 and December 31, 2014, respectively)	$ 1,372,030	$ 0
Fixed maturity investments, available for sale at fair value (amortized cost: $4,615,296 and $5,032,506 at September 30, 2015 and December 31, 2014, respectively)	4,656,145	5,092,581
Short-term investments, trading at fair value (amortized cost: $348,581 and nil at September 30, 2015 and December 31, 2014, respectively)	348,582	0
Short-term investments, available for sale at fair value (amortized cost: $16,356 and $9,015 at September 30, 2015 and December 31, 2014, respectively)	16,356	9,014
Equity securities, trading at fair value (cost: $2,207 and nil at September 30, 2015 and December 31, 2014, respectively)	2,150	0
Equity securities, available for sale at fair value (cost: $535,764 and $303,922 at September 30, 2015 and December 31, 2014, respectively)	496,035	331,368
Other investments under equity method	842,446	541,454
Total investments	7,733,744	5,974,417
Cash and cash equivalents	1,242,997	745,472
Premiums receivable, net	2,068,484	883,450
Insurance and reinsurance balances receivable	115,047	122,214
Deferred acquisition costs	282,975	207,368
Prepaid reinsurance premiums	650,967	354,940
Reinsurance recoverable on unpaid losses	830,116	670,795
Reinsurance recoverable on paid losses	163,137	218,291
Accrued investment income	31,057	27,183
Goodwill and intangible assets	573,956	153,405
Deferred tax asset	54,463	48,995
Net receivable on sales of investments	85,911	38,877
Other assets	195,981	199,375
Total assets	14,028,835	9,644,782
LIABILITIES
Reserve for losses and loss expenses	4,489,836	3,846,859
Reserve for unearned premiums	2,230,552	1,254,519
Deposit liabilities	13,489	15,136
Reinsurance balances payable	794,935	375,711
Debt	915,147	527,715
Net payable on purchases of investments	157,671	151,682
Deferred tax liability	18,346	0
Other liabilities	352,515	287,978
Total liabilities	$ 8,972,491	$ 6,459,600
Commitments and contingent liabilities
SHAREHOLDERS' EQUITY
Preferred shares, Series A and B, total liquidation preference $430,000 (2014 - $430,000)	$ 17,200	$ 17,200
Common shares, Ordinary - 66,606,820 issued and outstanding (2014 - 44,765,153)	66,607	44,765
Additional paid-in capital	2,108,447	598,226
Accumulated other comprehensive (loss) income	(8,544)	76,706
Retained earnings	2,613,160	2,448,285
Total shareholders' equity available to Endurance Holdings	4,796,870	3,185,182
Non-controlling interests	259,474	0
Total shareholders' equity	5,056,344	3,185,182
Total liabilities and shareholders' equity	$ 14,028,835	$ 9,644,782

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Investments [Abstract]
Fixed maturity investments, trading, amortized cost	$ 1,376,743	$ 0
Fixed maturity investments, available for sale, amortized cost	4,615,296	5,032,506
Short-term investments, trading, amortized cost	348,581	0
Short-term investments, available for sale, amortized cost	16,356	9,015
Equity securities, trading, cost	2,207	0
Equity securities, available for sale, cost	535,764	303,922
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock, aggregate liquidation preference	$ 430,000	$ 430,000
Common stock, shares issued	66,606,820	44,765,153
Common stock, shares outstanding	66,606,820	44,765,153

Condensed Consolidated Statemen

Condensed Consolidated Statements Of Income And Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues
Gross premiums written	$ 642,597	$ 626,110	$ 2,805,213	$ 2,473,050
Ceded premiums written	(305,907)	(236,004)	(1,144,486)	(772,812)
Net premiums written	336,690	390,106	1,660,727	1,700,238
Change in unearned premiums	220,313	124,789	(255,730)	(307,539)
Net premiums earned	557,003	514,895	1,404,997	1,392,699
Net investment income	16,533	25,357	90,646	105,649
Net realized and unrealized gains	5,029	9,788	32,898	18,071
Net impairment losses recognized in earnings	(38)	(102)	(1,111)	(411)
Other underwriting income (loss)	227	2,123	4,022	(3,939)
Total revenues	578,754	552,061	1,531,452	1,512,069
Expenses
Net losses and loss expenses	263,993	290,269	675,051	726,361
Acquisition expenses	90,457	93,392	257,521	244,150
General and administrative expenses	60,793	68,946	170,648	186,759
Corporate expenses	74,308	11,969	99,210	53,817
Amortization of intangibles	11,318	1,623	14,496	4,863
Net foreign exchange losses	8,621	783	29,154	4,066
Interest expense	12,324	13,127	30,445	31,910
Total expenses	521,814	480,109	1,276,525	1,251,926
Income before income taxes	56,940	71,952	254,927	260,143
Income tax (expense) benefit	(2,410)	4,282	(7,712)	3,734
Net income	54,530	76,234	247,215	263,877
Net income attributable to non-controlling interests	(2,707)	0	(2,707)	0
Net income available to Endurance Holdings	51,823	76,234	244,508	263,877
Preferred dividends	(8,188)	(8,188)	(24,564)	(24,564)
Net income available to Endurance Holdings' common and participating common shareholders	43,635	68,046	219,944	239,313
Comprehensive income
Net income	54,530	76,234	247,215	263,877
Other comprehensive (loss) income
Net unrealized holding (losses) gains on investments arising during the period (net of other-than-temporary impairment losses recognized in other comprehensive (loss) income, reclassification adjustment and applicable deferred income taxes of $1,323 and ($3,358) for the nine months ended September 30, 2015 and 2014, respectively)	(29,906)	(34,357)	(72,396)	26,682
Foreign currency translation adjustments	(15,625)	(20,404)	(12,920)	(8,181)
Reclassification adjustment for net losses on derivative designated as cash flow hedge included in net income	22	22	66	67
Other comprehensive (loss) income	(45,509)	(54,739)	(85,250)	18,568
Comprehensive income	9,021	21,495	161,965	282,445
Comprehensive income attributable to non-controlling interests	(2,707)	0	(2,707)	0
Comprehensive income attributable to Endurance Holdings common and participating common shareholders	$ 6,314	$ 21,495	$ 159,258	$ 282,445
Per share data attributable to Endurance Holdings common shareholders
Basic earnings per Endurance Holdings common share	$ 0.73	$ 1.52	$ 4.41	$ 5.36
Diluted earnings per Endurance Holdings common share	0.73	1.52	4.39	5.36
Dividend per Endurance Holdings common share	$ 0.35	$ 0.34	$ 1.05	$ 1.02

Condensed Consolidated Stateme5

Condensed Consolidated Statements Of Income And Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Other comprehensive (loss) income, net unrealized holding (losses) gains on investments arising during the period, tax	$ 1,323	$ (3,358)

Condensed Consolidated Stateme6

Condensed Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Cumulative Foreign Currency Translation Adjustments [Member]	Unrealized Holding Gains On Investments, Net Of Deferred Taxes [Member]	Accumulated Derivative Loss On Cash Flow Hedging Instruments [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Noncontrolling Interest [Member]	Retained Earnings [Member]
Balance, beginning of period at Dec. 31, 2013		$ 17,200	$ 44,369	$ 569,116	$ 18,636	$ 45,950	$ (1,855)			$ 2,193,133
Issuance of common shares, net of forfeitures			382	1,270
Settlement of equity awards				(4,039)
Stock-based compensation expense				23,983
Foreign currency translation adjustments	$ (8,181)				(8,181)
Net unrealized holding (losses) gains arising during the period, net of other-than-temporary impairment losses and reclassification adjustment	26,682					26,682
Net change from current period hedging transactions, net of reclassification adjustment							67
Net income	263,877									263,877
Net income attributable to non-controlling interests	0								$ 0
Dividends on preferred shares	(24,564)									(24,564)
Dividends on common shares										(45,572)
Balance, end of period at Sep. 30, 2014	3,120,454	17,200	44,751	590,330	10,455	72,632	(1,788)	$ 81,299		2,386,874
Non-controlling interests									0
Total shareholders' equity	3,120,454
Non-controlling interests	0
Total shareholders' equity	3,185,182
Balance, beginning of period at Dec. 31, 2014	3,185,182	17,200	44,765	598,226	(7,628)	86,100	(1,766)			2,448,285
Issuance of common shares, net of forfeitures			21,842	1,474,432
Settlement of equity awards				(10,494)
Stock-based compensation expense				46,283
Foreign currency translation adjustments	(12,920)				(12,920)
Net unrealized holding (losses) gains arising during the period, net of other-than-temporary impairment losses and reclassification adjustment	(72,396)					(72,396)
Net change from current period hedging transactions, net of reclassification adjustment							66
Net income	247,215									247,215
Net income attributable to non-controlling interests	2,707								$ (2,707)
Dividends on preferred shares	(24,564)									(24,564)
Dividends on common shares										(55,069)
Balance, end of period at Sep. 30, 2015	4,796,870	$ 17,200	$ 66,607	$ 2,108,447	$ (20,548)	$ 13,704	$ (1,700)	$ (8,544)		$ 2,613,160
Non-controlling interests	259,474
Total shareholders' equity	$ 5,056,344

Condensed Consolidated Stateme7

Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash flows (used in) provided by operating activities
Net income	$ 247,215	$ 263,877
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Amortization of net premium on investments	34,116	34,128
Amortization of other intangibles and depreciation	29,291	20,593
Net realized and unrealized gains	(32,898)	(18,071)
Net impairment losses recognized in earnings	1,111	411
Deferred taxes	3,437	(5,058)
Stock-based compensation expense	46,283	23,983
Equity in undistributed earnings of other investments	1,758	(22,542)
Premiums receivable, net	(845,891)	(783,030)
Insurance and reinsurance balances receivable	21,085	4,290
Deferred acquisition costs	(75,607)	(60,410)
Prepaid reinsurance premiums	(227,337)	(226,804)
Reinsurance recoverable on unpaid losses	(119,269)	27,426
Reinsurance recoverable on paid losses	63,141	(1,372)
Accrued investment income	4,996	452
Other assets	(319)	(152)
Reserve for losses and loss expenses	(77,954)	(104,776)
Reserve for unearned premiums	477,440	533,317
Deposit liabilities	(1,647)	(1,937)
Reinsurance balances payable	338,279	301,032
Other liabilities	38,741	66,815
Net cash flows (used in) provided by operating activities	(74,029)	52,172
Cash flows used in investing activities
Proceeds from sales and maturities of trading investments	103,450	0
Proceeds from sales and maturities of available for sale investments	4,201,152	3,126,240
Proceeds from the redemption of other investments	124,801	34,072
Purchases of trading investments	(286,416)	0
Purchases of available for sale investments	(4,047,359)	(3,085,817)
Purchases of other investments	(116,988)	(52,731)
Net settlements of other assets	17,301	14,836
Purchases of fixed assets	(18,053)	(34,038)
Net cash received (paid) upon subsidiary acquisition	675,310	(45)
Net cash flows provided by investing activities	653,198	2,517
Cash flows used in financing activities
Issuance of common shares, net of forfeitures	24,378	1,480
Settlement of equity awards	(10,494)	(4,039)
Bridge facility costs paid	0	(4,750)
Proceeds from issuance of debt	791	591
Repayments and repurchases of debt	(794)	(499)
Dividends on preferred shares	(24,564)	(24,564)
Dividends on Endurance Holdings common shares	(54,959)	(45,548)
Net cash flows used in financing activities	(65,642)	(77,329)
Effect of exchange rate changes on cash and cash equivalents	(16,002)	(17,495)
Net increase (decrease) in cash and cash equivalents	497,525	(40,135)
Cash and cash equivalents, beginning of period	745,472	845,851
Cash and cash equivalents, end of period	$ 1,242,997	$ 805,716

General

General	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	1. General Endurance Specialty Holdings Ltd. ("Endurance Holdings" or the "Company") was organized as a Bermuda holding company on June 27, 2002. Endurance Holdings writes specialty lines of insurance and reinsurance on a global basis through its wholly-owned operating entities: Operating Subsidiaries Domicile Endurance Specialty Insurance Ltd. Bermuda Montpelier Reinsurance Ltd. Bermuda Blue Capital Management Ltd. Bermuda Endurance Worldwide Insurance Limited England Endurance at Lloyd's Limited England Endurance Reinsurance Corporation of America Delaware Endurance American Insurance Company Delaware Endurance American Specialty Insurance Company Delaware Endurance Risk Solutions Assurance Co. Delaware American Agri-Business Insurance Company Texas On July 31, 2015, the Company completed its acquisition of Montpelier Re Holdings Ltd. and its consolidated subsidiaries ("Montpelier"). Montpelier, through its operating subsidiaries, was a provider of global property and casualty reinsurance and insurance products. The Company's Unaudited Condensed Consolidated Statements of Income and Comprehensive Income for the three and nine months ended September 30, 2015 include the results of operations of Montpelier from August 1, 2015. See Note 11, Acquisition of Montpelier, for additional information with respect to the acquisition of Montpelier. As part of the acquisition of Montpelier, Endurance acquired Montpelier's Lloyd's operations. Syndicate 5151 ("Syndicate 5151") is the Company's Lloyd's syndicate. Endurance Corporate Capital Limited, a wholly-owned subsidiary of the Company, is Syndicate 5151's sole corporate member and Endurance at Lloyd's Limited, a wholly-owned subsidiary of the Company, is the managing agent for Syndicate 5151. Also as part of the acquisition of Montpelier, the Company acquired Blue Capital Management Ltd. ("BCML"), the manager of Montpelier's collateralized reinsurance and third party asset management operations, which operate under the name Blue Capital (Blue Capital is a registered trademark of the Company). Blue Capital was launched in 2012 as an asset management platform offering a range of catastrophe reinsurance-linked investment products to institutional and retail investors. Blue Capital Reinsurance Holdings Ltd. ("BCRH") is a Bermuda-based exempted limited liability holding company managed by BCML that provides fully-collateralized property catastrophe reinsurance and invests in various insurance-linked securities through its wholly-owned Bermuda-based subsidiaries, Blue Capital Re. Ltd. ("Blue Capital Re") and Blue Capital Re ILS Ltd. ("Blue Capital Re ILS"). BCRH's shares are listed on the New York Stock Exchange and the Bermuda Stock Exchange. Blue Capital Global Reinsurance Fund Limited (the "BCGR Listed Fund") is a closed-ended mutual fund incorporated in Bermuda and managed by BCML and serves as the feeder fund for the Blue Capital Global Reinsurance SA-I cell (the "BCGR Cell"). The BCGR Listed Fund's shares are listed on the Specialist Fund Market of the London Stock Exchange and on the Bermuda Stock Exchange. The Company is entitled to receive management and performance fees from BCRH and the BCGR Listed Fund for the services that it performs for these entities. See Note 3, Investments, for additional information with respect to the Blue Capital entities.

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	2. Summary of significant accounting policies The accompanying consolidated financial statements have been prepared on the basis of accounting principles generally accepted in the United States for interim financial information and with the instructions to the Quarterly Report on Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Results for the three and nine months ended September 30, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 . The consolidated financial statements include the accounts of Endurance Holdings and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Management is required to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying disclosures. Actual results could differ from those estimates. Among other matters, significant estimates and assumptions are used to record premiums written and ceded, to record the fair value of investments and to record reserves for losses and loss expenses and contingencies. Estimates and assumptions are periodically reviewed and the effects of revisions are recorded in the consolidated financial statements in the period that they are determined to be necessary. The balance sheet at December 31, 2014 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. These consolidated financial statements and notes thereto should be read in conjunction with the consolidated financial statements and notes thereto for the year ended December 31, 2014 contained in Endurance Holdings' Annual Report on Form 10-K for the fiscal year ended December 31, 2014 (the " 2014 Form 10-K"). Certain comparative information has been reclassified to conform to current year presentation. There were no material changes in the Company’s significant accounting and reporting policies subsequent to the filing of the 2014 Form 10-K with the exception of the additions to the Company's accounting policies described below relating to the Company's investments in trading securities and non-controlling interests in the current quarter. (a) Investments The Company classifies its fixed maturity investments, short-term investments and equity securities as trading or available for sale. Trading securities are carried at estimated fair value, with related net realized and unrealized gains or losses included in earnings. The Company has elected to account for trading securities using the fair value option under current accounting guidance, as the Company believes it represents the most meaningful measurement basis for these assets and liabilities. Available for sale securities are carried at estimated fair value, with related net unrealized gains or losses excluded from earnings and included in shareholders' equity as a component of accumulated other comprehensive (loss) income. Investment transactions are recorded on a trade date basis. The Company determines the fair value of its trading and available for sale investments in accordance with current accounting guidance, which defines fair value and establishes a fair value hierarchy based on inputs to the various valuation techniques used for each fair value measurement. The use of valuation techniques for any given investment requires a significant amount of judgment and consideration of factors specific to the underlying investment. Fair value measurements determined by the Company seek to maximize observable 2. Summary of significant accounting policies, cont'd. (a) Investments, cont'd. inputs and minimize the use of unobservable inputs. Current accounting guidance establishes three levels as follows: Level 1: Unadjusted quoted prices in active markets for identical assets or liabilities. Level 2: Quoted prices for similar assets in markets that are active, quoted prices for identical or similar assets in markets that are not active or inputs that are observable either directly or indirectly. Level 2 inputs include quoted prices for similar assets or liabilities other than quoted prices in Level 1; quoted prices in markets that are not active; or other inputs that are observable or can be derived principally from or corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3: Unobservable inputs that are supported by little or no market activity and are significant to the fair value of the assets or liabilities. Unobservable inputs reflect the Company’s own views about the assumptions that market participants would use in pricing the asset or liability. Level 3 assets and liabilities include financial instruments whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. The Company determines the estimated fair value of each individual security utilizing the highest level inputs available. Transfers between levels are assumed to occur at the end of each period. If the Company has the intent to sell a fixed maturity or short-term security classified as available for sale in an unrealized loss position or it is more likely than not that the Company will be required to sell the available for sale security, the Company deems the security to be other-than-temporarily impaired and writes down the carrying value of the security to fair value, thereby establishing a new cost basis. The amount of the write-down is recognized in earnings as an other-than-temporary impairment ("OTTI") loss. For fixed maturity and short-term investments classified as available for sale in an unrealized loss position for which a decision to sell has not been made and it is not more likely than not that the Company will be required to sell the security, the Company performs additional reviews to determine whether the investment will recover its amortized cost. If the amortized cost of the Company's fixed maturity and short-term investments classified as available for sale is, based on the judgment of management, unlikely to be recovered, the Company writes down the investment by the amount representing the credit related portion of the decline in value, thereby establishing a new cost basis. The amount of the write-down is recognized in earnings as an OTTI loss. The new cost basis is not changed for subsequent recoveries in fair value. To the extent the Company determines that the amortized cost of the Company’s fixed maturity and short-term investments classified as available for sale is likely to be recovered and the decline in value is related to non-credit factors (such as interest rates, market conditions, etc.) and not due to credit related factors, that remaining non-credit portion of the unrealized loss is recorded as a part of accumulated other comprehensive (loss) income in the shareholders' equity section of the Company's Unaudited Condensed Consolidated Balance Sheets. For equity securities classified as available for sale, the Company considers its ability and intent to hold the equity security in an unrealized loss position for a reasonable period of time to allow for a full recovery. When the Company determines that the decline in value of an equity security classified as available for sale is other-than-temporary, the Company reduces the cost of the equity security to its fair value and recognizes the loss in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income. The new cost basis is not changed for subsequent recoveries in fair value. 2. Summary of significant accounting policies, cont'd. (a) Investments, cont'd. Other investments within the Company's investment portfolio are comprised of (i) hedge funds, private investment funds and other investment funds that generally invest in senior secured bank debt, high yield credit securities, distressed debt, macro strategies, multi-strategy, equity long/short strategies, distressed real estate, and energy sector private equity ("alternative funds") and (ii) high yield loan funds ("specialty funds"). Other investments are accounted for using the equity method of accounting whereby the initial investment is recorded at cost. The carrying values of these investments are increased or decreased to reflect the Company's share of income or loss, which is included in net investment income, and are decreased for dividends. Due to the timing of the delivery of the final valuations reported by the managers of certain of our alternative and specialty funds, our investments in those funds are estimated based on the most recently available information including period end valuation statements, period end estimates, or, in some cases, prior month or quarter valuation statements. (b) Non-controlling interests The Company accounts for non-controlling interests in the shareholders' equity section of the Company's Unaudited Condensed Consolidated Balance Sheets in accordance with current accounting guidance regarding consolidation, and presents such non-controlling shareholders' interest in the net assets of the subsidiary. Net income attributable to non-controlling interest is presented separately in the Company's Unaudited Condensed Consolidated Statements of Income and Comprehensive Income. (c) Recent accounting pronouncements In February 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-02, "Amendments to the Consolidation Analysis". Under ASU 2015-02, all legal entities are required to evaluate whether they should consolidate certain legal entities. ASU 2015-02 set forth amendments: (1) modifying the evaluation of whether limited partnerships and similar legal entities are variable interest entities ("VIEs") or voting interest entities; (2) eliminating the presumption that a general partner should consolidate a limited partnership; (3) affecting the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships; and (4) providing a scope exception from consolidation guidance for certain reporting entities. ASU 2015-02 is effective for public business entities for annual and interim periods beginning after December 15, 2015. Early adoption is permitted. ASU 2015-02 may be applied retrospectively or by using a modified retrospective approach by recording a cumulative-effect adjustment to equity as of the beginning of the year of adoption. The Company is currently evaluating the impact of this guidance. In April 2015, the FASB issued ASU 2015-03, "Simplifying the Presentation of Debt Issuance Costs" ("ASU 2015-03"). The objective of ASU 2015-03 is to simplify the presentation of debt issuance costs by requiring direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in ASU 2015-03. ASU 2015-03 is effective for public business entities in annual and interim periods beginning after December 15, 2015. Early adoption is permitted. ASU 2015-03 should be applied retrospectively, and upon transition, applicable disclosures for a change in accounting principle shall be provided, including the transition method, a description of the prior period information that has been retroactively adjusted, and the effect of the change on the applicable financial statement line items. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements. In May 2015, the FASB issued ASU 2015-07, "Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)" ("ASU 2015-07"). The objective of ASU 2015-07 is to remove the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using net asset value per share. ASU 2015-07 is effective for public business entities in annual and interim periods beginning after December 15, 2015. Early adoption is permitted. ASU 2015-07 should be applied retrospectively. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements. 2. Summary of significant accounting policies, cont'd. (c) Recent accounting pronouncements, cont'd. In May 2015, the FASB issued ASU 2015-09, "Disclosures about Short-Duration Contracts" ("ASU 2015-09"). The objective of ASU 2015-09 is to make targeted improvements to disclosure requirements for insurance companies that issue short-duration contracts. The guidance requires additional disclosures of claims development tables, frequency of reported claims, and history of claims duration. This information is required to be disaggregated so that useful information is not obscured by either the inclusion of a large amount of insignificant detail, or the aggregation of items that have significantly different characteristics. ASU 2015-09 is effective for public business entities in annual periods beginning after December 15, 2015, and interim periods within annual periods beginning after December 15, 2016. Early adoption is permitted. ASU 2015-09 should be applied retrospectively. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements. In September 2015, the FASB issued ASU 2015-16, "Simplifying the Accounting for Measurement-Period Adjustments" ("ASU 2015-16"). ASU 2015-16 eliminates the requirement that an acquirer in a business combination account for measurement-period adjustments retrospectively. Instead, an acquirer will recognize a measurement-period adjustment during the period in which it determines the amount of the adjustment. ASU 2015-16 is effective for public business entities in annual periods beginning after December 15, 2015, and interim periods within annual periods beginning after December 15, 2015. Early adoption is permitted. The Company is currently evaluating the impact of this guidance.

Investments

Investments	9 Months Ended
	Sep. 30, 2015
Investments [Abstract]
Investments	3. Investments Net Investment Income The components of net investment income for the three and nine months ended September 30, 2015 and 2014 are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Fixed income investments $ 36,204 $ 28,944 $ 96,145 $ 88,616 Equity investments 1,748 1,015 5,200 3,289 Other investments (17,716 ) (1,785 ) (1,758 ) 22,542 Cash and cash equivalents 515 581 2,108 1,878 20,751 28,755 $ 101,695 $ 116,325 Investment expenses (4,218 ) (3,398 ) (11,049 ) (10,676 ) Net investment income $ 16,533 $ 25,357 $ 90,646 $ 105,649 Contractual maturities of the Company's fixed maturity and short-term investments are shown below as of September 30, 2015 and December 31, 2014 . Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. September 30, 2015 December 31, 2014 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 580,667 $ 581,281 $ 126,921 $ 127,821 Due after one year through five years 2,017,786 2,022,909 1,627,154 1,632,259 Due after five years through ten years 631,503 634,265 474,959 479,138 Due after ten years 61,583 63,470 43,314 46,720 Residential mortgage-backed securities 1,200,645 1,222,805 1,149,536 1,175,006 Commercial mortgage-backed securities 831,254 837,772 960,598 979,419 Collateralized loan and debt obligations 423,239 418,875 247,510 248,011 Asset-backed securities 610,299 611,736 411,529 413,221 Total $ 6,356,976 $ 6,393,113 $ 5,041,521 $ 5,101,595 3. Investments, cont'd. The following table summarizes the fair value of the fixed maturity investments, short-term investments and equity securities classified as trading at September 30, 2015 . The Company had no securities classified as trading as of December 31, 2014 . September 30, 2015 Fixed maturity investments U.S. government and agencies securities $ 208,610 U.S. state and municipal securities 4,625 Foreign government securities 48,562 Government guaranteed corporate securities 40,133 Corporate securities 559,228 Residential mortgage-backed securities 121,302 Commercial mortgage-backed securities 92,906 Collateralized loan and debt obligations (1) 102,976 Asset-backed securities 193,688 Total fixed maturity investments 1,372,030 Short-term investments 348,582 Total fixed income investments $ 1,720,612 Equity securities Equity investments $ 70 Preferred equity investments 2,080 Total equity securities $ 2,150 (1) Balances include amounts related to collateralized debt obligations held with total fair values of $44.1 million at September 30, 2015 . In addition to the Company's fixed maturity, short-term and equity investments, the Company invests in alternative funds and specialty funds. The Company's alternative funds and specialty funds are recorded on the Company's balance sheet as "other investments." At September 30, 2015 and December 31, 2014 , the Company had invested, net of capital returned, a total of $652.4 million and $387.2 million , respectively, in other investments. At September 30, 2015 and December 31, 2014 , the carrying value of other investments was $842.4 million and $541.5 million , respectively. The following table summarizes the composition and redemption restrictions of other investments as of September 30, 2015 and December 31, 2014 : September 30, 2015 Market Value Unfunded Commitments Ineligible for Redemption over next 12 months Alternative funds Hedge funds $ 641,089 $ — $ 89,387 Private investment funds 82,532 59,763 82,532 Other investment funds 23,577 — 25,011 Total alternative funds 747,198 59,763 196,930 Specialty funds High yield loan funds 95,248 — — Total specialty funds 95,248 — — Total other investments $ 842,446 $ 59,763 $ 196,930 3. Investments, cont'd. December 31, 2014 Market Value Unfunded Ineligible for Alternative funds Hedge funds $ 411,280 $ — $ 10,580 Private investment funds 74,664 70,542 74,664 Total alternative funds 485,944 70,542 85,244 Specialty funds High yield loan funds 55,510 — — Total specialty funds 55,510 — — Total other investments $ 541,454 $ 70,542 $ 85,244 Hedge funds – The redemption frequency of the hedge funds range from monthly to biennially with notice periods from 30 to 90 days. Over one year, it is estimated that the Company can liquidate approximately 86.1% of the hedge fund portfolio, with the remainder over the following two years. Private investment funds – The Company generally has no right to redeem its interest in any private investment funds in advance of dissolution of the applicable partnership. Instead, the nature of these investments is that distributions are received by the Company in connection with the liquidation of or distribution of earnings from the underlying assets of the applicable limited partnership. It is estimated that the majority of the underlying assets of the limited partnerships would liquidate over 5 to 10 years from inception of the limited partnership. A secondary market, with unpredictable liquidity, exists for limited partner interests in private equity funds. Other investment funds – Other investment funds includes funds on deposit with Lloyd's, which are restricted, and the Company's investment in BCGR Listed Fund, which represents the net liability of the Company's investment in BCGR Listed Fund that has not been deployed into the BCGR cell. High yield loan funds – There are generally no restrictions on the Company's right to redeem its interest in high yield loan funds with the exception of certain redemption frequency and notice requirements. The redemption frequency of these funds ranges from monthly to quarterly with notice periods from 30 to 90 days. Net Realized and Unrealized Gains Realized and unrealized gains and losses are recognized in earnings using the first in, first out method. The analysis of net realized and unrealized gains and the change in the fair value of investment-related derivative financial instruments for the three and nine months ended September 30, 2015 and 2014 is as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Gross realized gains on investment sales $ 20,107 $ 10,683 $ 57,420 $ 28,317 Gross realized losses on investment sales (8,236 ) (1,475 ) (18,190 ) (12,778 ) Net unrealized losses on trading securities (5,037 ) — (5,037 ) — Change in fair value of derivative financial instruments (1) (1,805 ) 580 (1,295 ) 2,532 Net realized and unrealized gains $ 5,029 $ 9,788 $ 32,898 $ 18,071 (1) For additional information on the Company's derivative financial instruments, see Note 7, Derivatives. 3. Investments, cont'd. Unrealized Gains and Losses The Company classifies some of its investments in fixed maturity investments, short-term investments and equities as available for sale. The amortized cost, fair value and related gross unrealized gains and losses on the Company’s securities classified as available for sale at September 30, 2015 and December 31, 2014 are as follows: September 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Fixed maturity investments U.S. government and agencies securities $ 590,216 $ 8,675 $ (1,358 ) $ 597,533 U.S. state and municipal securities 24,157 262 (108 ) 24,311 Foreign government securities 108,099 1,073 (522 ) 108,650 Government guaranteed corporate securities 25,416 392 (11 ) 25,797 Corporate securities 1,316,038 10,344 (6,844 ) 1,319,538 Residential mortgage-backed securities 1,080,411 23,611 (2,519 ) 1,101,503 Commercial mortgage-backed securities 737,543 10,676 (3,353 ) 744,866 Collateralized loan and debt obligations (1) 316,161 1,214 (1,476 ) 315,899 Asset-backed securities 417,255 1,792 (999 ) 418,048 Total fixed maturity investments 4,615,296 58,039 (17,190 ) 4,656,145 Short-term investments 16,356 — — 16,356 Total fixed income investments $ 4,631,652 $ 58,039 $ (17,190 ) $ 4,672,501 Equity securities Equity investments $ 407,206 $ 2,709 $ (40,460 ) $ 369,455 Emerging market debt funds 61,874 — (3,021 ) 58,853 Convertible funds 46,331 — (477 ) 45,854 Preferred equity investments 15,427 1,847 (326 ) 16,948 Short-term fixed income fund 4,926 — (1 ) 4,925 Total equity securities $ 535,764 $ 4,556 $ (44,285 ) $ 496,035 (1) Balances include amounts related to collateralized debt obligations held with total fair values of $13.2 million . 3. Investments, cont'd. December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Fixed maturity investments U.S. government and agencies securities $ 582,970 $ 6,471 $ (2,030 ) $ 587,411 U.S. state and municipal securities 39,340 191 (118 ) 39,413 Foreign government securities 239,217 2,983 (1,664 ) 240,536 Government guaranteed corporate securities 47,436 675 (9 ) 48,102 Corporate securities 1,354,370 12,742 (5,650 ) 1,361,462 Residential mortgage-backed securities 1,149,536 27,542 (2,072 ) 1,175,006 Commercial mortgage-backed securities 960,598 21,374 (2,553 ) 979,419 Collateralized loan and debt obligations (1) 247,510 1,449 (948 ) 248,011 Asset-backed securities 411,529 2,265 (573 ) 413,221 Total fixed maturity investments 5,032,506 75,692 (15,617 ) 5,092,581 Short-term investments 9,015 — (1 ) 9,014 Total fixed income investments $ 5,041,521 $ 75,692 $ (15,618 ) $ 5,101,595 Equity securities Equity investments $ 176,167 $ 29,660 $ (3,292 ) $ 202,535 Emerging market debt funds 60,826 — (676 ) 60,150 Convertible funds 46,331 — (220 ) 46,111 Preferred equity investments 13,858 2,022 (44 ) 15,836 Short-term fixed income funds 6,740 — (4 ) 6,736 Total equity securities $ 303,922 $ 31,682 $ (4,236 ) $ 331,368 (1) Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million . 3. Investments, cont'd. The following tables summarize, for all available for sale securities in an unrealized loss position at September 30, 2015 and December 31, 2014 , the aggregate fair value and gross unrealized loss by length of time the security has continuously been in an unrealized loss position. Less than 12 months 12 months or greater Total September 30, 2015 Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Fixed maturity investments U.S. government and agencies securities $ (438 ) $ 71,512 $ (920 ) $ 21,859 $ (1,358 ) $ 93,371 U.S. state and municipal securities (44 ) 2,311 (64 ) 708 (108 ) 3,019 Foreign government securities (442 ) 24,977 (80 ) 4,558 (522 ) 29,535 Government guaranteed corporate securities (11 ) 1,737 — — (11 ) 1,737 Corporate securities (5,687 ) 493,115 (1,157 ) 44,942 (6,844 ) 538,057 Residential mortgage-backed securities (1,300 ) 174,347 (1,219 ) 75,619 (2,519 ) 249,966 Commercial mortgage-backed securities (1,853 ) 214,560 (1,500 ) 45,802 (3,353 ) 260,362 Collateralized loan and debt obligations (1,075 ) 193,044 (401 ) 44,551 (1,476 ) 237,595 Asset-backed securities (807 ) 162,488 (192 ) 17,011 (999 ) 179,499 Total fixed income investments $ (11,657 ) $ 1,338,091 $ (5,533 ) $ 255,050 $ (17,190 ) $ 1,593,141 Equity securities Equity investments $ (40,460 ) $ 321,413 $ — $ — $ (40,460 ) $ 321,413 Emerging market debt funds (3,021 ) 58,853 — — (3,021 ) 58,853 Convertible funds (477 ) 45,854 — — (477 ) 45,854 Preferred equity investments (326 ) 9,027 — — (326 ) 9,027 Short-term fixed income fund (1 ) 4,924 — — (1 ) 4,924 Total equity securities $ (44,285 ) $ 440,071 $ — $ — $ (44,285 ) $ 440,071 (1) Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at September 30, 2015 . As of September 30, 2015 , 920 available for sale securities were in an unrealized loss position aggregating $61.5 million . Of those, 140 securities with aggregated unrealized losses of $5.5 million had been in a continuous unrealized loss position for twelve months or greater. 3. Investments, cont'd. Less than 12 months 12 months or greater Total December 31, 2014 Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Fixed maturity investments U.S. government and agencies securities $ (481 ) $ 155,350 $ (1,549 ) $ 45,993 $ (2,030 ) $ 201,343 U.S. state and municipal securities (47 ) 3,295 (71 ) 6,841 (118 ) 10,136 Foreign government securities (1,378 ) 37,904 (286 ) 4,306 (1,664 ) 42,210 Government guaranteed corporate securities (9 ) 4,598 — — (9 ) 4,598 Corporate securities (4,023 ) 533,139 (1,627 ) 84,278 (5,650 ) 617,417 Residential mortgage-backed securities (260 ) 62,832 (1,812 ) 108,899 (2,072 ) 171,731 Commercial mortgage-backed securities (1,068 ) 180,222 (1,485 ) 78,412 (2,553 ) 258,634 Collateralized loan and debt obligations (876 ) 176,439 (72 ) 6,491 (948 ) 182,930 Asset-backed securities (415 ) 199,205 (158 ) 19,095 (573 ) 218,300 Total fixed maturity investments (8,557 ) 1,352,984 (7,060 ) 354,315 (15,617 ) 1,707,299 Short-term investments (1 ) 1,953 — — (1 ) 1,953 Total fixed income investments $ (8,558 ) $ 1,354,937 $ (7,060 ) $ 354,315 $ (15,618 ) $ 1,709,252 Equity securities Equity investments $ (3,292 ) $ 53,591 $ — $ — $ (3,292 ) $ 53,591 Emerging market debt funds (676 ) 60,150 — — (676 ) 60,150 Convertible funds (220 ) 46,111 — — (220 ) 46,111 Preferred equity investments (44 ) 4,449 — — (44 ) 4,449 Short-term fixed income fund (4 ) 6,736 — — (4 ) 6,736 Total equity securities $ (4,236 ) $ 171,037 $ — $ — $ (4,236 ) $ 171,037 (1) Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at December 31, 2014 . As of December 31, 2014 , 747 available for sale securities were in an unrealized loss position aggregating $19.9 million . Of those, 171 securities with aggregated unrealized losses of $7.1 million had been in a continuous unrealized loss position for twelve months or greater. 3. Investments, cont'd. The increase in gross unrealized losses on the Company's fixed income investments at September 30, 2015 compared to December 31, 2014 was primarily due to widening of credit spreads and broad equity market declines during the nine months ended September 30, 2015 . At September 30, 2015 , the Company did not have the intent to sell any of the remaining fixed income investments in an unrealized loss position and determined that it was unlikely that the Company would be required to sell those securities in an unrealized loss position. The Company has the ability and intent to hold its equity securities until recovery; therefore, the Company does not consider its fixed income investments or equity securities to be other-than-temporarily impaired at September 30, 2015 . Other Investments The Company is involved in the normal course of business with variable interest entities ("VIEs") as a passive investor in residential and commercial mortgage-backed securities and through its interests in various other investments that are structured as limited partnerships considered to be third party VIEs. The Company determines whether it is the primary beneficiary of an entity subject to consolidation based on a qualitative assessment of the VIE's capital structure, contractual terms, nature of the VIE's operations and purpose and the Company's relative exposure to the related risks of the VIE on the date it becomes initially involved in the VIE. The Company reassesses its VIE determination with respect to an entity on an ongoing basis. The Company determined that it was not the primary beneficiary for any of these investments as of September 30, 2015 . The Company believes its exposure to loss with respect to these investments is generally limited to the investment carrying amounts reported in the Company's Unaudited Condensed Consolidated Balance Sheets and any unfunded investment commitments. Collateralized Reinsurance Entities As of September 30, 2015, the Company owned 33.3% of the BCRH's common shares. BCRH is considered a VIE under U.S. generally accepted accounting principles ("U.S. GAAP") and the Company has determined that it is BCRH's primary beneficiary. As a result, the Company fully consolidates the assets, liabilities and operations of BCRH and its subsidiaries within its Unaudited Condensed Consolidated Financial Statements. The interests in BCRH and its subsidiaries that the Company fully consolidates that are attributable to third-party investors are reported within the Company's Unaudited Condensed Consolidated Financial Statements as non-controlling interests. The Company reassesses its VIE determination with respect to BCRH on an ongoing basis. As of September 30, 2015, the Company owned 25.1% of the BCGR Listed Fund's ordinary shares. The BCGR Listed Fund is considered a "voting interest entity" under U.S. GAAP and, because the Company owns less than 50% of its outstanding ordinary shares, the Company does not consolidate the BCGR Listed Fund's assets, liabilities or operations within its consolidated financial statements. However, the BCGR Cell and Blue Water Re Ltd. ("Blue Water Re"), the Company's wholly-owned Bermuda-based special purpose insurance vehicle, are considered VIEs under U.S. GAAP and the Company has determined that it is the primary beneficiary of these entities. Therefore, as funds held in the BCGR Listed Fund are deployed into the BCGR Cell, and ultimately into Blue Water Re, they are included in the Company's consolidated financial statements. Conversely, as funds previously deployed by the BCGR Listed Fund and the BCGR Cell into Blue Water Re are returned to the BCGR Listed Fund, they are no longer included in the Company's consolidated financial statements. The interests in the BCGR Cell and Blue Water Re that the Company fully consolidates which are attributable to third-party investors are reported within the Company's consolidated financial statements as non-controlling interests. The Company reassesses its VIE determinations with respect to the BCGR Cell and Blue Water Re on an ongoing basis. 3. Investments, cont'd. The following table summarizes the movements in the non-controlling interests balance during the three months ended September 30, 2015 : Three Months Ended September 30, 2015 Non-controlling interests acquired July 31, 2015 $ 258,529 Income attributable to third-party investments in the BCGR Cell 821 Income attributable to third-party investments in BCRH 1,886 Net income attributable to non-controlling interests 2,707 Net third-party investments in BCRH (7 ) Dividends declared by BCRH attributable to non-controlling interests (1,755 ) Non-controlling interests - ending balance $ 259,474

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurement	4. Fair value measurement The Company determines the fair value of the fixed maturity investments, short-term investments, equity securities, other investments, debt, and other assets and liabilities in accordance with current accounting guidance, which defines fair value and establishes a fair value hierarchy based on inputs to the various valuation techniques used for each fair value measurement. The Company determines the estimated fair value of each individual security utilizing the highest level inputs available. Valuation inputs by security type may include the following: • Government and agencies fixed maturity securities – These securities are generally priced by pricing services or index providers. The pricing services or index providers may use current market trades for securities with similar quality, maturity and coupon. If no such trades are available, the pricing service typically uses analytical models which may incorporate option adjusted spreads, daily interest rate data and market/sector news. The Company generally classifies the fair values of government and agencies securities in Level 2. Current issue U.S. government securities are generally valued based on Level 1 inputs, which use the market approach valuation technique. • Government guaranteed corporate fixed maturity securities – These securities are generally priced by pricing services or index providers. The pricing service or index providers may use current market trades for securities with similar quality, maturity and coupon. If no such trades are available, the pricing service typically uses analytical spread models which may incorporate inputs from the U.S. treasury curve or LIBOR. The Company generally classifies the fair values of its government guaranteed corporate securities in Level 2. • Corporate fixed maturity securities – These securities are generally priced by pricing services or index providers. The pricing services or index providers typically use discounted cash flow models that incorporate benchmark curves for treasury, swap and high issuance credits. Credit spreads are developed from current market observations for like or similar securities. The Company generally classifies the fair values of its corporate securities in Level 2. • Equity securities – These securities are generally priced by pricing services or index providers. Depending on the type of underlying equity security or equity fund, the securities are priced by pricing services or index providers based on quoted market prices in active markets or through a discounted cash flow model that incorporates benchmark curves for treasury, swap and credits for like or similar securities. The Company generally classifies the fair values of its equity securities in Level 1 or 2. 4. Fair value measurement, cont'd. • Other assets and liabilities – A portion of other assets and liabilities are composed of a variety of derivative instruments used to enhance the efficiency of the investment portfolio and economically hedge certain risks. These instruments are generally priced by pricing services, broker/dealers and/or recent trading activity. The market value approach valuation technique is used to estimate the fair value for these derivatives based on significant observable market inputs. Certain derivative instruments are priced by pricing services based on quoted market prices in active markets. These derivative instruments are generally classified in Level 1. Other derivative instruments are priced using industry valuation models and are considered Level 2, as the inputs to the valuation model are based on observable market inputs. Also included in this line item are proprietary, non-exchange traded derivative-based risk management products primarily used to address weather and energy risks. The trading market for these weather derivatives are generally linked to energy and agriculture commodities, weather and other natural phenomena. In instances where market prices are not available, the Company uses industry or internally developed valuation techniques such as spread option, Black Scholes, quanto and simulation modeling to determine fair value and classifies these in Level 3. These models may reference prices for similar instruments. • Structured securities including agency and non-agency, residential and commercial, mortgage and asset-backed securities and collateralized loan and debt obligations – These securities are generally priced by broker/dealers. Broker/dealers may use current market trades for securities with similar qualities. If no such trades are available, inputs such as bid and offer, prepayment speeds, the U.S. treasury curve, swap curve and cash settlement may be used in a discounted cash flow model to determine the fair value of a security. The Company generally classifies the fair values of its structured securities in Level 2. • Other investments – Other investments are comprised of alternative funds and specialty funds and are generally priced on net asset values ("NAV") received from the fund managers or administrators. Due to the timing of the delivery of the final NAV by certain of the fund managers, valuations of certain alternative funds and specialty funds are estimated based on the most recently available information, including period end NAVs, period end estimates, or, in some cases, prior month or prior quarter NAVs. As this valuation technique incorporates both observable and significant unobservable inputs, the Company generally classifies the fair value of its other investments in Level 3. • Debt – Outstanding debt consists of the Company's 6.15% Senior Notes due October 15, 2015 (which were repaid by the Company upon maturity), the 7.0% Senior Notes due July 15, 2034, the 4.7% Senior Notes due October 15, 2022 (the "Senior Notes") and the Trust Preferred Securities. The fair values of these securities were obtained from a third party pricing service and pricing was based on the spread above the risk-free yield curve. These spreads are generally obtained from the new issue market, secondary trading and broker-dealer quotes. As these spreads and the yields for the risk-free yield curve are observable market inputs, the fair values of the Senior Notes and the Trust Preferred Securities are classified in Level 2. The carrying values of cash and cash equivalents, accrued investment income, net receivable on sales of investments, net payable on purchases of investments, the amount outstanding under the BCRH Credit Agreement and other financial instruments not described above approximated their fair values at September 30, 2015 and December 31, 2014 . Transfers between levels are assumed to occur at the end of each period. 4. Fair value measurement, cont'd. The following table sets forth the Company's fixed maturity investments, equity securities, short-term investments, other investments, other assets and liabilities and debt categorized by the level within the hierarchy in which the fair value measurements fall at September 30, 2015 : Fair Value Measurements at September 30, 2015 Total at September 30, 2015 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Fixed maturity investments U.S. government and agencies securities $ 806,143 $ 48,589 $ 757,554 $ — U.S. state and municipal securities 28,936 — 28,936 — Foreign government securities 157,212 — 157,212 — Government guaranteed corporate securities 65,930 — 65,930 — Corporate securities 1,878,766 — 1,750,877 127,889 Residential mortgage-backed securities 1,222,805 — 1,222,680 125 Commercial mortgage-backed securities 837,772 — 835,321 2,451 Collateralized loan and debt obligations 418,875 — 415,964 2,911 Asset-backed securities 611,736 — 611,736 — Total fixed maturity investments 6,028,175 48,589 5,846,210 133,376 Equity securities Equity investments 369,525 239,188 130,337 — Emerging market debt funds 58,853 — 58,853 — Convertible funds 45,854 — 45,854 — Preferred equity investments 19,028 — 19,028 — Short-term fixed income fund 4,925 4,925 — — Total equity securities 498,185 244,113 254,072 — Short-term investments 364,938 — 364,938 — Other investments 842,446 — — 842,446 Other assets (see Note 7) 80,395 — 60,218 20,177 Total assets $ 7,814,139 $ 292,702 $ 6,525,438 $ 995,999 Liabilities Other liabilities (see Note 7) $ 53,534 $ — $ 33,809 $ 19,725 Debt 968,248 — 968,248 — Total liabilities $ 1,021,782 $ — $ 1,002,057 $ 19,725 During the three months ended September 30, 2015 , $128.9 million of investments, consisting primarily of corporate securities and $232.1 million of other investments acquired from Montpelier were transferred into Level 3 as no observable inputs were available. No securities were transferred out of Level 3 to Level 2 during the period. During the nine months ended September 30, 2015 , $130.9 million of investments, consisting primarily of corporate securities and $232.1 million of other investments acquired from Montpelier were transferred into Level 3 as no observable inputs were available, and $9.2 million of primarily asset-backed and commercial mortgage-backed securities were transferred out of Level 3 to Level 2 during the period as market activity for these securities increased and observable inputs became available. 4. Fair value measurement, cont'd. The following table sets forth the Company’s fixed maturity investments, equity securities, short-term investments, other investments, other assets and liabilities and debt categorized by the level within the hierarchy in which the fair value measurements fall at December 31, 2014 : Fair Value Measurements at December 31, 2014 Total at December 31, 2014 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Fixed maturity investments U.S. government and agencies securities $ 587,411 $ 105,121 $ 482,290 $ — U.S. state and municipal securities 39,413 — 39,413 — Foreign government securities 240,536 — 240,536 — Government guaranteed corporate securities 48,102 — 48,102 — Corporate securities 1,361,462 — 1,358,960 2,502 Residential mortgage-backed securities 1,175,006 — 1,174,997 9 Commercial mortgage-backed securities 979,419 — 974,602 4,817 Collateralized loan and debt obligations 248,011 — 246,042 1,969 Asset-backed securities 413,221 — 410,228 2,993 Total fixed maturity investments 5,092,581 105,121 4,975,170 12,290 Equity securities Equity investments 202,535 138,463 64,072 — Emerging market debt funds 60,150 — 60,150 — Convertible funds 46,111 — 46,111 — Preferred equity investments 15,836 — 15,836 — Short-term fixed income fund 6,736 6,736 — — Total equity securities 331,368 145,199 186,169 — Short-term investments 9,014 — 9,014 — Other investments 541,454 — — 541,454 Other assets (see Note 7) 99,504 — 73,889 25,615 Total assets $ 6,073,921 $ 250,320 $ 5,244,242 $ 579,359 Liabilities Other liabilities (see Note 7) $ 54,338 $ — $ 18,972 $ 35,366 Debt 623,740 — 623,740 — Total liabilities $ 678,078 $ — $ 642,712 $ 35,366 Level 3 assets represented 12.7% and 9.5% of the Company's total available for sale and trading investments, other investments and derivative instruments at September 30, 2015 and December 31, 2014 , respectively. Level 3 securities are primarily comprised of corporate securities, mortgage-backed securities, collateralized loan and debt obligations, asset-backed securities, investments in alternative and specialty funds, classified as other investments, and weather derivatives. The NAV used to measure the fair value of the Company's other investments are generally derived from the underlying investments held within the funds. Although the Company does not have direct access to detailed financial information related to the underlying investments of the funds, the Company obtains and reviews fund financial statements, internal control review reports, and industry benchmarking reports to determine the reasonability of the NAV of the funds. There were no material changes in the Company's valuation techniques for the nine months ended September 30, 2015 . 4. Fair value measurement, cont'd. Other assets and other liabilities measured at fair value at September 30, 2015 include assets of $20.2 million ( 2014 - $25.6 million ) and liabilities of $19.7 million ( 2014 - $35.4 million ) related to proprietary, non-exchange traded derivative-based risk management products used in the Company's weather risk management business, and hedging and trading activities related to these risks. In instances where market prices are not available, the Company may use industry or internally developed valuation techniques such as historical analysis and simulation modeling to determine fair value and are considered Level 3. Observable and unobservable inputs to these valuation techniques vary by contract requirements and commodity type, are validated using market-based or independently sourced parameters where applicable and may include the following: • Observable inputs: contract price, notional, option strike, term to expiry, interest rate, contractual limits; • Unobservable inputs: correlation; and • Both observable and unobservable: forward commodity price, forward weather curve. The Company's weather curves are determined by taking the average payouts for each transaction within its portfolio utilizing de-trended historical weather measurements. The Company's commodity curves are determined using historical market data scaled to currently observed market prices. The range of each unobservable input could vary based on the specific commodity, including, but not limited to natural gas, electricity, crude, liquids, temperature or precipitation. Due to the diversity of the portfolio, the range of unobservable inputs could be wide-spread as reflected in the below table on quantitative information. If a trade has one or more significant valuation inputs that are unobservable, such trades are initially valued at the transaction price, which is considered to be the best initial estimate of fair value. Subsequent to the initial valuation, the Company updates market observable inputs to reflect observable market changes. The unobservable inputs are validated at each reporting period and are only changed when corroborated by evidence such as similar market transactions, third-party pricing services and/or broker or dealer quotations or other empirical market data. Changes in any or all of the unobservable inputs listed above may contribute positively or negatively to the overall portfolio fair value depending upon the underlying position. In general, movements in weather curves are the largest contributing factor that impacts fair value. 4. Fair value measurement, cont'd. Below is a summary of quantitative information regarding the significant unobservable inputs used in determining the fair value of the net weather and energy related derivative assets and liabilities classified in Level 3 that are measured at fair value on a recurring basis at September 30, 2015 and December 31, 2014 : September 30, 2015 Fair Value (Level 3) Valuation Techniques Unobservable Inputs Low High Weighted Average or Actual (U.S. dollars in thousands, except for correlation) Net weather and energy related derivative assets $ 452 Historical Analysis and Simulation Correlation 0 1 Actual Weather curve $ 2,200 $ 10,600 Actual Commodity curve $ — $ 13 Actual December 31, 2014 Fair Value (Level 3) Valuation Techniques Unobservable Inputs Low High Weighted Average or Actual (U.S. dollars in thousands, except for correlation) Net weather and energy related derivative liabilities $ 9,751 Historical Analysis and Simulation Correlation 0 1 Actual Weather curve $ (828 ) $ 2,500 Actual Commodity curve $ — $ 13 Actual There were no impairment losses on Level 3 securities recognized in earnings for the three and nine months ended September 30, 2015 or 2014 . 4. Fair value measurement, cont'd. The following tables present a reconciliation of the beginning and ending balances for all assets and liabilities measured at fair value on a recurring basis using Level 3 inputs during the three months ended September 30, 2015 and 2014 : Three Months Ended September 30, 2015 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 4,707 $ 623,868 $ 23,691 $ 652,266 $ (22,184 ) Total equity income and realized gains included in earnings — 10,031 — 10,031 — Total equity losses and losses included in earnings (24 ) (22,463 ) — (22,487 ) — Total income included in other underwriting income (loss) — — 1,589 1,589 14,745 Total loss included in other underwriting income (loss) — — (11,794 ) (11,794 ) (2,552 ) Change in unrealized gains included in other comprehensive (loss) income 85 — — 85 — Change in unrealized losses included in other comprehensive (loss) income (35 ) — — (35 ) — Purchases — 12,116 1,250 13,366 (737 ) Issues — — 5,441 5,441 (9,058 ) Sales (237 ) (13,243 ) — (13,480 ) — Settlements — — — — 61 Transfers in to Level 3 128,880 232,137 — 361,017 — Transfers out of Level 3 — — — — — Level 3, end of period $ 133,376 $ 842,446 $ 20,177 $ 995,999 $ (19,725 ) Three Months Ended September 30, 2014 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 9,515 $ 648,642 $ 10,992 $ 669,149 $ (10,284 ) Total equity income and realized gains included in earnings 9 10,913 — 10,922 — Total equity losses and losses included in earnings (6 ) (12,698 ) — (12,704 ) — Total income included in other underwriting income (loss) — — 3,180 3,180 4,794 Total loss included in other underwriting income (loss) — — (5,235 ) (5,235 ) (3,719 ) Change in unrealized gains included in other comprehensive (loss) income 245 — — 245 — Change in unrealized losses included in other comprehensive (loss) income (104 ) — — (104 ) — Purchases 842 26,190 1,501 28,533 (751 ) Issues — — 7,331 7,331 (10,917 ) Sales (545 ) (14,369 ) — (14,914 ) — Settlements — — (2,947 ) (2,947 ) 4,961 Transfers in to Level 3 2,198 — — 2,198 — Transfers out of Level 3 (4,961 ) — — (4,961 ) — Level 3, end of period $ 7,193 $ 658,678 $ 14,822 $ 680,693 $ (15,916 ) 4. Fair value measurement, cont'd. The following tables present a reconciliation of the beginning and ending balances for all assets and liabilities measured at fair value on a recurring basis using Level 3 inputs during the nine months ended September 30, 2015 and 2014 : Nine Months Ended September 30, 2015 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 12,290 $ 541,454 $ 25,615 $ 579,359 $ (35,366 ) Total equity income and realized gains included in earnings 113 45,049 — 45,162 — Total equity losses and losses included in earnings (35 ) (41,523 ) — (41,558 ) — Total income included in other underwriting income (loss) — — 7,184 7,184 35,610 Total loss included in other underwriting income (loss) — — (24,788 ) (24,788 ) (9,772 ) Change in unrealized gains included in other comprehensive (loss) income 109 — — 109 — Change in unrealized losses included in other comprehensive (loss) income (228 ) — — (228 ) — Purchases — 115,095 1,250 116,345 (737 ) Issues — — 17,774 17,774 (27,806 ) Sales (547 ) (49,766 ) — (50,313 ) — Settlements — — (6,858 ) (6,858 ) 18,346 Transfers in to Level 3 130,850 232,137 — 362,987 — Transfers out of Level 3 (9,176 ) — — (9,176 ) — Level 3, end of period $ 133,376 $ 842,446 $ 20,177 $ 995,999 $ (19,725 ) Nine Months Ended September 30, 2014 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 7,328 $ 617,478 $ 14,038 $ 638,844 $ (19,569 ) Total equity income and realized gains included in earnings 62 46,385 — 46,447 — Total equity losses and losses included in earnings (32 ) (23,844 ) — (23,876 ) — Total income included in other underwriting income (loss) — — 18,396 18,396 24,842 Total loss included in other underwriting income (loss) — — (23,845 ) (23,845 ) (20,672 ) Change in unrealized gains included in other comprehensive income (loss) 445 — — 445 — Change in unrealized losses included in other comprehensive income (loss) (255 ) — — (255 ) — Purchases 842 52,731 1,501 55,074 (751 ) Issues — — 10,912 10,912 (18,080 ) Sales (1,585 ) (34,072 ) — (35,657 ) — Settlements — — (6,180 ) (6,180 ) 18,314 Transfers in to Level 3 7,201 — — 7,201 — Transfers out of Level 3 (6,813 ) — — (6,813 ) — Level 3, end of period $ 7,193 $ 658,678 $ 14,822 $ 680,693 $ (15,916 )

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Earnings Per Share	5. Earnings per share The two-class method utilized by the Company is an earnings allocation formula that determines earnings per share for the holders of Endurance Holdings' ordinary shares (also referred to as "common shares") and participating common shares, which includes unvested restricted shares and restricted share units that receive cash dividends, according to dividends declared and participation rights in undistributed earnings. Net income available to Endurance Holdings common and participating common shareholders is reduced by the amount of dividends declared in the current period and by the contractual amount of dividends that must be paid for the current period related to the Company's common and participating common shares. Any remaining undistributed earnings are allocated to the common and participating common shareholders to the extent that each security may share in earnings as if all of the earnings for the period had been distributed. In periods of loss, no losses are allocated to participating common shareholders. Instead, all such losses are allocated solely to the common shareholders. Basic earnings per Endurance Holdings common share are calculated by dividing net income available to common shareholders by the weighted average number of common shares outstanding. The weighted average number of common shares excludes any dilutive effect of outstanding options and convertible securities such as unvested restricted shares and restricted share units. Diluted earnings per Endurance Holdings common share are based on the weighted average number of common shares and assumes the exercise of all dilutive stock options and the vesting or conversion of all convertible securities such as unvested restricted shares and restricted share units using the two-class method described above. The following table sets forth the computation of basic and diluted earnings per Endurance Holdings common share for the three and nine months ended September 30, 2015 and 2014 : Three Months Ended Nine Months Ended 2015 2014 2015 2014 Numerator: Net income available to Endurance Holdings common and participating common shareholders $ 43,635 $ 68,046 $ 219,944 $ 239,313 Less amount allocated to participating common shareholders (1) (1,251 ) (1,930 ) (6,442 ) (6,907 ) Net income allocated to Endurance Holdings common shareholders $ 42,384 $ 66,116 $ 213,502 $ 232,406 Denominator: Weighted average shares - basic 57,923,044 43,464,790 48,453,368 43,332,461 Share equivalents: Options 111,760 45,625 137,366 23,237 Restricted shares and restricted share units 11,344 — 1,367 94 Weighted average shares - diluted 58,046,148 43,510,415 48,592,101 43,355,792 Basic earnings per Endurance Holdings common share $ 0.73 $ 1.52 $ 4.41 $ 5.36 Diluted earnings per Endurance Holdings common share $ 0.73 $ 1.52 $ 4.39 $ 5.36 (1) Represents earnings attributable to holders of unvested restricted shares and restricted share units issued under the Company's equity compensation plan that are considered participating. In periods of loss, no losses are allocated to participating common shareholders (unvested restricted shares and restricted share units). 5. Earnings per share, cont'd. Endurance Holdings declared a dividend of $0.484375 per Series A preferred share and $0.468750 per Series B preferred share on August 17, 2015 ( 2014 - Series A: $0.484375 , Series B: $0.468750 ). The Series A and Series B preferred share dividends were paid on September 15, 2015 to shareholders of record on August 31, 2015 . Endurance Holdings also declared a dividend of $0.35 per common share on August 17, 2015 ( 2014 - $0.34 ). The dividend was paid on September 30, 2015 to shareholders of record on September 15, 2015 . Three Months Ended Nine Months Ended 2015 2014 2015 2014 Dividends declared per Series A preferred share $ 0.484375 $ 0.484375 $ 1.453125 $ 1.453125 Dividends declared per Series B preferred share $ 0.468750 $ 0.468750 $ 1.406250 $ 1.406250 Dividends declared per common share $ 0.35 $ 0.34 $ 1.05 $ 1.02

Accumulated Other Comprehensive

Accumulated Other Comprehensive (Loss) Income	9 Months Ended
	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive (Loss) Income	6. Accumulated other comprehensive (loss) income The following tables present the changes in accumulated other comprehensive (loss) income balances by component for the three months ended September 30, 2015 and 2014 : For the Three Months Ended September 30, 2015 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,722 ) $ 43,610 $ (4,923 ) $ 36,965 Other comprehensive (loss) income before reclassifications — (18,258 ) (15,625 ) (33,883 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) 22 (11,648 ) — (11,626 ) Net current period other comprehensive (loss) income 22 (29,906 ) (15,625 ) (45,509 ) Ending balance $ (1,700 ) $ 13,704 $ (20,548 ) $ (8,544 ) (1) All amounts are net of tax. For the Three Months Ended September 30, 2014 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,810 ) 106,989 $ 30,859 $ 136,038 Other comprehensive (loss) income before reclassifications — (25,446 ) (20,404 ) (45,850 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) 22 (8,911 ) — (8,889 ) Net current period other comprehensive (loss) income 22 (34,357 ) (20,404 ) (54,739 ) Ending balance $ (1,788 ) $ 72,632 $ 10,455 $ 81,299 (1) All amounts are net of tax. 6. Accumulated other comprehensive (loss) income, cont'd. The following tables present the changes in accumulated other comprehensive (loss) income balances by component for the nine months ended September 30, 2015 and 2014 : For the Nine Months Ended September 30, 2015 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,766 ) $ 86,100 $ (7,628 ) $ 76,706 Other comprehensive (loss) income before reclassifications — (35,195 ) (12,920 ) (48,115 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) 66 (37,201 ) — (37,135 ) Net current period other comprehensive (loss) income 66 (72,396 ) (12,920 ) (85,250 ) Ending balance $ (1,700 ) $ 13,704 $ (20,548 ) $ (8,544 ) (1) All amounts are net of tax. For the Nine Months Ended September 30, 2014 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,855 ) $ 45,950 $ 18,636 $ 62,731 Other comprehensive (loss) income before reclassifications — 41,895 (8,181 ) 33,714 Amounts reclassified from accumulated other comprehensive (loss) income (1) 67 (15,213 ) — (15,146 ) Net current period other comprehensive (loss) income 67 26,682 (8,181 ) 18,568 Ending balance $ (1,788 ) $ 72,632 $ 10,455 $ 81,299 (1) All amounts are net of tax. 6. Accumulated other comprehensive (loss) income, cont'd. The following tables present the significant items reclassified out of accumulated other comprehensive (loss) income during the three months ended September 30, 2015 and 2014 : Three Months Ended September 30, 2015 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 22 Interest expense 22 Total before income taxes — Income tax expense $ 22 Total net of income taxes Unrealized gains on available for sale securities $ (11,871 ) Net realized and unrealized gains 38 Net impairment losses recognized in earnings (11,833 ) Total before income taxes 185 Income tax expense $ (11,648 ) Total net of income taxes Three Months Ended September 30, 2014 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 22 Interest expense 22 Total before income taxes — Income tax expense $ 22 Total net of income taxes Unrealized gains on available for sale securities $ (9,208 ) Net realized and unrealized gains 102 Net impairment losses recognized in earnings (9,106 ) Total before income taxes 195 Income tax expense $ (8,911 ) Total net of income taxes 6. Accumulated other comprehensive (loss) income, cont'd. The following tables present the significant items reclassified out of accumulated other comprehensive (loss) income during the nine months ended September 30, 2015 and 2014 : Nine Months Ended September 30, 2015 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 66 Interest expense 66 Total before income taxes — Income tax expense $ 66 Total net of income taxes Unrealized gains on available for sale securities $ (39,230 ) Net realized and unrealized gains 1,111 Net impairment losses recognized in earnings (38,119 ) Total before income taxes 918 Income tax expense $ (37,201 ) Total net of income taxes Nine Months Ended September 30, 2014 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 67 Interest expense 67 Total before income taxes — Income tax expense $ 67 Total net of income taxes Unrealized gains on available for sale securities $ (15,539 ) Net realized and unrealized gains 411 Net impairment losses recognized in earnings (15,128 ) Total before income taxes (85 ) Income tax benefit $ (15,213 ) Total net of income taxes

Derivatives

Derivatives	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	7. Derivatives The Company regularly transacts in certain derivative-based weather risk management products primarily to address weather and energy risks on behalf of third parties. The markets for these derivatives are generally linked to energy and agriculture commodities, weather and other natural phenomena. Generally, the Company's current portfolio of such derivative contracts is of short duration and such contracts are predominantly seasonal in nature. The Company also invests a portion of its investments with third party investment managers with investment guidelines that permit the use of derivative instruments. The Company may enter derivative transactions directly or as part of strategies employed by its external investment managers. The Company's derivative instruments are recorded in the Condensed Consolidated Balance Sheets at fair value, with changes in fair value and gains and losses recognized in net realized and unrealized gains, net foreign exchange losses and other underwriting income (loss) in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income. The Company's derivatives are not designated as hedges under current accounting guidance. The Company's objectives for holding these derivatives are as follows: Interest Rate Futures, Swaps, Swaptions and Options - to manage exposure to interest rate risk, which can include increasing or decreasing its exposure to this risk through modification of the portfolio composition and duration. Industry Loss Warranty ("ILW") Swaps - to manage underwriting risk. The Company has entered into ILW swap contracts which provide reinsurance-like protection to the Company for specific loss events associated with certain lines of its business. The Company has also sold ILW protection, which provides reinsurance-like protection to third parties for specific loss events. Foreign Exchange Forwards, Futures and Options - as part of overall currency risk management and investment strategies. Credit Default Swaps - to manage market exposures. The Company may assume or economically hedge credit risk through credit default swaps to replicate or hedge investment positions. The original term of these credit default swaps is generally five years or less. To-Be-Announced Mortgage-backed Securities ("TBAs") - to enhance investment performance and as part of overall investment strategy. TBAs represent commitments to purchase or sell a future issuance of agency mortgage-backed securities. For the period between purchase of a TBA and issuance of the underlying securities, the Company’s position is accounted for as a derivative. Energy and Weather Contracts – to address weather and energy risks. The Company may purchase or sell contracts with financial settlements based on the performance of an index linked to a quantifiable weather element, such as temperature, precipitation, snowfall or windspeed, and structures with multiple risk triggers indexed to a quantifiable weather element and a weather sensitive commodity price, such as temperature and electrical power or natural gas. Generally, the Company’s current portfolio of energy and weather derivative contracts is of comparably short duration and such contracts are predominantly seasonal in nature. LIBOR Swap – to establish future net cash flows in connection with the Trust Preferred Securities for the five -year period beginning March 30, 2012 as if these securities bore interest at a fixed rate of 4.905% . See Note 12, Debt and financing arrangements. 7. Derivatives, cont'd. The fair values and the related notional values of derivatives at September 30, 2015 and December 31, 2014 are shown below. September 30, 2015 December 31, 2014 Fair Value Notional Principal Amount Fair Value Notional Principal Amount Derivatives recorded in other assets Foreign exchange forward contracts $ 663 $ 49,845 $ 651 $ 42,694 Credit default swaps 17 4,290 — — Interest rate swaps 156 4,000 — — Interest rate futures 8 54,659 7 7,595 ILWs 536 12,500 — — TBAs 58,838 55,000 73,231 70,000 Energy and weather contracts 20,177 70,143 25,615 81,624 Total recorded in other assets $ 80,395 $ 99,504 Derivatives recorded in other liabilities Foreign exchange forward contracts $ 418 $ 24,832 $ 123 $ 20,945 Credit default swaps 322 6,600 — — Interest rate swaps 198 40,100 20 12,549 Interest rate swaptions — — 9 13,100 Interest rate futures 3 9,762 — — ILWs 1,120 19,500 — — LIBOR swap 738 100,000 — — TBAs 31,010 29,000 18,820 18,000 Energy and weather contracts 19,725 112,435 35,366 135,050 Total recorded in other liabilities $ 53,534 $ 54,338 Net derivative asset $ 26,861 $ 45,166 At September 30, 2015 , the Company's derivative assets of $80.4 million ( December 31, 2014 - $99.5 million ) and liabilities of $53.5 million ( December 31, 2014 - $54.3 million ) are subject to master netting agreements, which provide for the ability to settle the derivative asset and liability with each counterparty on a net basis. At September 30, 2015 and December 31, 2014 , interest rate futures were not subject to a master netting agreement. At September 30, 2015 and December 31, 2014 , the Company's other derivative instruments were recorded on a gross basis in the Unaudited Condensed Consolidated Balance Sheets. 7. Derivatives, cont'd. The gains and losses on the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income for derivatives for the three and nine months ended September 30, 2015 and 2014 were as follows: Three Months Ended Nine Months Ended 2015 2014 2015 2014 Total gain included in net foreign exchange losses from foreign exchange forward contracts $ 155 $ 1,214 $ 1,281 $ 815 Interest rate futures (78 ) — 17 136 Credit default swaps (143 ) 6 (134 ) 20 Interest rate swaps (705 ) 384 (940 ) (698 ) Interest rate swaptions 28 (3 ) 56 425 ILWs (652 ) — (652 ) — LIBOR swap (173 ) — (173 ) — TBAs (82 ) 193 531 2,649 Total (losses) gains included in net realized and unrealized gains (1,805 ) 580 (1,295 ) 2,532 Total gain included in other underwriting income (loss) from energy and weather contracts 1,988 1,784 8,030 1,486 Total gains from derivatives $ 338 $ 3,578 $ 8,016 $ 4,833

Stock-Based Employee Compensati

Stock-Based Employee Compensation And Other Stock Plans	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Employee Compensation And Other Stock Plans	8. Stock-based employee compensation and other stock plans The Company has a stock-based employee compensation plan, which provides the Company with the ability to grant options to purchase the Company's ordinary shares, share appreciation rights, restricted shares, restricted share units, share bonuses and other equity incentive awards to key employees. Options In 2013, the Company issued options to the current Chief Executive Officer as an inducement to his joining the Company. The options vest annually, in five equal tranches commencing on May 28, 2013, subject to the Chief Executive Officer's continued employment, or in the event of certain terminations of employment and other events. The Chief Executive Officer's options have a ten -year contractual life. The Company uses the Black-Scholes-Merton formula to estimate the value of stock options granted. Performance-Based Restricted Shares Commencing in March 2015, the Company issued performance-based restricted shares to certain of its senior executives under its 2007 Equity Incentive Plan (the "2007 Plan"). The performance-based restricted shares represent the right to receive a specified number of ordinary shares in the future, based upon the achievement of pre-established performance criteria during the applicable performance period. Performance-based restricted shares granted to employees vest three years after the date of grant. The number of performance-based restricted shares that will ultimately vest is based upon the actual performance of the Company compared to the performance of a peer group of publicly-traded companies. Performance-based restricted shares are forfeited upon departure from the Company for any reason prior to the applicable vesting date other than in cases of death, disability, termination of employment in connection with a change in control or retirement. In the case of death, disability or change in control, 50% of the performance-based restricted shares will vest upon the date of death or disability or termination of employment in connection with a change in control. Where an employee meets certain retirement eligibility criteria, the performance-based restricted shares will continue to vest post-employment, subject to compliance with certain non-competition obligations. The fair value of the performance-based restricted shares is measured at the grant date using a Monte Carlo simulation based on pre-established targets relating to certain performance based measures achieved by the Company, with the associated expense recognized over the applicable performance and vesting period. 8. Stock-based employee compensation and other stock plans, cont'd. Time-Based Restricted Shares The Company has issued time-based restricted shares to employees and non-employee directors of the Company's Board of Directors under the 2007 Plan. Restricted shares granted to employees generally vest pro-rata over a four -year period. Restricted shares are forfeited upon departure from the Company for any reason prior to the applicable vesting date other than in cases where an employee meets certain retirement eligibility criteria that allow for continuing post-employment vesting of restricted shares, subject to compliance with certain non-competition obligations. Restricted shares granted to non-employee directors vest twelve months following the date of grant and are forfeited upon departure of the non-employee director from the Company's Board of Directors for any reason prior to the applicable vesting date. The fair value of the restricted shares granted is equal to the fair market value of the Company's ordinary shares on the grant date. Compensation equal to the fair market value of the restricted shares at the measurement date is amortized and charged to income over the vesting period. Restricted Share Units The Company has issued restricted share units to employees in select jurisdictions where the issuance of restricted shares results in unfavorable tax treatment for employee recipients. Restricted share units granted to employees generally vest pro-rata over a four -year period. Restricted share units are forfeited upon departure from the Company for any reason prior to the applicable vesting date other than in cases where an employee meets certain retirement eligibility criteria that allow for continuing post-employment vesting of restricted shares, subject to compliance with certain non-competition obligations. On July 31, 2015, following the completion of the Company's acquisition of Montpelier, outstanding Montpelier restricted share units were assumed by the Company and adjusted to represent the right to receive 0.472 of the Company's ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of the Company's ordinary shares. The fair value of the restricted share units granted or assumed is equal to the fair market value of the Company's ordinary shares on the grant or assumption date, as applicable. Compensation equal to the fair market value of the restricted share units at the measurement date is amortized and charged to income over the vesting period. Summary of Stock-Based Employee Compensation Activity No options were granted, vested or expired during the quarters ended September 30, 2015 or September 30, 2014 . During the quarter ended September 30, 2015 , 480,000 options were exercised. No options were exercised during the quarter ended September 30, 2014 . The total intrinsic value of options exercised during the quarter ended September 30, 2015 was $9.5 million . The Company received proceeds of $23.1 million from the exercise of options during the quarter ended September 30, 2015 . The Company issued new ordinary shares in connection with the exercise of the above options. For the quarter ended September 30, 2015 , compensation costs recognized in earnings for all options totaled $0.3 million ( 2014 - $0.6 million ). At September 30, 2015 , compensation costs not yet recognized related to unvested stock options was $1.3 million ( 2014 - $3.2 million ). No options were granted or expired during the nine months ended September 30, 2015 or September 30, 2014 . During the nine months ended September 30, 2015 , 480,000 options were exercised. During the nine months ended September 30, 2014 , 15,000 options were exercised. During the nine months ended September 30, 2015 , 160,000 ( 2014 - 160,000 ) options vested. The total intrinsic value of options exercised during the nine months ended September 30, 2015 was $9.5 million . The Company received proceeds of $23.1 million from the exercise of options during the nine months ended September 30, 2015 . The total intrinsic value of options exercised during the nine months ended September 30, 2014 was $0.3 million . The Company received proceeds of $0.5 million from the exercise of options during the nine months ended September 30, 2014 . The Company issued new ordinary shares in connection with the exercise of the above options. For the nine months ended September 30, 2015 , compensation costs recognized in earnings for all options totaled $1.3 million ( 2014 - $2.5 million ). 8. Stock-based employee compensation and other stock plans, cont'd. A summary of the restricted share and restricted share unit activity during the nine months ended September 30, 2015 , is presented below: Number of Shares/Units Aggregate Intrinsic Value Unvested, beginning of period 1,290,894 Granted and assumed 1,360,981 Settled (776,614 ) Forfeited (17,701 ) Unvested, end of period 1,857,560 Outstanding, end of period 1,857,560 $ 113,367 During the quarter ended September 30, 2015 , the Company granted an aggregate of 14,703 ( 2014 – 39,080 ) restricted shares and restricted share units under the 2007 Plan, and assumed 841,926 (2014 - nil ) outstanding Montpelier restricted share units, adjusted to represent the right to receive 0.472 of the Company's ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of ordinary shares. The restricted shares and restricted share units granted and assumed had weighted average grant date fair values of $59.4 million ( 2014 - $2.1 million ). During the quarter ended September 30, 2015 , the aggregate fair value of restricted shares that vested was $23.0 million ( 2014 - $0.2 million ). For the quarter ended September 30, 2015 , compensation costs recognized in earnings for all restricted shares and restricted share units were $28.1 million ( 2014 - $5.7 million ), including $20.4 million related to RSUs assumed from Montpelier. At September 30, 2015 , compensation costs not yet recognized related to unvested restricted shares and restricted share units was $32.0 million ( 2014 - $27.7 million ). During the nine months ended September 30, 2015 , the Company granted an aggregate of 519,055 ( 2014 – 472,497 ) restricted shares and restricted share units under the 2007 Plan, and assumed 841,926 (2014 - nil ) outstanding Montpelier restricted share units, adjusted to represent the right to receive 0.472 of the Company's ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of ordinary shares. The restricted shares and restricted share units granted and assumed had weighted average grant date fair values of $89.4 million ( 2014 - $24.8 million ). During the nine months ended September 30, 2015 , the aggregate fair value of restricted shares and restricted share units that vested was $44.7 million ( 2014 - $18.7 million ), including $20.4 million related to RSUs assumed from Montpelier. For the nine months ended September 30, 2015 , compensation costs recognized in earnings for all restricted shares and restricted share units were $45.0 million ( 2014 - $21.5 million ). Employee Share Purchase Plan The Company also has an Employee Share Purchase Plan ("2005 Employee Share Purchase Plan" and subsequently "2015 Employee Share Purchase Plan") under which employees of Endurance Holdings and certain of its subsidiaries may purchase the Company's ordinary shares. For the three and nine months ended September 30, 2015 , total expenses related to the Company’s 2005 and 2015 Employee Share Purchase Plans were approximately $76,000 ( 2014 - $62,000 ) and $220,000 ( 2014 - $172,000 ), respectively. The 2005 Employee Share Purchase Plan was scheduled to terminate in accordance with its terms on October 1, 2015. On February 26, 2015, the Compensation Committee of the Company's Board of Directors approved a new employee share purchase plan ("2015 Employee Share Purchase Plan"), which was approved by the Company's shareholders at its Annual General Meeting of Shareholders held on May 20, 2015. The Company ceased offering and issuing new shares under the 2005 Employee Share Purchase Plan on June 30, 2015 and began offering and issuing new shares under the 2015 Employee Share Purchase Plan after July 1, 2015.

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment Reporting	9. Segment reporting The determination of the Company's business segments is based on how the Company monitors the performance of its underwriting operations. The Company has two reportable business segments, Insurance and Reinsurance, which are comprised of the following lines of business: Insurance segment lines of business • Agriculture • Casualty and other specialty • Professional lines • Property, marine and energy Reinsurance segment lines of business • Catastrophe • Property • Casualty • Professional lines • Specialty Management measures Insurance and Reinsurance segment results on the basis of the combined ratio, which is obtained by dividing the sum of the net losses and loss expenses, acquisition expenses and general and administrative expenses by net premiums earned. When purchased within a single line of business, ceded reinsurance and recoveries are accounted for within that line of business. When purchased across multiple lines of business, ceded reinsurance and recoveries are allocated to the lines of business in proportion to the related risks assumed. The Company does not manage its assets by segment; accordingly, investment income and total assets are not allocated to the individual business segments. General and administrative expenses incurred by the segments are allocated directly. Remaining general and administrative expenses not incurred by the segments are classified as corporate expenses and are not allocated to the individual business segments. Ceded reinsurance and recoveries are recorded within the business segment to which they apply. The underwriting results of Montpelier are included in the Company's segment results from August 1, 2015. 9. Segment reporting, cont'd. The following table provides a summary of segment revenues, results, reserves for losses and loss expenses and goodwill for the three months ended September 30, 2015 : Three Months Ended September 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 448,563 $ 194,034 $ 642,597 Ceded premiums written (273,626 ) (32,281 ) (305,907 ) Net premiums written 174,937 161,753 336,690 Net premiums earned 234,143 322,860 557,003 Other underwriting income — 227 227 234,143 323,087 557,230 Expenses Net losses and loss expenses 139,141 124,852 263,993 Acquisition expenses 24,375 66,082 90,457 General and administrative expenses 31,880 28,913 60,793 195,396 219,847 415,243 Underwriting income $ 38,747 $ 103,240 141,987 Net investment income 16,533 Corporate expenses (74,308 ) Net foreign exchange losses (8,621 ) Net realized and unrealized gains 5,029 Net impairment losses recognized in earnings (38 ) Amortization of intangibles (11,318 ) Interest expense (12,324 ) Income before income taxes $ 56,940 Net loss ratio 59.5 % 38.6 % 47.4 % Acquisition expense ratio 10.4 % 20.5 % 16.2 % General and administrative expense ratio 13.6 % 9.0 % 24.3 % (1) Combined ratio 83.5 % 68.1 % 87.9 % Reserve for losses and loss expenses $ 2,442,821 $ 2,047,015 $ 4,489,836 Goodwill $ 85,179 $ 92,247 $ 177,426 (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses. 9. Segment reporting, cont'd. The following table provides a summary of segment revenues, results, reserves for losses and loss expenses and goodwill for the three months ended September 30, 2014 : Three Months Ended September 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 420,343 $ 205,767 $ 626,110 Ceded premiums written (222,704 ) (13,300 ) (236,004 ) Net premiums written 197,639 192,467 390,106 Net premiums earned 253,583 261,312 514,895 Other underwriting income — 2,123 2,123 253,583 263,435 517,018 Expenses Net losses and loss expenses 196,677 93,592 290,269 Acquisition expenses 20,170 73,222 93,392 General and administrative expenses 40,401 28,545 68,946 257,248 195,359 452,607 Underwriting (loss) income $ (3,665 ) $ 68,076 64,411 Net investment income 25,357 Corporate expenses (11,969 ) Net foreign exchange losses (783 ) Net realized and unrealized gains 9,788 Net impairment losses recognized in earnings (102 ) Amortization of intangibles (1,623 ) Interest expense (13,127 ) Income before income taxes $ 71,952 Net loss ratio 77.5 % 35.8 % 56.4 % Acquisition expense ratio 8.0 % 28.0 % 18.1 % General and administrative expense ratio 15.9 % 11.0 % 15.7 % (1) Combined ratio 101.4 % 74.8 % 90.2 % Reserve for losses and loss expenses $ 2,134,985 $ 1,762,498 $ 3,897,483 Goodwill $ 47,925 $ 43,401 $ 91,326 (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses. 9. Segment reporting, cont'd. The following table provides gross and net premiums written by line of business for the three months ended September 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 156,145 $ 29,634 $ 188,011 $ 103,536 Casualty and other specialty 128,509 64,490 115,895 50,750 Professional lines 80,069 37,479 62,631 20,216 Property, marine and energy 83,840 43,334 53,806 23,137 Total Insurance 448,563 174,937 420,343 197,639 Reinsurance Catastrophe 40,660 14,814 47,173 41,157 Property 53,423 52,887 73,807 73,807 Casualty 42,802 42,802 23,409 23,409 Professional lines 31,705 31,705 21,520 21,520 Specialty 25,444 19,545 39,858 32,574 Total Reinsurance 194,034 161,753 205,767 192,467 Total $ 642,597 $ 336,690 $ 626,110 $ 390,106 9. Segment reporting, cont'd. The following table provides a summary of the segment revenues and results for the nine months ended September 30, 2015 : Nine Months Ended September 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 1,653,647 $ 1,151,566 $ 2,805,213 Ceded premiums written (984,372 ) (160,114 ) (1,144,486 ) Net premiums written 669,275 991,452 1,660,727 Net premiums earned 571,467 833,530 1,404,997 Other underwriting income — 4,022 4,022 571,467 837,552 1,409,019 Expenses Net losses and loss expenses 359,136 315,915 675,051 Acquisition expenses 57,960 199,561 257,521 General and administrative expenses 89,289 81,359 170,648 506,385 596,835 1,103,220 Underwriting income $ 65,082 $ 240,717 305,799 Net investment income 90,646 Corporate expenses (99,210 ) Net foreign exchange losses (29,154 ) Net realized and unrealized gains 32,898 Net impairment losses recognized in earnings (1,111 ) Amortization of intangibles (14,496 ) Interest expense (30,445 ) Income before income taxes $ 254,927 Net loss ratio 62.9 % 37.9 % 48.1 % Acquisition expense ratio 10.1 % 23.9 % 18.3 % General and administrative expense ratio 15.6 % 9.8 % 19.2 % (1) Combined ratio 88.6 % 71.6 % 85.6 % (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses. 9. Segment reporting, cont'd. The following table provides a summary of the segment revenues and results for the nine months ended September 30, 2014 : Nine Months Ended September 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 1,394,145 $ 1,078,905 $ 2,473,050 Ceded premiums written (674,441 ) (98,371 ) (772,812 ) Net premiums written 719,704 980,534 1,700,238 Net premiums earned 616,167 776,532 1,392,699 Other underwriting loss — (3,939 ) (3,939 ) 616,167 772,593 1,388,760 Expenses Net losses and loss expenses 434,777 291,584 726,361 Acquisition expenses 47,559 196,591 244,150 General and administrative expenses 113,069 73,690 186,759 595,405 561,865 1,157,270 Underwriting income $ 20,762 $ 210,728 231,490 Net investment income 105,649 Corporate expenses (53,817 ) Net foreign exchange losses (4,066 ) Net realized and unrealized gains 18,071 Net impairment losses recognized in earnings (411 ) Amortization of intangibles (4,863 ) Interest expense (31,910 ) Income before income taxes $ 260,143 Net loss ratio 70.6 % 37.6 % 52.2 % Acquisition expense ratio 7.7 % 25.3 % 17.5 % General and administrative expense ratio 18.3 % 9.5 % 17.3 % (1) Combined ratio 96.6 % 72.4 % 87.0 % (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses. 9. Segment reporting, cont'd. The following table provides gross and net premiums written by line of business for the nine months ended September 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 785,073 $ 254,771 $ 796,445 $ 431,007 Casualty and other specialty 375,247 174,850 291,578 144,038 Professional lines 231,565 105,153 176,061 64,632 Property, marine and energy 261,762 134,501 130,061 80,027 Total Insurance 1,653,647 669,275 1,394,145 719,704 Reinsurance Catastrophe 304,900 190,579 332,193 243,531 Property 209,683 206,454 283,107 283,015 Casualty 149,032 149,032 139,266 137,669 Professional lines 209,803 209,803 131,256 131,256 Specialty 278,148 235,584 193,083 185,063 Total Reinsurance 1,151,566 991,452 1,078,905 980,534 Total $ 2,805,213 $ 1,660,727 $ 2,473,050 $ 1,700,238

Commitments And Contingencies

Commitments And Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	10. Commitments and contingencies Concentrations of credit risk. The Company's reinsurance recoverables on paid and unpaid losses at September 30, 2015 and December 31, 2014 amounted to $993.3 million and $889.1 million , respectively. At September 30, 2015 , substantially all reinsurance recoverables on paid and unpaid losses were due from the U.S. government or from reinsurers rated A- or better by A.M. Best Company Inc. or Standard & Poor's Corporation. At September 30, 2015 and December 31, 2014 , the Company held collateral of $320.5 million and $199.7 million , respectively, related to its ceded reinsurance agreements. Major production sources. The following table shows the percentage of net premiums written generated through the Company’s largest brokers for the nine months ended September 30, 2015 and 2014 , respectively: Broker 2015 2014 Marsh & McLennan Companies, Inc. 24.9 % 20.9 % Aon Benfield 15.8 % 15.4 % Willis Companies 12.8 % 14.2 % Total of largest brokers 53.5 % 50.5 % Letters of credit. As of September 30, 2015 , the Company had issued letters of credit of $205.1 million ( December 31, 2014 – $209.9 million ) under its credit facilities and letter of credit reimbursement agreements in favor of certain ceding companies to collateralize obligations. 10. Commitments and contingencies, cont'd. Investment commitments. As of September 30, 2015 and December 31, 2014 , the Company had pledged cash and cash equivalents and fixed maturity investments of $134.6 million and $130.6 million , respectively, in favor of certain ceding companies to collateralize obligations. As of September 30, 2015 and December 31, 2014 , the Company had also pledged $232.9 million and $240.0 million of its cash and fixed maturity investments as required to meet collateral obligations for $205.1 million and $209.9 million , respectively, in letters of credit outstanding under its credit facilities and letter of credit reimbursement agreements. In addition, as of September 30, 2015 and December 31, 2014 , cash and fixed maturity investments with fair values of $208.9 million and $205.2 million were on deposit with U.S. state regulators, respectively. The Company is subject to certain commitments with respect to other investments at September 30, 2015 and December 31, 2014 . See Note 3, Investments. Investment assets held in trust. Blue Water Re does not operate with a financial strength rating and, instead, fully collateralizes its reinsurance obligations through cash and cash equivalents held in trust funds established by Blue Water Re (the "Blue Water Trusts") for the benefit of ceding companies. As of September 30, 2015 , the fair value of all assets held in the Blue Water Trusts was $436.8 million , which met the minimum values required on that date. As of September 30, 2015 , Blue Capital Re had pledged $194.9 million of its cash and cash equivalents to trust accounts established for the benefit of Blue Water Re pursuant to the BW Retrocessional Agreement (see Note 13). These funds are included in the value of the Blue Water Trusts balance presented above. Blue Capital Re ILS fully collateralizes its insurance-linked security obligations through cash and cash equivalents held in trust funds established by Blue Capital Re ILS (the "Blue Capital Re ILS Trusts") for the benefit of third parties. As of September 30, 2015 , the fair value of all assets held in the Blue Capital Re ILS Trusts was $5.2 million , which met the minimum values required on that date. During the current quarter ended September 30, 2015, Endurance Bermuda established a multi-beneficiary reinsurance trust (the "Endurance Reinsurance Trust") domiciled in Delaware. The Endurance Reinsurance Trust was established as a means of providing statutory credit to Endurance Bermuda's U.S. cedants. As of September 30, 2015 , the fair value of all investments held in the Endurance Reinsurance Trust was $20.0 million , which met the minimum value required on that date. Endurance Bermuda is party to a second multi-beneficiary reinsurance trust (the "Reduced Collateral Trust") domiciled in Delaware. The Reduced Collateral Trust was established as a means of providing statutory credit to Endurance Bermuda's U.S. cedants in connection with a reduction in collateral requirements in certain states. As of September 30, 2015 , the fair value of all assets held in the Reduced Collateral Trust was $10.0 million , which met the minimum value required on that date. Montpelier Reinsurance Ltd. ("Montpelier Re") is party to a reinsurance trust (the "MUSIC Trust"). The MUSIC Trust was established as a means of providing statutory credit to Montpelier U.S. Insurance Company ("MUSIC") in support of the business retained in connection with the 2011 sale by Montpelier of MUSIC to Selective Insurance Group, Inc. As of September 30, 2015 , the fair value of all assets held in the MUSIC Trust was $21.5 million , which met the minimum value required on that date. Montpelier Re is party to a multi-beneficiary Reinsurance Trust (the "Montpelier Reinsurance Trust") domiciled in New York. The Montpelier Reinsurance Trust was established as a means of providing statutory credit to Montpelier Re’s U.S. cedants. As of September 30, 2015 , the fair value of all assets held in the Montpelier Reinsurance Trust was $345.8 million , which exceeded the minimum value required on that date. Montpelier Re is party to a second multi-beneficiary reinsurance trust (the "FL Trust") in connection with a reduction in its Florida's collateral requirements. As of September 30, 2015 , the fair value of all assets held in the FL Trust was $26.5 million , which exceeded the minimum value required on that date. The Company is party to a Lloyd's Deposit Trust Deed (the "Lloyd's Capital Trust") in order to meet Endurance Corporate Capital Limited's ongoing funds at Lloyd's ("FAL") requirements. The minimum value of cash and investments held by the Lloyd’s Capital Trust is determined on the basis of Endurance Corporate Capital Limited's Individual Capital Assessment, which is used to determine the required amount of FAL. As of September 30, 2015 , the fair value of all assets held in the Lloyd's Capital Trust was $211.8 million , which met the minimum value required on that date. 10. Commitments and contingencies, cont'd. Premiums received by Syndicate 5151 are required to be received into the Lloyd's Premiums Trust Funds (the "Premiums Trust Funds"). Under the Premiums Trust Funds' deeds, assets may only be used for the payment of claims and valid expenses for a stated period of time. As of September 30, 2015 , the fair value of all assets held in the Premiums Trust Funds was $261.2 million . The Company also held cash balances in Syndicate 5151 of $23.6 million . The Company's investment assets held in trust appear on the Company’s Condensed Consolidated Balance Sheets as cash and cash equivalents, fixed maturity investments and accrued investment income, as appropriate. Lloyd's New Central Fund. The Lloyd's New Central Fund is available to satisfy claims if a member of Lloyd's is unable to meet its obligations to policyholders. The Lloyd's New Central Fund is funded by an annual levy imposed on members, which is determined annually by Lloyd's as a percentage of each member's written premiums ( 0.5% with respect to 2015). In addition, the Council of Lloyd's has power to call on members to make an additional contribution to the Lloyd's New Central Fund of up to 3.0% of their underwriting capacity each year should it decide that such additional contributions are necessary. The Company currently estimates that its 2015 obligation to the Lloyd's New Central Fund will be approximately $1.0 million and accrues for this obligation ratably throughout the year on a quarterly basis. Lloyd's also imposes other charges on its members and the syndicates on which they participate, including an annual subscription charge ( 0.5% of written premiums with respect to 2015) and an overseas business charge, levied as a percentage of gross international premiums (defined as business outside the U.K. and the Channel Islands), with the percentage depending on the type of business written. Lloyd's also has power to impose additional charges under Lloyd's Powers of Charging Byelaw. The Company currently estimates that its 2015 obligation to Lloyd's for such charges will be approximately $1.0 million and accrues for this obligation ratably throughout the year on a quarterly basis. Reinsurance commitments . In the ordinary course of business, the Company periodically enters into reinsurance agreements that include terms that could require the Company to collateralize certain of its obligations. Employment agreements. The Company has entered into employment agreements with certain officers that provide for equity incentive awards, executive benefits and severance payments under certain circumstances. Operating leases. The Company leases office space and office equipment under operating leases. Future minimum lease commitments at September 30, 2015 are as follows: Twelve months ended September 30, Amount 2016 $ 17,657 2017 16,415 2018 16,425 2019 15,825 2020 14,795 2021 and thereafter 30,894 $ 112,011 Total net lease expense under operating leases for the nine months ended September 30, 2015 was $10.5 million ( 2014 – $11.6 million ). Legal proceedings. The Company is party to various legal proceedings generally arising in the normal course of its business. While any proceeding contains an element of uncertainty, the Company does not believe that the eventual outcome of any litigation or arbitration proceeding to which it is presently a party could have a material adverse effect on its financial condition or business. Pursuant to the Company's insurance and reinsurance agreements, disputes are generally required to be settled by arbitration.

Acquisition of Montpelier

Acquisition of Montpelier	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	11. Acquisition of Montpelier On March 31, 2015, the Company announced the signing of a definitive agreement and plan of merger (the "Merger Agreement") with Montpelier and Millhill Holdings Ltd., a direct, wholly-owned subsidiary of the Company ("Merger Sub"), under which Endurance Holdings, through Merger Sub, acquired all of the outstanding common shares of Montpelier. The acquisition of Montpelier was completed on July 31, 2015 (the "Closing Date"). Prior to the closing of the acquisition, Montpelier was a publicly traded company listed on the New York Stock Exchange and headquartered in Bermuda. As of the close of trading on July 31, 2015, the common shares of Montpelier ceased trading. The aggregate consideration for the transaction consisted of the issuance of 20.7 million of the Company’s ordinary shares valued at $1.4 billion and $451.1 million of cash. The cash consideration was funded through a pre-closing dividend from Montpelier of $9.89 per common share, or $451.1 million (the "Special Dividend"). In connection with the acquisition of Montpelier, the Company incurred one-time transaction and integration related expenses of $64.0 million in the three months ended September 30, 2015 , which included $14.8 million related to transaction costs, including due diligence, legal, accounting and investment banking fees and expenses, $1.0 million of costs related to the integration of Montpelier and the Company, and $48.2 million of compensation-related costs associated with terminating employees of Montpelier. In the nine months ended September 30, 2015 , the Company incurred $68.5 million of one-time transaction and integration related expenses. These expenses have all been reported as a component of corporate expenses. Purchase price The Company's total purchase price for Montpelier at July 31, 2015 was calculated as follows: Consideration paid by Endurance Number of Montpelier common shares outstanding immediately prior to the closing of the acquisition 43,827,753 Exchange ratio 0.472 Total Company ordinary shares 20,686,699 Company ordinary share closing price on July 31, 2015 $ 69.49 Total value of Company ordinary shares $ 1,437,519 Fair value of restricted share units attributable to service period prior to merger date (1) $ 33,327 Total consideration $ 1,470,846 Special Dividend paid by Montpelier Number of Montpelier common shares and restricted share units eligible for special dividend 45,611,810 Special dividend paid per Montpelier common share and restricted share unit $ 9.89 Total special dividend consideration paid to Montpelier common shareholders $ 451,101 Total consideration received by Montpelier common shareholders $ 1,921,947 Less: Special Dividend paid by Montpelier (451,101 ) Net purchase price $ 1,470,846 (1) Outstanding Montpelier restricted share units were assumed by the Company and adjusted as of the Closing Date to represent the right to receive 0.472 Company ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of Company ordinary shares. The fair value of the Montpelier restricted share units was determined based on the closing price of the Company's ordinary shares on the Closing Date. The resulting fair value of the restricted share units was apportioned as purchase consideration based on service provided to Montpelier as of the Closing Date with the remaining fair value of these restricted share units to be recognized prospectively over the restricted share units' remaining vesting period. 11. Acquisition of Montpelier, cont'd. Fair value of net assets acquired and liabilities assumed The purchase price was allocated to the acquired assets and liabilities of Montpelier based on estimated fair values on July 31, 2015 , the date the transaction closed, as detailed below. The Company recognized goodwill of $87.6 million primarily attributable to Montpelier's assembled workforce and synergies expected to result upon integration of Montpelier into the Company's operations. The Company estimates that none of the goodwill that was recorded will be deductible for income tax purposes. The allocation of the purchase price is based on information that was available to management at the time the consolidated financial statements were prepared. The allocation may change as additional information becomes available within the measurement period, which cannot exceed 12 months from the acquisition date. The fair value recorded for these items may be subject to adjustments, which may impact the individual amounts recorded for assets acquired and liabilities assumed, as well as the residual goodwill. The Company identified finite lived intangible assets of $293.2 million , which will be amortized over a weighted average period of 8 years, identifiable indefinite lived intangible assets of $57.6 million , and certain other adjustments to the fair values of the assets acquired, liabilities assumed and shareholders' equity of Montpelier at September 30, 2015 as summarized in the table below: Montpelier shareholders' equity attributable to controlling interest prior to Special Dividend $ 1,560,255 Cash and cash equivalents (Special Dividend on Montpelier common shares and Montpelier equity awards) (451,101 ) Adjusted shareholders' equity of Montpelier as of July 31, 2015 1,109,154 Adjustments for fair value, by applicable balance sheet caption: Assets: Fixed maturity investments, trading at fair value (11,100 ) Deferred acquisition costs (91,713 ) Reinsurance recoverable on unpaid losses (675 ) Other assets (12,459 ) Liabilities: Reserve for losses and loss expenses 10,822 Debt 21,123 Deferred tax liability (18,346 ) Equity: Non-controlling interest 25,615 Total adjustments for fair value by applicable balance sheet caption (76,733 ) Adjustments for fair value of the identifiable intangible assets: Identifiable indefinite lived intangible assets (insurance licenses, Lloyd's syndicate capacity and asset management agreements) 57,600 Identifiable finite lived intangible assets (non-contractual relationships, Lloyd's syndicate distribution channel, renewal rights, value of business acquired, trademarks and trade names, covenants not to compete and asset management agreements) 293,200 Total adjustments for fair value by applicable balance sheet caption and identifiable intangible assets 274,067 Estimated fair value of net assets acquired and identifiable intangible assets 1,383,221 Total consideration paid by Endurance Holdings 1,470,846 Estimated total consideration over the fair value of net assets acquired assigned to goodwill $ 87,625 11. Acquisition of Montpelier, cont'd. An explanation of the significant fair value adjustments is as follows: • Fixed maturity investments, trading at fair value - To reflect certain investments at fair value; • Deferred acquisition costs - To eliminate Montpelier's deferred acquisition costs; • Other assets - To eliminate deferred debt issuance costs related to Montpelier's existing senior notes and to write off Montpelier's fixed assets and goodwill; • Reserve for losses and loss expenses - To reflect a decrease in net losses and loss expenses due to the addition of a market based risk margin, which represents the cost of capital required by a market participant to assume the net losses and loss expenses of Montpelier, offset by a deduction that represents the discount due to the present value calculation of the unpaid losses and loss expenses based on the expected payout of the net unpaid losses and loss expenses; • Debt - To reflect Montpelier's existing senior notes and trust preferred securities at fair value using indicative market pricing obtained from third-party service providers; • Deferred tax liability - To reflect the deferred tax liability on identifiable intangible assets; and • Identifiable indefinite lived and finite lived intangible assets - To establish the fair value of identifiable intangible assets related to the acquisition of Montpelier described in detail below. Identifiable intangible assets at July 31, 2015 consisted of the following, and are included in goodwill and other intangible assets on the Company's consolidated balance sheets: Amount Economic Useful Life Key non-contractual relationships $ 71,800 10 Other non-contractual relationships 22,400 3 Trade names 1,800 Various Insurance licenses 1,900 Indefinite Non-compete agreements 5,700 Various Lloyd's syndicate capacity 48,300 Indefinite Lloyd's syndicate distribution channel 18,400 10 Renewal rights 82,100 15 Value of business acquired 88,400 2 Asset management agreements 10,000 Various Identifiable intangible assets, before amortization, at July 31, 2015 350,800 Amortization (from July 31, 2015 through September 30, 2015) (9,734 ) Net identifiable intangible assets at September 30, 2015 related to the acquisition of Montpelier $ 341,066 The following table reconciles the carrying amount of goodwill from December 31, 2014 to September 30, 2015: Nine Months Ended September 30, 2015 Balance at December 31, 2014 $ 91,238 Additions 87,625 Foreign currency translation (1,437 ) Balance at September 30, 2015 $ 177,426 11. Acquisition of Montpelier, cont'd. An explanation of the identifiable intangible assets is as follows: • Key non-contractual relationships - these relationships included Montpelier's top brokers and consideration was given to the expectation of the renewal of these relationships and the associated expenses; • Other non-contractual relationships - these relationships consisted of Montpelier's brokers with the exception of those top brokers previously listed above as key non-contractual relationships and consideration was given to the expectation of the renewal of these relationships and the associated expenses; • Trade names - represents the value of the Montpelier and Blue Capital brands acquired; • Insurance licenses - the value of insurance licenses acquired providing the ability to write reinsurance in 15 states of the U.S.; • Non-compete agreements - represent non-compete agreements with key employees of Montpelier; • Lloyd's syndicate capacity - the value of Lloyd's syndicate capacity, which represents Montpelier's authorized premium income limit to write insurance business in the Lloyd's marketplace; • Lloyd's syndicate distribution channel - the value of sales of insurance policies that result directly from relationships between Lloyd's and the brokers in the Lloyd's marketplace; • Renewal rights - the value of policy renewal rights taking into consideration written premium on assumed retention ratios and the insurance cash flows and the associated equity cash flows from these renewal policies over the expected life of the renewals; • Value of business acquired ("VOBA") - the expected future losses and expenses associated with the policies that were in-force as of the closing date of the transaction were estimated and compared to the future premium remaining expected to be earned. The difference between the risk-adjusted future loss and expenses, discounted to present value and the unearned premium reserve, was estimated to be the VOBA; and • Asset management contracts - represents the value of the Blue Capital asset management contracts acquired. Financial results The following table summarizes the results of Montpelier since July 31, 2015 that have been included in the Company's Condensed Consolidated Statement of Income and Comprehensive Income for the three and nine months ended September 30, 2015 and the Company's Condensed Consolidated Balance Sheet as at September 30, 2015 . For the period from July 31, 2015 to September 30, 2015 Total revenues $ 94,249 Net loss attributable to the Company's common shareholders (1) (10,058 ) (1) Includes $48.2 million of compensation-related costs associated with terminating employees of Montpelier. 11. Acquisition of Montpelier, cont'd. Supplemental pro forma information The following table presents unaudited pro forma consolidated financial information for the three and nine months ended September 30, 2015 and 2014 and assumes the acquisition of Montpelier occurred on January 1, 2014. The unaudited pro forma consolidated financial information is provided for informational purposes only and is not necessarily, and should not be assumed to be, an indication of the results that would have been achieved had the transaction been completed as of January 1, 2014 or that may be achieved in the future. The unaudited pro forma consolidated financial information does not give consideration to the impact of possible revenue enhancements, expense efficiencies, synergies or asset dispositions that may result from the acquisition of Montpelier. In addition, unaudited pro forma consolidated financial information does not include the effects of costs associated with any restructuring or integration activities resulting from the acquisition of Montpelier, as they are nonrecurring. Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Total revenues $ 627,394 $ 701,332 $ 1,886,038 $ 2,030,119 Net income available to Endurance Holdings' common shareholders 100,046 86,755 345,086 264,799 Among other adjustments, and in addition to the fair value adjustments and recognition of goodwill and identifiable intangible assets noted above, other material nonrecurring pro forma adjustments directly attributable to the acquisition of Montpelier principally included certain adjustments to recognize transaction related costs, align accounting policies, amortize fair value adjustments, amortize identifiable indefinite lived intangible assets and recognize related tax impacts.

Debt And Financing Arrangements

Debt And Financing Arrangements	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Debt Disclosure [Text Block]	12. Debt and financing arrangements Credit Facility On April 19, 2012, the Company and certain designated subsidiaries of the Company entered into a $700.0 million revolving credit facility with JPMorgan Chase Bank, N.A. ("JPMorgan") as administrative agent ("Credit Facility"). The Credit Facility consists of two tranches: (i) a tranche 1 secured credit facility in an aggregate principal amount of $560.0 million , which is secured on a several basis by the respective entity incurring such obligation by cash and securities deposited into collateral accounts from time to time with Deutsche Bank Trust Company Americas and (ii) a tranche 2 unsecured facility in an aggregate principal amount of $140.0 million . The proceeds of the Credit Facility may be used for general corporate purposes, to finance potential acquisitions and for the repurchase of the Company’s outstanding publicly or privately issued securities. So long as the Company is not in default under the terms of the Credit Facility, the Company may request that the size of the Credit Facility be increased by $350.0 million , provided that no participating lender is obligated to increase its commitments under the Credit Facility. The Credit Facility requires the Company’s compliance with certain customary restrictive covenants. These include certain financial covenants, such as maintaining a leverage ratio (no greater than 0.35 :1.00 at any time) and a consolidated tangible net worth (no less than $1.8 billion at any time). In addition, each of the Company’s regulated insurance subsidiaries that has a claims paying rating from A.M. Best must maintain a rating of at least B++ at all times. The terms of the Credit Facility restrict the declaration or payment of dividends if the Company is already in default or the payment or declaration would cause a default under the terms of the Credit Facility. The Credit Facility also contains customary event of default provisions, including failure to pay principal or interest under the Credit Facility, insolvency of the Company, a change in control of the Company, a breach of the Company’s representations or covenants in the Credit Facility or a default by the Company under its other indebtedness. The Company was in compliance with all covenants contained within the Credit Facility as of September 30, 2015 . As of September 30, 2015 and December 31, 2014 , there were no borrowings under the Credit Facility and letters of credit outstanding under the Credit Facility were $199.6 million and $204.0 million , respectively. The Credit Facility expires on April 19, 2016. 12. Debt and financing arrangements, cont'd. BCRH Credit Agreement Upon closing of the acquisition of Montpelier on July 31, 2015, the Company became a guarantor of the BCRH 364 -day unsecured credit agreement (the "BCRH Credit Agreement"), which permits BCRH to borrow up to $20.0 million on a revolving basis for working capital and general corporate purposes. The Company is entitled to receive an annual guarantee fee from BCRH equal to 0.125% of the facility's total capacity. See Note 13, Related party transactions. As of September 30, 2015 , BCRH had $9.0 million outstanding borrowings under the BCRH Credit Agreement. With respect to BCRH's outstanding borrowings at September 30, 2015 , $4.0 million must be repaid or extended, in the form of a new borrowing, no later than November 2, 2015 and is subject to an annual interest rate of 1.41% , and $5.0 million must be repaid or extended, in the form of a new borrowing, no later than December 21, 2015 and is subject to an annual interest rate of 1.45% . The BCRH Credit Agreement contains covenants that limit BCRH’s ability to, among other things, grant liens on its assets, sell assets, merge or consolidate, incur debt and enter into certain transactions with affiliates. The BCRH Credit Agreement also contains covenants that require BCRH to maintain a debt to total capitalization ratio less than or equal to 22.5% and to maintain at least 70% of its total shareholders’ equity as of the date of the BCRH Credit Agreement. In addition, an uncured default by the Company of the covenants contained in the Credit Facility would result in a default under the BCRH Credit Agreement. If BCRH or the Company were to fail to comply with any of the applicable covenants, the lender could revoke the facility and exercise remedies against BCRH or the Company. The Company was in compliance with all covenants applicable to the Company in the BCRH Credit Agreement as of September 30, 2015 . BCGR Credit Agreement Upon closing of the acquisition of Montpelier on July 31, 2015, the Company became a guarantor of the BCGR 364 -day unsecured credit agreement (the "BCGR Credit Agreement"), which permits the BCGR Listed Fund to borrow up to $20.0 million on a revolving basis for working capital and general corporate purposes. The Company is entitled to receive an annual guarantee fee from the BCGR Listed Fund equal to 0.125% of the facility's total capacity. See Note 13, Related party transactions. As of September 30, 2015 , the BCGR Listed Fund had $6.0 million of outstanding borrowings under the BCGR Credit Agreement. With respect to BCGR's outstanding borrowings at September 30, 2015 , $3.0 million must be repaid or extended, in the form of a new borrowing, no later than February 1, 2016 and is subject to an annual interest rate of 1.54% , and $3.0 million must be repaid or extended, in the form of a new borrowing, no later than February 12, 2016 and is subject to an annual interest rate of 1.51% . The BCGR Credit Agreement contains covenants that limit the BCGR Listed Fund's ability, among other things, to grant liens on its assets, sell assets, merge or consolidate, incur debt and enter into certain transactions with affiliates. In addition, an uncured default by the Company of the covenants contained in the Credit Facility would result in a default under the BCGR Credit Agreement. If the BCGR Listed Fund or the Company were to fail to comply with any of the applicable covenants, the lender could revoke the facility and exercise remedies against the BCGR Listed Fund or the Company. The Company was in compliance with all covenants applicable to the Company in the BCGR Credit Agreement as of September 30, 2015 . Uncommitted Letter of Credit Agreements The Company is party to certain uncommitted letter of credit reimbursement agreements ("LOC Agreements") that allow for the issuance of letters of credit in a variety of currencies, including U.S. dollars. The fees paid under the LOC Agreements depend on the amount of the outstanding letters of credit and vary from 0.30% to 0.45% on the principal amount of letters of credit outstanding to a fee negotiated at the time of issuance of the individual letters of credit. The total amount of letters of credit outstanding under the LOC Agreements as of September 30, 2015 was $27.6 million ( December 31, 2014 - $5.9 million ). 12. Debt and financing arrangements, cont'd. 7% Senior Notes The Company has issued $335.0 million principal amount of 7% Senior Notes due July 15, 2034 (the "7% Senior Notes"). The 7% Senior Notes are senior unsecured obligations of Endurance Holdings and rank equally with all of Endurance Holdings’ existing and future unsecured and unsubordinated debt. The 7% Senior Notes are also effectively junior to claims of creditors of Endurance Holdings’ subsidiaries, including policyholders, trade creditors, debt holders, and taxing authorities. The indentures governing the 7% Senior Notes contain customary covenants and events of default for senior unsecured indebtedness, including events of default for non-payment of principal or interest, breaches of covenants, insolvency of the Company or a default by the Company under other outstanding indebtedness. The Company was in compliance with all covenants contained within the indentures governing the 7% Senior Notes as of September 30, 2015 . 6.15% Senior Notes The Company issued $200.0 million principal amount of 6.15% Senior Notes due October 15, 2015 (the "6.15% Senior Notes"). The 6.15% Senior Notes were senior unsecured obligations of Endurance Holdings and ranked equally with all of Endurance Holdings’ existing and future unsecured and unsubordinated debt. The 6.15% Senior Notes also were effectively junior to claims of creditors of Endurance Holdings’ subsidiaries, including policyholders, trade creditors, debt holders, and taxing authorities. The indentures governing the 6.15% Senior Notes contain customary covenants and events of default for senior unsecured indebtedness, including events of default for non-payment of principal or interest, breaches of covenants, insolvency of the Company or a default by the Company under other outstanding indebtedness. The Company was in compliance with all covenants contained within the indentures governing the 6.15% Senior Notes as of September 30, 2015 . The 6.15% Senior Notes matured on October 15, 2015 and were retired by the Company on that date. 4.7% Senior Notes Upon closing of the acquisition of Montpelier, Montpelier, as issuer, Endurance Holdings, as parent guarantor, and The Bank of New York Mellon, as trustee, entered into a Fourth Supplemental Indenture, dated as of July 31, 2015 (the "Fourth Supplemental Indenture"). The Fourth Supplemental Indenture amended the Indenture, dated as of July 15, 2003 (as amended and supplemented from time to time (collectively, the "Senior Notes Supplemental Indentures")). The Senior Notes Supplemental Indentures provided for the unconditional assumption of the due and punctual payment of the principal of, any premium and interest on and any additional amounts with respect to the 4.7% Senior Unsecured Notes Due 2022 (the "4.7% Senior Notes") and the performance of every obligation in the Senior Notes Indenture and the Outstanding 4.7% Senior Notes to be performed or observed. Montpelier originally issued the 4.7% Senior Notes on October 2, 2012 in an aggregate principal amount of $300.0 million . The 4.7% Senior Notes bear a rate of interest equal to 4.7% per annum, payable semi-annually in arrears on April 15 and October 15 each year. The 4.7% Senior Notes mature on October 15, 2022. The 4.7% Senior Notes do not contain any covenants regarding financial ratios or specified levels of net worth or liquidity to which the Company or any of its subsidiaries must adhere. Trust Preferred Securities Subsequent to the acquisition of Montpelier, Montpelier, as issuer, Endurance Holdings, as parent guarantor, and Wilmington Trust Company, as trustee, entered into the Second Supplemental Indenture, dated as of July 31, 2015 (the "Second Supplemental Indenture"). The Second Supplemental Indenture amended the Junior Subordinated Indenture, dated as of January 6, 2006 (as amended and supplemented from time to time (collectively, the "Junior Subordinated Supplemental Indentures")). The Junior Subordinated Supplemental Indentures provided for the express assumption by Endurance Holdings of the due and punctual payment of the principal of and any premium and interest (including any additional interest) on all of the Trust Preferred Securities and the performance of every covenant of the Junior Subordinated Indenture on the part of Montpelier to be performed or observed. Montpelier originally issued the Trust Preferred Securities in January 2006 in an aggregate principal amount of $100.0 million . The Trust Preferred Securities mature on March 30, 2036 and bear interest at a floating rate of 3-month LIBOR plus 380 basis points, reset quarterly. The Trust Preferred Securities may be redeemed at the option of the issuer prior to maturity at a redemption price 12. Debt and financing arrangements, cont'd. equal to 100% of the principal amount thereof plus accrued interest, provided that the issuer has received the prior approval of any applicable insurance regulatory authority with respect to such redemption, if required. The Trust Preferred Securities do not contain any covenants regarding financial ratios or specified levels of net worth or liquidity to which the Company or any of its subsidiaries must adhere. LIBOR Swap Upon closing of the acquisition of Montpelier, the Company became a party to the LIBOR Swap, which will result in the future net cash flows in connection with the Trust Preferred Securities for the 5 -year period beginning March 30, 2012 being the same as if these securities bore interest at a fixed rate of 4.905% , provided the Company holds the LIBOR Swap to its maturity. Net realized and unrealized gains and losses associated with the LIBOR Swap are reported within net realized and unrealized gains on the Company's Condensed Consolidated Statements of Income and Comprehensive Income, as opposed to interest expense.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2015
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	13. Related party transactions BlackRock Since 2002, subsidiaries of BlackRock Inc. ("BlackRock") have provided the Company and certain of its subsidiaries with various investment management, investment accounting and risk analysis services. BlackRock owned approximately 3.9 million or 5.8% of Endurance Holdings' ordinary shares outstanding at September 30, 2015 and were therefore considered a related party. The Company incurred expenses totaling $0.8 million and $2.5 million ( 2014 : $0.8 million and $2.3 million ) for the three and nine months ended September 30, 2015 in relation to investment services rendered by BlackRock, of which $1.1 million was accrued at September 30, 2015 (December 31, 2014 : $1.5 million ). BCRH BCRH provides fully-collateralized property catastrophe reinsurance and invests in various insurance-linked securities through its subsidiaries Blue Capital Re and Blue Capital Re ILS. As of September 30, 2015 the Company owned 33.3% of BCRH's outstanding common shares. The underwriting decisions and operations of BCRH and its subsidiaries are managed by BCML, and each uses the Company's reinsurance underwriting expertise and infrastructure to conduct its business. In addition, Blue Water Re, the Company's wholly-owned special purpose insurance company, is a significant source of reinsurance business for BCRH. Officers of the Company serve as a Chairman of the Board, Chief Executive Officer and Chief Financial Officer of BCRH. The Company provides services to BCRH and its subsidiaries through the following arrangements: BW Retrocessional Agreement. Through a retrocessional contract dated December 31, 2013 (the "BW Retrocessional Contract"), between Blue Capital Re and Blue Water Re, Blue Water Re has the option to cede to Blue Capital Re up to 100% of its participation in the ceded reinsurance business it writes, provided that such business is in accordance with Blue Capital Re's underwriting guidelines. Pursuant to the BW Retrocessional Contract, Blue Capital Re may participate in: (i) retrocessional, quota share or other agreements between Blue Water Re and Montpelier Re or other third-party reinsurers, which provides it with the opportunity to participate in a diversified portfolio of risks on a proportional basis; and (ii) fronting agreements between Blue Water Re and Montpelier Re or other well capitalized third party rated reinsurers, which allows Blue Capital Re to transact business with counterparties who prefer to enter into contracts with rated reinsurers. Investment Management Agreement. On November 12, 2013, BCRH entered into an Investment Management Agreement with BCML (the "Investment Management Agreement"). Pursuant to the terms of the Investment Management Agreement, BCML has full discretionary authority, including the delegation of the provision of its services, to manage BCRH's assets, subject to its underwriting guidelines, the terms of the Investment Management Agreement and the oversight of BCRH's board of directors. 13. Related party transactions, cont'd. Underwriting and Insurance Management Agreement. BCRH, Blue Capital Re and BCML have entered into an Underwriting and Insurance Management Agreement (the "Underwriting and Insurance Management Agreement"). Pursuant to the Underwriting and Insurance Management Agreement, BCML provides underwriting, risk management, claims management, ceded retrocession agreements management, and actuarial and reinsurance accounting services to Blue Capital Re. BCML has full discretionary authority to manage the underwriting decisions of Blue Capital Re, subject to BCRH's underwriting guidelines, the terms of the Underwriting and Insurance Management Agreement and the oversight of BCRH's and Blue Capital Re's boards of directors. Administrative Services Agreement. BCRH has entered into an Administrative Services Agreement with BCML, as amended on November 13, 2014 (the "Administrative Services Agreement"). Pursuant to the terms of the Administrative Services Agreement, BCML provides BCRH with support services, including but not limited to finance and accounting, internal audit, claims management, legal, modeling , office space, information technology, human resources and administrative support. BCRH and its subsidiaries may not terminate the Investment Management Agreement, the Underwriting and Insurance Management Agreement or the Administrative Services Agreement until the fifth anniversary of the completion of the BCRH initial public offering, whether or not BCML's performance is satisfactory. Upon any termination or non-renewal of either of the Investment Management Agreement or the Underwriting and Insurance Management Agreement (other than for a material breach by, or the insolvency of, BCML), BCRH and/or its subsidiaries must pay a one-time termination fee to BCML equal to 5% of its U.S. GAAP shareholders' equity, calculated as of the most recently completed quarter prior to the date of termination (approximately $9.1 million as of September 30, 2015 ). BCRH Credit Agreement. The Company serves as a guarantor for the BCRH Credit Agreement and is entitled to an annual fee equal to 0.125% of the facility's total capacity. See Note 12, Debt and financing arrangements. BCGR Credit Agreement. The Company serves as a guarantor for the BCGR Credit Agreement and is entitled to an annual fee equal to 0.125% of the facility's total capacity. See Note 12, Debt and financing arrangements. On a stand-alone basis, any fees incurred pursuant to the Investment Management Agreement, the Underwriting and Insurance Management Agreement or the Administrative Services Agreement, including any fees triggered upon termination or non-renewal of any of them, represent expenses to BCRH and /or its subsidiaries and revenues to BCML. On a consolidated basis, the portion of such fees incurred by BCRH's non-controlling interests pursuant to these agreements represent a decrease to the net income attributable to non-controlling interests on the Company's Consolidated Statement of Income and Comprehensive Income, thereby increasing the net income and comprehensive income available to the Company. During the three and nine month periods ended September 30, 2015 , the Company earned the following fees from BCRH: (i) $0.4 million and $0.4 million , respectively, pursuant to the Investment Management Agreement; (ii) $0.1 million and $0.1 million , respectively, pursuant to the Administrative Services Agreement; and (iii) $0.1 million and $0.1 million , respectively, pursuant to the Underwriting and Insurance Management Agreement. During the three and nine months ended September 30, 2015 , the Company earned less than $0.1 million as a guarantor for the BCRH Credit Agreement and BCGR Credit Agreement. As of September 30, 2015 , BCRH and its subsidiaries owed the Company $2.0 million for the services performed pursuant to the aforementioned agreements.

Summary Of Significant Accoun21

Summary Of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Investments	(a) Investments The Company classifies its fixed maturity investments, short-term investments and equity securities as trading or available for sale. Trading securities are carried at estimated fair value, with related net realized and unrealized gains or losses included in earnings. The Company has elected to account for trading securities using the fair value option under current accounting guidance, as the Company believes it represents the most meaningful measurement basis for these assets and liabilities. Available for sale securities are carried at estimated fair value, with related net unrealized gains or losses excluded from earnings and included in shareholders' equity as a component of accumulated other comprehensive (loss) income. Investment transactions are recorded on a trade date basis. The Company determines the fair value of its trading and available for sale investments in accordance with current accounting guidance, which defines fair value and establishes a fair value hierarchy based on inputs to the various valuation techniques used for each fair value measurement. The use of valuation techniques for any given investment requires a significant amount of judgment and consideration of factors specific to the underlying investment. Fair value measurements determined by the Company seek to maximize observable 2. Summary of significant accounting policies, cont'd. (a) Investments, cont'd. inputs and minimize the use of unobservable inputs. Current accounting guidance establishes three levels as follows: Level 1: Unadjusted quoted prices in active markets for identical assets or liabilities. Level 2: Quoted prices for similar assets in markets that are active, quoted prices for identical or similar assets in markets that are not active or inputs that are observable either directly or indirectly. Level 2 inputs include quoted prices for similar assets or liabilities other than quoted prices in Level 1; quoted prices in markets that are not active; or other inputs that are observable or can be derived principally from or corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3: Unobservable inputs that are supported by little or no market activity and are significant to the fair value of the assets or liabilities. Unobservable inputs reflect the Company’s own views about the assumptions that market participants would use in pricing the asset or liability. Level 3 assets and liabilities include financial instruments whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. The Company determines the estimated fair value of each individual security utilizing the highest level inputs available. Transfers between levels are assumed to occur at the end of each period. If the Company has the intent to sell a fixed maturity or short-term security classified as available for sale in an unrealized loss position or it is more likely than not that the Company will be required to sell the available for sale security, the Company deems the security to be other-than-temporarily impaired and writes down the carrying value of the security to fair value, thereby establishing a new cost basis. The amount of the write-down is recognized in earnings as an other-than-temporary impairment ("OTTI") loss. For fixed maturity and short-term investments classified as available for sale in an unrealized loss position for which a decision to sell has not been made and it is not more likely than not that the Company will be required to sell the security, the Company performs additional reviews to determine whether the investment will recover its amortized cost. If the amortized cost of the Company's fixed maturity and short-term investments classified as available for sale is, based on the judgment of management, unlikely to be recovered, the Company writes down the investment by the amount representing the credit related portion of the decline in value, thereby establishing a new cost basis. The amount of the write-down is recognized in earnings as an OTTI loss. The new cost basis is not changed for subsequent recoveries in fair value. To the extent the Company determines that the amortized cost of the Company’s fixed maturity and short-term investments classified as available for sale is likely to be recovered and the decline in value is related to non-credit factors (such as interest rates, market conditions, etc.) and not due to credit related factors, that remaining non-credit portion of the unrealized loss is recorded as a part of accumulated other comprehensive (loss) income in the shareholders' equity section of the Company's Unaudited Condensed Consolidated Balance Sheets. For equity securities classified as available for sale, the Company considers its ability and intent to hold the equity security in an unrealized loss position for a reasonable period of time to allow for a full recovery. When the Company determines that the decline in value of an equity security classified as available for sale is other-than-temporary, the Company reduces the cost of the equity security to its fair value and recognizes the loss in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income. The new cost basis is not changed for subsequent recoveries in fair value. 2. Summary of significant accounting policies, cont'd. (a) Investments, cont'd. Other investments within the Company's investment portfolio are comprised of (i) hedge funds, private investment funds and other investment funds that generally invest in senior secured bank debt, high yield credit securities, distressed debt, macro strategies, multi-strategy, equity long/short strategies, distressed real estate, and energy sector private equity ("alternative funds") and (ii) high yield loan funds ("specialty funds"). Other investments are accounted for using the equity method of accounting whereby the initial investment is recorded at cost. The carrying values of these investments are increased or decreased to reflect the Company's share of income or loss, which is included in net investment income, and are decreased for dividends. Due to the timing of the delivery of the final valuations reported by the managers of certain of our alternative and specialty funds, our investments in those funds are estimated based on the most recently available information including period end valuation statements, period end estimates, or, in some cases, prior month or quarter valuation statements.
Non-controlling Interests	(b) Non-controlling interests The Company accounts for non-controlling interests in the shareholders' equity section of the Company's Unaudited Condensed Consolidated Balance Sheets in accordance with current accounting guidance regarding consolidation, and presents such non-controlling shareholders' interest in the net assets of the subsidiary. Net income attributable to non-controlling interest is presented separately in the Company's Unaudited Condensed Consolidated Statements of Income and Comprehensive Income.
New Accounting Pronouncements	(c) Recent accounting pronouncements In February 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-02, "Amendments to the Consolidation Analysis". Under ASU 2015-02, all legal entities are required to evaluate whether they should consolidate certain legal entities. ASU 2015-02 set forth amendments: (1) modifying the evaluation of whether limited partnerships and similar legal entities are variable interest entities ("VIEs") or voting interest entities; (2) eliminating the presumption that a general partner should consolidate a limited partnership; (3) affecting the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships; and (4) providing a scope exception from consolidation guidance for certain reporting entities. ASU 2015-02 is effective for public business entities for annual and interim periods beginning after December 15, 2015. Early adoption is permitted. ASU 2015-02 may be applied retrospectively or by using a modified retrospective approach by recording a cumulative-effect adjustment to equity as of the beginning of the year of adoption. The Company is currently evaluating the impact of this guidance. In April 2015, the FASB issued ASU 2015-03, "Simplifying the Presentation of Debt Issuance Costs" ("ASU 2015-03"). The objective of ASU 2015-03 is to simplify the presentation of debt issuance costs by requiring direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in ASU 2015-03. ASU 2015-03 is effective for public business entities in annual and interim periods beginning after December 15, 2015. Early adoption is permitted. ASU 2015-03 should be applied retrospectively, and upon transition, applicable disclosures for a change in accounting principle shall be provided, including the transition method, a description of the prior period information that has been retroactively adjusted, and the effect of the change on the applicable financial statement line items. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements. In May 2015, the FASB issued ASU 2015-07, "Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent)" ("ASU 2015-07"). The objective of ASU 2015-07 is to remove the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using net asset value per share. ASU 2015-07 is effective for public business entities in annual and interim periods beginning after December 15, 2015. Early adoption is permitted. ASU 2015-07 should be applied retrospectively. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements. 2. Summary of significant accounting policies, cont'd. (c) Recent accounting pronouncements, cont'd. In May 2015, the FASB issued ASU 2015-09, "Disclosures about Short-Duration Contracts" ("ASU 2015-09"). The objective of ASU 2015-09 is to make targeted improvements to disclosure requirements for insurance companies that issue short-duration contracts. The guidance requires additional disclosures of claims development tables, frequency of reported claims, and history of claims duration. This information is required to be disaggregated so that useful information is not obscured by either the inclusion of a large amount of insignificant detail, or the aggregation of items that have significantly different characteristics. ASU 2015-09 is effective for public business entities in annual periods beginning after December 15, 2015, and interim periods within annual periods beginning after December 15, 2016. Early adoption is permitted. ASU 2015-09 should be applied retrospectively. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company's Unaudited Condensed Consolidated Financial Statements. In September 2015, the FASB issued ASU 2015-16, "Simplifying the Accounting for Measurement-Period Adjustments" ("ASU 2015-16"). ASU 2015-16 eliminates the requirement that an acquirer in a business combination account for measurement-period adjustments retrospectively. Instead, an acquirer will recognize a measurement-period adjustment during the period in which it determines the amount of the adjustment. ASU 2015-16 is effective for public business entities in annual periods beginning after December 15, 2015, and interim periods within annual periods beginning after December 15, 2015. Early adoption is permitted. The Company is currently evaluating the impact of this guidance.

Investments (Policy)

Investments (Policy)	9 Months Ended
	Sep. 30, 2015
Investments [Abstract]
Other Investments	In addition to the Company's fixed maturity, short-term and equity investments, the Company invests in alternative funds and specialty funds. The Company's alternative funds and specialty funds are recorded on the Company's balance sheet as "other investments.
Gain Loss On Investments	Realized and unrealized gains and losses are recognized in earnings using the first in, first out method.
Variable Interest Entities	Other Investments The Company is involved in the normal course of business with variable interest entities ("VIEs") as a passive investor in residential and commercial mortgage-backed securities and through its interests in various other investments that are structured as limited partnerships considered to be third party VIEs. The Company determines whether it is the primary beneficiary of an entity subject to consolidation based on a qualitative assessment of the VIE's capital structure, contractual terms, nature of the VIE's operations and purpose and the Company's relative exposure to the related risks of the VIE on the date it becomes initially involved in the VIE. The Company reassesses its VIE determination with respect to an entity on an ongoing basis. The Company determined that it was not the primary beneficiary for any of these investments as of September 30, 2015 . The Company believes its exposure to loss with respect to these investments is generally limited to the investment carrying amounts reported in the Company's Unaudited Condensed Consolidated Balance Sheets and any unfunded investment commitments. Collateralized Reinsurance Entities As of September 30, 2015, the Company owned 33.3% of the BCRH's common shares. BCRH is considered a VIE under U.S. generally accepted accounting principles ("U.S. GAAP") and the Company has determined that it is BCRH's primary beneficiary. As a result, the Company fully consolidates the assets, liabilities and operations of BCRH and its subsidiaries within its Unaudited Condensed Consolidated Financial Statements. The interests in BCRH and its subsidiaries that the Company fully consolidates that are attributable to third-party investors are reported within the Company's Unaudited Condensed Consolidated Financial Statements as non-controlling interests. The Company reassesses its VIE determination with respect to BCRH on an ongoing basis. As of September 30, 2015, the Company owned 25.1% of the BCGR Listed Fund's ordinary shares. The BCGR Listed Fund is considered a "voting interest entity" under U.S. GAAP and, because the Company owns less than 50% of its outstanding ordinary shares, the Company does not consolidate the BCGR Listed Fund's assets, liabilities or operations within its consolidated financial statements. However, the BCGR Cell and Blue Water Re Ltd. ("Blue Water Re"), the Company's wholly-owned Bermuda-based special purpose insurance vehicle, are considered VIEs under U.S. GAAP and the Company has determined that it is the primary beneficiary of these entities. Therefore, as funds held in the BCGR Listed Fund are deployed into the BCGR Cell, and ultimately into Blue Water Re, they are included in the Company's consolidated financial statements. Conversely, as funds previously deployed by the BCGR Listed Fund and the BCGR Cell into Blue Water Re are returned to the BCGR Listed Fund, they are no longer included in the Company's consolidated financial statements. The interests in the BCGR Cell and Blue Water Re that the Company fully consolidates which are attributable to third-party investors are reported within the Company's consolidated financial statements as non-controlling interests. The Company reassesses its VIE determinations with respect to the BCGR Cell and Blue Water Re on an ongoing basis.

Fair Value Measurement (Policy)

Fair Value Measurement (Policy)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Of Financial Instruments	The Company determines the fair value of the fixed maturity investments, short-term investments, equity securities, other investments, debt, and other assets and liabilities in accordance with current accounting guidance, which defines fair value and establishes a fair value hierarchy based on inputs to the various valuation techniques used for each fair value measurement. The Company determines the estimated fair value of each individual security utilizing the highest level inputs available. Valuation inputs by security type may include the following: • Government and agencies fixed maturity securities – These securities are generally priced by pricing services or index providers. The pricing services or index providers may use current market trades for securities with similar quality, maturity and coupon. If no such trades are available, the pricing service typically uses analytical models which may incorporate option adjusted spreads, daily interest rate data and market/sector news. The Company generally classifies the fair values of government and agencies securities in Level 2. Current issue U.S. government securities are generally valued based on Level 1 inputs, which use the market approach valuation technique. • Government guaranteed corporate fixed maturity securities – These securities are generally priced by pricing services or index providers. The pricing service or index providers may use current market trades for securities with similar quality, maturity and coupon. If no such trades are available, the pricing service typically uses analytical spread models which may incorporate inputs from the U.S. treasury curve or LIBOR. The Company generally classifies the fair values of its government guaranteed corporate securities in Level 2. • Corporate fixed maturity securities – These securities are generally priced by pricing services or index providers. The pricing services or index providers typically use discounted cash flow models that incorporate benchmark curves for treasury, swap and high issuance credits. Credit spreads are developed from current market observations for like or similar securities. The Company generally classifies the fair values of its corporate securities in Level 2. • Equity securities – These securities are generally priced by pricing services or index providers. Depending on the type of underlying equity security or equity fund, the securities are priced by pricing services or index providers based on quoted market prices in active markets or through a discounted cash flow model that incorporates benchmark curves for treasury, swap and credits for like or similar securities. The Company generally classifies the fair values of its equity securities in Level 1 or 2. 4. Fair value measurement, cont'd. • Other assets and liabilities – A portion of other assets and liabilities are composed of a variety of derivative instruments used to enhance the efficiency of the investment portfolio and economically hedge certain risks. These instruments are generally priced by pricing services, broker/dealers and/or recent trading activity. The market value approach valuation technique is used to estimate the fair value for these derivatives based on significant observable market inputs. Certain derivative instruments are priced by pricing services based on quoted market prices in active markets. These derivative instruments are generally classified in Level 1. Other derivative instruments are priced using industry valuation models and are considered Level 2, as the inputs to the valuation model are based on observable market inputs. Also included in this line item are proprietary, non-exchange traded derivative-based risk management products primarily used to address weather and energy risks. The trading market for these weather derivatives are generally linked to energy and agriculture commodities, weather and other natural phenomena. In instances where market prices are not available, the Company uses industry or internally developed valuation techniques such as spread option, Black Scholes, quanto and simulation modeling to determine fair value and classifies these in Level 3. These models may reference prices for similar instruments. • Structured securities including agency and non-agency, residential and commercial, mortgage and asset-backed securities and collateralized loan and debt obligations – These securities are generally priced by broker/dealers. Broker/dealers may use current market trades for securities with similar qualities. If no such trades are available, inputs such as bid and offer, prepayment speeds, the U.S. treasury curve, swap curve and cash settlement may be used in a discounted cash flow model to determine the fair value of a security. The Company generally classifies the fair values of its structured securities in Level 2. • Other investments – Other investments are comprised of alternative funds and specialty funds and are generally priced on net asset values ("NAV") received from the fund managers or administrators. Due to the timing of the delivery of the final NAV by certain of the fund managers, valuations of certain alternative funds and specialty funds are estimated based on the most recently available information, including period end NAVs, period end estimates, or, in some cases, prior month or prior quarter NAVs. As this valuation technique incorporates both observable and significant unobservable inputs, the Company generally classifies the fair value of its other investments in Level 3. • Debt – Outstanding debt consists of the Company's 6.15% Senior Notes due October 15, 2015 (which were repaid by the Company upon maturity), the 7.0% Senior Notes due July 15, 2034, the 4.7% Senior Notes due October 15, 2022 (the "Senior Notes") and the Trust Preferred Securities. The fair values of these securities were obtained from a third party pricing service and pricing was based on the spread above the risk-free yield curve. These spreads are generally obtained from the new issue market, secondary trading and broker-dealer quotes. As these spreads and the yields for the risk-free yield curve are observable market inputs, the fair values of the Senior Notes and the Trust Preferred Securities are classified in Level 2. The carrying values of cash and cash equivalents, accrued investment income, net receivable on sales of investments, net payable on purchases of investments, the amount outstanding under the BCRH Credit Agreement and other financial instruments not described above approximated their fair values at September 30, 2015 and December 31, 2014 .
Fair Value Transfer Between Levels	Transfers between levels are assumed to occur at the end of each period.

Earnings Per Share (Policy)

Earnings Per Share (Policy)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Earnings Per Share	The two-class method utilized by the Company is an earnings allocation formula that determines earnings per share for the holders of Endurance Holdings' ordinary shares (also referred to as "common shares") and participating common shares, which includes unvested restricted shares and restricted share units that receive cash dividends, according to dividends declared and participation rights in undistributed earnings. Net income available to Endurance Holdings common and participating common shareholders is reduced by the amount of dividends declared in the current period and by the contractual amount of dividends that must be paid for the current period related to the Company's common and participating common shares. Any remaining undistributed earnings are allocated to the common and participating common shareholders to the extent that each security may share in earnings as if all of the earnings for the period had been distributed. In periods of loss, no losses are allocated to participating common shareholders. Instead, all such losses are allocated solely to the common shareholders. Basic earnings per Endurance Holdings common share are calculated by dividing net income available to common shareholders by the weighted average number of common shares outstanding. The weighted average number of common shares excludes any dilutive effect of outstanding options and convertible securities such as unvested restricted shares and restricted share units. Diluted earnings per Endurance Holdings common share are based on the weighted average number of common shares and assumes the exercise of all dilutive stock options and the vesting or conversion of all convertible securities such as unvested restricted shares and restricted share units using the two-class method described above.

Derivatives (Policy)

Derivatives (Policy)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Accounting policy for derivatives	The Company regularly transacts in certain derivative-based weather risk management products primarily to address weather and energy risks on behalf of third parties. The markets for these derivatives are generally linked to energy and agriculture commodities, weather and other natural phenomena. Generally, the Company's current portfolio of such derivative contracts is of short duration and such contracts are predominantly seasonal in nature. The Company also invests a portion of its investments with third party investment managers with investment guidelines that permit the use of derivative instruments. The Company may enter derivative transactions directly or as part of strategies employed by its external investment managers. The Company's derivative instruments are recorded in the Condensed Consolidated Balance Sheets at fair value, with changes in fair value and gains and losses recognized in net realized and unrealized gains, net foreign exchange losses and other underwriting income (loss) in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income. The Company's derivatives are not designated as hedges under current accounting guidance. The Company's objectives for holding these derivatives are as follows: Interest Rate Futures, Swaps, Swaptions and Options - to manage exposure to interest rate risk, which can include increasing or decreasing its exposure to this risk through modification of the portfolio composition and duration. Industry Loss Warranty ("ILW") Swaps - to manage underwriting risk. The Company has entered into ILW swap contracts which provide reinsurance-like protection to the Company for specific loss events associated with certain lines of its business. The Company has also sold ILW protection, which provides reinsurance-like protection to third parties for specific loss events. Foreign Exchange Forwards, Futures and Options - as part of overall currency risk management and investment strategies. Credit Default Swaps - to manage market exposures. The Company may assume or economically hedge credit risk through credit default swaps to replicate or hedge investment positions. The original term of these credit default swaps is generally five years or less. To-Be-Announced Mortgage-backed Securities ("TBAs") - to enhance investment performance and as part of overall investment strategy. TBAs represent commitments to purchase or sell a future issuance of agency mortgage-backed securities. For the period between purchase of a TBA and issuance of the underlying securities, the Company’s position is accounted for as a derivative. Energy and Weather Contracts – to address weather and energy risks. The Company may purchase or sell contracts with financial settlements based on the performance of an index linked to a quantifiable weather element, such as temperature, precipitation, snowfall or windspeed, and structures with multiple risk triggers indexed to a quantifiable weather element and a weather sensitive commodity price, such as temperature and electrical power or natural gas. Generally, the Company’s current portfolio of energy and weather derivative contracts is of comparably short duration and such contracts are predominantly seasonal in nature. LIBOR Swap – to establish future net cash flows in connection with the Trust Preferred Securities for the five -year period beginning March 30, 2012 as if these securities bore interest at a fixed rate of 4.905% . See Note 12, Debt and financing arrangements.
Offsetting of derivatives policy	At September 30, 2015 and December 31, 2014 , the Company's other derivative instruments were recorded on a gross basis in the Unaudited Condensed Consolidated Balance Sheets.

Stock-Based Employee Compensa26

Stock-Based Employee Compensation And Other Stock Plans (Policies)	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	The Company uses the Black-Scholes-Merton formula to estimate the value of stock options granted. The fair value of the restricted share units granted or assumed is equal to the fair market value of the Company's ordinary shares on the grant or assumption date, as applicable. Compensation equal to the fair market value of the restricted share units at the measurement date is amortized and charged to income over the vesting period. The fair value of the performance-based restricted shares is measured at the grant date using a Monte Carlo simulation based on pre-established targets relating to certain performance based measures achieved by the Company, with the associated expense recognized over the applicable performance and vesting period. The fair value of the restricted shares granted is equal to the fair market value of the Company's ordinary shares on the grant date. Compensation equal to the fair market value of the restricted shares at the measurement date is amortized and charged to income over the vesting period.

Segment Reporting (Policy)

Segment Reporting (Policy)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment Reporting	The determination of the Company's business segments is based on how the Company monitors the performance of its underwriting operations. The Company has two reportable business segments, Insurance and Reinsurance, which are comprised of the following lines of business: Insurance segment lines of business • Agriculture • Casualty and other specialty • Professional lines • Property, marine and energy Reinsurance segment lines of business • Catastrophe • Property • Casualty • Professional lines • Specialty Management measures Insurance and Reinsurance segment results on the basis of the combined ratio, which is obtained by dividing the sum of the net losses and loss expenses, acquisition expenses and general and administrative expenses by net premiums earned. When purchased within a single line of business, ceded reinsurance and recoveries are accounted for within that line of business. When purchased across multiple lines of business, ceded reinsurance and recoveries are allocated to the lines of business in proportion to the related risks assumed. The Company does not manage its assets by segment; accordingly, investment income and total assets are not allocated to the individual business segments. General and administrative expenses incurred by the segments are allocated directly. Remaining general and administrative expenses not incurred by the segments are classified as corporate expenses and are not allocated to the individual business segments. Ceded reinsurance and recoveries are recorded within the business segment to which they apply. The underwriting results of Montpelier are included in the Company's segment results from August 1, 2015.

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2015
Investments [Abstract]
Composition Of Net Investment Income	The components of net investment income for the three and nine months ended September 30, 2015 and 2014 are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Fixed income investments $ 36,204 $ 28,944 $ 96,145 $ 88,616 Equity investments 1,748 1,015 5,200 3,289 Other investments (17,716 ) (1,785 ) (1,758 ) 22,542 Cash and cash equivalents 515 581 2,108 1,878 20,751 28,755 $ 101,695 $ 116,325 Investment expenses (4,218 ) (3,398 ) (11,049 ) (10,676 ) Net investment income $ 16,533 $ 25,357 $ 90,646 $ 105,649
Contractual Maturities Of Fixed Maturity And Short-Term Investments	Contractual maturities of the Company's fixed maturity and short-term investments are shown below as of September 30, 2015 and December 31, 2014 . Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. September 30, 2015 December 31, 2014 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 580,667 $ 581,281 $ 126,921 $ 127,821 Due after one year through five years 2,017,786 2,022,909 1,627,154 1,632,259 Due after five years through ten years 631,503 634,265 474,959 479,138 Due after ten years 61,583 63,470 43,314 46,720 Residential mortgage-backed securities 1,200,645 1,222,805 1,149,536 1,175,006 Commercial mortgage-backed securities 831,254 837,772 960,598 979,419 Collateralized loan and debt obligations 423,239 418,875 247,510 248,011 Asset-backed securities 610,299 611,736 411,529 413,221 Total $ 6,356,976 $ 6,393,113 $ 5,041,521 $ 5,101,595
Fair Value of Trading Investments	The following table summarizes the fair value of the fixed maturity investments, short-term investments and equity securities classified as trading at September 30, 2015 . The Company had no securities classified as trading as of December 31, 2014 . September 30, 2015 Fixed maturity investments U.S. government and agencies securities $ 208,610 U.S. state and municipal securities 4,625 Foreign government securities 48,562 Government guaranteed corporate securities 40,133 Corporate securities 559,228 Residential mortgage-backed securities 121,302 Commercial mortgage-backed securities 92,906 Collateralized loan and debt obligations (1) 102,976 Asset-backed securities 193,688 Total fixed maturity investments 1,372,030 Short-term investments 348,582 Total fixed income investments $ 1,720,612 Equity securities Equity investments $ 70 Preferred equity investments 2,080 Total equity securities $ 2,150 (1) Balances include amounts related to collateralized debt obligations held with total fair values of $44.1 million at September 30, 2015 .
Other Investments	The following table summarizes the composition and redemption restrictions of other investments as of September 30, 2015 and December 31, 2014 : September 30, 2015 Market Value Unfunded Commitments Ineligible for Redemption over next 12 months Alternative funds Hedge funds $ 641,089 $ — $ 89,387 Private investment funds 82,532 59,763 82,532 Other investment funds 23,577 — 25,011 Total alternative funds 747,198 59,763 196,930 Specialty funds High yield loan funds 95,248 — — Total specialty funds 95,248 — — Total other investments $ 842,446 $ 59,763 $ 196,930 3. Investments, cont'd. December 31, 2014 Market Value Unfunded Ineligible for Alternative funds Hedge funds $ 411,280 $ — $ 10,580 Private investment funds 74,664 70,542 74,664 Total alternative funds 485,944 70,542 85,244 Specialty funds High yield loan funds 55,510 — — Total specialty funds 55,510 — — Total other investments $ 541,454 $ 70,542 $ 85,244
Net Realized And Unrealized Gains	The analysis of net realized and unrealized gains and the change in the fair value of investment-related derivative financial instruments for the three and nine months ended September 30, 2015 and 2014 is as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Gross realized gains on investment sales $ 20,107 $ 10,683 $ 57,420 $ 28,317 Gross realized losses on investment sales (8,236 ) (1,475 ) (18,190 ) (12,778 ) Net unrealized losses on trading securities (5,037 ) — (5,037 ) — Change in fair value of derivative financial instruments (1) (1,805 ) 580 (1,295 ) 2,532 Net realized and unrealized gains $ 5,029 $ 9,788 $ 32,898 $ 18,071 (1) For additional information on the Company's derivative financial instruments, see Note 7, Derivatives.
Amortized Cost, Fair Value, Gross Unrealized Gains and Losses	The amortized cost, fair value and related gross unrealized gains and losses on the Company’s securities classified as available for sale at September 30, 2015 and December 31, 2014 are as follows: September 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Fixed maturity investments U.S. government and agencies securities $ 590,216 $ 8,675 $ (1,358 ) $ 597,533 U.S. state and municipal securities 24,157 262 (108 ) 24,311 Foreign government securities 108,099 1,073 (522 ) 108,650 Government guaranteed corporate securities 25,416 392 (11 ) 25,797 Corporate securities 1,316,038 10,344 (6,844 ) 1,319,538 Residential mortgage-backed securities 1,080,411 23,611 (2,519 ) 1,101,503 Commercial mortgage-backed securities 737,543 10,676 (3,353 ) 744,866 Collateralized loan and debt obligations (1) 316,161 1,214 (1,476 ) 315,899 Asset-backed securities 417,255 1,792 (999 ) 418,048 Total fixed maturity investments 4,615,296 58,039 (17,190 ) 4,656,145 Short-term investments 16,356 — — 16,356 Total fixed income investments $ 4,631,652 $ 58,039 $ (17,190 ) $ 4,672,501 Equity securities Equity investments $ 407,206 $ 2,709 $ (40,460 ) $ 369,455 Emerging market debt funds 61,874 — (3,021 ) 58,853 Convertible funds 46,331 — (477 ) 45,854 Preferred equity investments 15,427 1,847 (326 ) 16,948 Short-term fixed income fund 4,926 — (1 ) 4,925 Total equity securities $ 535,764 $ 4,556 $ (44,285 ) $ 496,035 (1) Balances include amounts related to collateralized debt obligations held with total fair values of $13.2 million . December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Fixed maturity investments U.S. government and agencies securities $ 582,970 $ 6,471 $ (2,030 ) $ 587,411 U.S. state and municipal securities 39,340 191 (118 ) 39,413 Foreign government securities 239,217 2,983 (1,664 ) 240,536 Government guaranteed corporate securities 47,436 675 (9 ) 48,102 Corporate securities 1,354,370 12,742 (5,650 ) 1,361,462 Residential mortgage-backed securities 1,149,536 27,542 (2,072 ) 1,175,006 Commercial mortgage-backed securities 960,598 21,374 (2,553 ) 979,419 Collateralized loan and debt obligations (1) 247,510 1,449 (948 ) 248,011 Asset-backed securities 411,529 2,265 (573 ) 413,221 Total fixed maturity investments 5,032,506 75,692 (15,617 ) 5,092,581 Short-term investments 9,015 — (1 ) 9,014 Total fixed income investments $ 5,041,521 $ 75,692 $ (15,618 ) $ 5,101,595 Equity securities Equity investments $ 176,167 $ 29,660 $ (3,292 ) $ 202,535 Emerging market debt funds 60,826 — (676 ) 60,150 Convertible funds 46,331 — (220 ) 46,111 Preferred equity investments 13,858 2,022 (44 ) 15,836 Short-term fixed income funds 6,740 — (4 ) 6,736 Total equity securities $ 303,922 $ 31,682 $ (4,236 ) $ 331,368 (1) Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million .
Available For Sale Securities In An Unrealized Loss Position	Less than 12 months 12 months or greater Total December 31, 2014 Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Fixed maturity investments U.S. government and agencies securities $ (481 ) $ 155,350 $ (1,549 ) $ 45,993 $ (2,030 ) $ 201,343 U.S. state and municipal securities (47 ) 3,295 (71 ) 6,841 (118 ) 10,136 Foreign government securities (1,378 ) 37,904 (286 ) 4,306 (1,664 ) 42,210 Government guaranteed corporate securities (9 ) 4,598 — — (9 ) 4,598 Corporate securities (4,023 ) 533,139 (1,627 ) 84,278 (5,650 ) 617,417 Residential mortgage-backed securities (260 ) 62,832 (1,812 ) 108,899 (2,072 ) 171,731 Commercial mortgage-backed securities (1,068 ) 180,222 (1,485 ) 78,412 (2,553 ) 258,634 Collateralized loan and debt obligations (876 ) 176,439 (72 ) 6,491 (948 ) 182,930 Asset-backed securities (415 ) 199,205 (158 ) 19,095 (573 ) 218,300 Total fixed maturity investments (8,557 ) 1,352,984 (7,060 ) 354,315 (15,617 ) 1,707,299 Short-term investments (1 ) 1,953 — — (1 ) 1,953 Total fixed income investments $ (8,558 ) $ 1,354,937 $ (7,060 ) $ 354,315 $ (15,618 ) $ 1,709,252 Equity securities Equity investments $ (3,292 ) $ 53,591 $ — $ — $ (3,292 ) $ 53,591 Emerging market debt funds (676 ) 60,150 — — (676 ) 60,150 Convertible funds (220 ) 46,111 — — (220 ) 46,111 Preferred equity investments (44 ) 4,449 — — (44 ) 4,449 Short-term fixed income fund (4 ) 6,736 — — (4 ) 6,736 Total equity securities $ (4,236 ) $ 171,037 $ — $ — $ (4,236 ) $ 171,037 (1) Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at December 31, 2014 . The following tables summarize, for all available for sale securities in an unrealized loss position at September 30, 2015 and December 31, 2014 , the aggregate fair value and gross unrealized loss by length of time the security has continuously been in an unrealized loss position. Less than 12 months 12 months or greater Total September 30, 2015 Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Unrealized Losses (1) Fair Value Fixed maturity investments U.S. government and agencies securities $ (438 ) $ 71,512 $ (920 ) $ 21,859 $ (1,358 ) $ 93,371 U.S. state and municipal securities (44 ) 2,311 (64 ) 708 (108 ) 3,019 Foreign government securities (442 ) 24,977 (80 ) 4,558 (522 ) 29,535 Government guaranteed corporate securities (11 ) 1,737 — — (11 ) 1,737 Corporate securities (5,687 ) 493,115 (1,157 ) 44,942 (6,844 ) 538,057 Residential mortgage-backed securities (1,300 ) 174,347 (1,219 ) 75,619 (2,519 ) 249,966 Commercial mortgage-backed securities (1,853 ) 214,560 (1,500 ) 45,802 (3,353 ) 260,362 Collateralized loan and debt obligations (1,075 ) 193,044 (401 ) 44,551 (1,476 ) 237,595 Asset-backed securities (807 ) 162,488 (192 ) 17,011 (999 ) 179,499 Total fixed income investments $ (11,657 ) $ 1,338,091 $ (5,533 ) $ 255,050 $ (17,190 ) $ 1,593,141 Equity securities Equity investments $ (40,460 ) $ 321,413 $ — $ — $ (40,460 ) $ 321,413 Emerging market debt funds (3,021 ) 58,853 — — (3,021 ) 58,853 Convertible funds (477 ) 45,854 — — (477 ) 45,854 Preferred equity investments (326 ) 9,027 — — (326 ) 9,027 Short-term fixed income fund (1 ) 4,924 — — (1 ) 4,924 Total equity securities $ (44,285 ) $ 440,071 $ — $ — $ (44,285 ) $ 440,071 (1) Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at September 30, 2015 .
Noncontrolling Interests Rollforward	The following table summarizes the movements in the non-controlling interests balance during the three months ended September 30, 2015 : Three Months Ended September 30, 2015 Non-controlling interests acquired July 31, 2015 $ 258,529 Income attributable to third-party investments in the BCGR Cell 821 Income attributable to third-party investments in BCRH 1,886 Net income attributable to non-controlling interests 2,707 Net third-party investments in BCRH (7 ) Dividends declared by BCRH attributable to non-controlling interests (1,755 ) Non-controlling interests - ending balance $ 259,474

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Schedule Of Fixed Maturity Investments, Equity Securities, Short-term Investments, Other Investments, Derivative Instruments And Debt Measured On A Recurring Basis	The following table sets forth the Company’s fixed maturity investments, equity securities, short-term investments, other investments, other assets and liabilities and debt categorized by the level within the hierarchy in which the fair value measurements fall at December 31, 2014 : Fair Value Measurements at December 31, 2014 Total at December 31, 2014 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Fixed maturity investments U.S. government and agencies securities $ 587,411 $ 105,121 $ 482,290 $ — U.S. state and municipal securities 39,413 — 39,413 — Foreign government securities 240,536 — 240,536 — Government guaranteed corporate securities 48,102 — 48,102 — Corporate securities 1,361,462 — 1,358,960 2,502 Residential mortgage-backed securities 1,175,006 — 1,174,997 9 Commercial mortgage-backed securities 979,419 — 974,602 4,817 Collateralized loan and debt obligations 248,011 — 246,042 1,969 Asset-backed securities 413,221 — 410,228 2,993 Total fixed maturity investments 5,092,581 105,121 4,975,170 12,290 Equity securities Equity investments 202,535 138,463 64,072 — Emerging market debt funds 60,150 — 60,150 — Convertible funds 46,111 — 46,111 — Preferred equity investments 15,836 — 15,836 — Short-term fixed income fund 6,736 6,736 — — Total equity securities 331,368 145,199 186,169 — Short-term investments 9,014 — 9,014 — Other investments 541,454 — — 541,454 Other assets (see Note 7) 99,504 — 73,889 25,615 Total assets $ 6,073,921 $ 250,320 $ 5,244,242 $ 579,359 Liabilities Other liabilities (see Note 7) $ 54,338 $ — $ 18,972 $ 35,366 Debt 623,740 — 623,740 — Total liabilities $ 678,078 $ — $ 642,712 $ 35,366 The following table sets forth the Company's fixed maturity investments, equity securities, short-term investments, other investments, other assets and liabilities and debt categorized by the level within the hierarchy in which the fair value measurements fall at September 30, 2015 : Fair Value Measurements at September 30, 2015 Total at September 30, 2015 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Fixed maturity investments U.S. government and agencies securities $ 806,143 $ 48,589 $ 757,554 $ — U.S. state and municipal securities 28,936 — 28,936 — Foreign government securities 157,212 — 157,212 — Government guaranteed corporate securities 65,930 — 65,930 — Corporate securities 1,878,766 — 1,750,877 127,889 Residential mortgage-backed securities 1,222,805 — 1,222,680 125 Commercial mortgage-backed securities 837,772 — 835,321 2,451 Collateralized loan and debt obligations 418,875 — 415,964 2,911 Asset-backed securities 611,736 — 611,736 — Total fixed maturity investments 6,028,175 48,589 5,846,210 133,376 Equity securities Equity investments 369,525 239,188 130,337 — Emerging market debt funds 58,853 — 58,853 — Convertible funds 45,854 — 45,854 — Preferred equity investments 19,028 — 19,028 — Short-term fixed income fund 4,925 4,925 — — Total equity securities 498,185 244,113 254,072 — Short-term investments 364,938 — 364,938 — Other investments 842,446 — — 842,446 Other assets (see Note 7) 80,395 — 60,218 20,177 Total assets $ 7,814,139 $ 292,702 $ 6,525,438 $ 995,999 Liabilities Other liabilities (see Note 7) $ 53,534 $ — $ 33,809 $ 19,725 Debt 968,248 — 968,248 — Total liabilities $ 1,021,782 $ — $ 1,002,057 $ 19,725
Fair Value Inputs Assets And Liabilities Quantitative Information [Table Text Block]	Below is a summary of quantitative information regarding the significant unobservable inputs used in determining the fair value of the net weather and energy related derivative assets and liabilities classified in Level 3 that are measured at fair value on a recurring basis at September 30, 2015 and December 31, 2014 : September 30, 2015 Fair Value (Level 3) Valuation Techniques Unobservable Inputs Low High Weighted Average or Actual (U.S. dollars in thousands, except for correlation) Net weather and energy related derivative assets $ 452 Historical Analysis and Simulation Correlation 0 1 Actual Weather curve $ 2,200 $ 10,600 Actual Commodity curve $ — $ 13 Actual December 31, 2014 Fair Value (Level 3) Valuation Techniques Unobservable Inputs Low High Weighted Average or Actual (U.S. dollars in thousands, except for correlation) Net weather and energy related derivative liabilities $ 9,751 Historical Analysis and Simulation Correlation 0 1 Actual Weather curve $ (828 ) $ 2,500 Actual Commodity curve $ — $ 13 Actual
Reconciliation Of The Beginning And Ending Balances For All Investments And Derivative Instruments Measured At Fair Value On A Recurring Basis Using Level 3 Inputs	The following tables present a reconciliation of the beginning and ending balances for all assets and liabilities measured at fair value on a recurring basis using Level 3 inputs during the three months ended September 30, 2015 and 2014 : Three Months Ended September 30, 2015 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 4,707 $ 623,868 $ 23,691 $ 652,266 $ (22,184 ) Total equity income and realized gains included in earnings — 10,031 — 10,031 — Total equity losses and losses included in earnings (24 ) (22,463 ) — (22,487 ) — Total income included in other underwriting income (loss) — — 1,589 1,589 14,745 Total loss included in other underwriting income (loss) — — (11,794 ) (11,794 ) (2,552 ) Change in unrealized gains included in other comprehensive (loss) income 85 — — 85 — Change in unrealized losses included in other comprehensive (loss) income (35 ) — — (35 ) — Purchases — 12,116 1,250 13,366 (737 ) Issues — — 5,441 5,441 (9,058 ) Sales (237 ) (13,243 ) — (13,480 ) — Settlements — — — — 61 Transfers in to Level 3 128,880 232,137 — 361,017 — Transfers out of Level 3 — — — — — Level 3, end of period $ 133,376 $ 842,446 $ 20,177 $ 995,999 $ (19,725 ) Three Months Ended September 30, 2014 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 9,515 $ 648,642 $ 10,992 $ 669,149 $ (10,284 ) Total equity income and realized gains included in earnings 9 10,913 — 10,922 — Total equity losses and losses included in earnings (6 ) (12,698 ) — (12,704 ) — Total income included in other underwriting income (loss) — — 3,180 3,180 4,794 Total loss included in other underwriting income (loss) — — (5,235 ) (5,235 ) (3,719 ) Change in unrealized gains included in other comprehensive (loss) income 245 — — 245 — Change in unrealized losses included in other comprehensive (loss) income (104 ) — — (104 ) — Purchases 842 26,190 1,501 28,533 (751 ) Issues — — 7,331 7,331 (10,917 ) Sales (545 ) (14,369 ) — (14,914 ) — Settlements — — (2,947 ) (2,947 ) 4,961 Transfers in to Level 3 2,198 — — 2,198 — Transfers out of Level 3 (4,961 ) — — (4,961 ) — Level 3, end of period $ 7,193 $ 658,678 $ 14,822 $ 680,693 $ (15,916 ) The following tables present a reconciliation of the beginning and ending balances for all assets and liabilities measured at fair value on a recurring basis using Level 3 inputs during the nine months ended September 30, 2015 and 2014 : Nine Months Ended September 30, 2015 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 12,290 $ 541,454 $ 25,615 $ 579,359 $ (35,366 ) Total equity income and realized gains included in earnings 113 45,049 — 45,162 — Total equity losses and losses included in earnings (35 ) (41,523 ) — (41,558 ) — Total income included in other underwriting income (loss) — — 7,184 7,184 35,610 Total loss included in other underwriting income (loss) — — (24,788 ) (24,788 ) (9,772 ) Change in unrealized gains included in other comprehensive (loss) income 109 — — 109 — Change in unrealized losses included in other comprehensive (loss) income (228 ) — — (228 ) — Purchases — 115,095 1,250 116,345 (737 ) Issues — — 17,774 17,774 (27,806 ) Sales (547 ) (49,766 ) — (50,313 ) — Settlements — — (6,858 ) (6,858 ) 18,346 Transfers in to Level 3 130,850 232,137 — 362,987 — Transfers out of Level 3 (9,176 ) — — (9,176 ) — Level 3, end of period $ 133,376 $ 842,446 $ 20,177 $ 995,999 $ (19,725 ) Nine Months Ended September 30, 2014 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 7,328 $ 617,478 $ 14,038 $ 638,844 $ (19,569 ) Total equity income and realized gains included in earnings 62 46,385 — 46,447 — Total equity losses and losses included in earnings (32 ) (23,844 ) — (23,876 ) — Total income included in other underwriting income (loss) — — 18,396 18,396 24,842 Total loss included in other underwriting income (loss) — — (23,845 ) (23,845 ) (20,672 ) Change in unrealized gains included in other comprehensive income (loss) 445 — — 445 — Change in unrealized losses included in other comprehensive income (loss) (255 ) — — (255 ) — Purchases 842 52,731 1,501 55,074 (751 ) Issues — — 10,912 10,912 (18,080 ) Sales (1,585 ) (34,072 ) — (35,657 ) — Settlements — — (6,180 ) (6,180 ) 18,314 Transfers in to Level 3 7,201 — — 7,201 — Transfers out of Level 3 (6,813 ) — — (6,813 ) — Level 3, end of period $ 7,193 $ 658,678 $ 14,822 $ 680,693 $ (15,916 )

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Schedule Of Computation Of Basic And Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per Endurance Holdings common share for the three and nine months ended September 30, 2015 and 2014 : Three Months Ended Nine Months Ended 2015 2014 2015 2014 Numerator: Net income available to Endurance Holdings common and participating common shareholders $ 43,635 $ 68,046 $ 219,944 $ 239,313 Less amount allocated to participating common shareholders (1) (1,251 ) (1,930 ) (6,442 ) (6,907 ) Net income allocated to Endurance Holdings common shareholders $ 42,384 $ 66,116 $ 213,502 $ 232,406 Denominator: Weighted average shares - basic 57,923,044 43,464,790 48,453,368 43,332,461 Share equivalents: Options 111,760 45,625 137,366 23,237 Restricted shares and restricted share units 11,344 — 1,367 94 Weighted average shares - diluted 58,046,148 43,510,415 48,592,101 43,355,792 Basic earnings per Endurance Holdings common share $ 0.73 $ 1.52 $ 4.41 $ 5.36 Diluted earnings per Endurance Holdings common share $ 0.73 $ 1.52 $ 4.39 $ 5.36 (1) Represents earnings attributable to holders of unvested restricted shares and restricted share units issued under the Company's equity compensation plan that are considered participating. In periods of loss, no losses are allocated to participating common shareholders (unvested restricted shares and restricted share units).
Schedule Of Dividends Declared	Three Months Ended Nine Months Ended 2015 2014 2015 2014 Dividends declared per Series A preferred share $ 0.484375 $ 0.484375 $ 1.453125 $ 1.453125 Dividends declared per Series B preferred share $ 0.468750 $ 0.468750 $ 1.406250 $ 1.406250 Dividends declared per common share $ 0.35 $ 0.34 $ 1.05 $ 1.02

Accumulated Other Comprehensi31

Accumulated Other Comprehensive (Loss) Income (Tables)	9 Months Ended
	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule Of Accumulated Other Comprehensive (Loss) Income	The following tables present the changes in accumulated other comprehensive (loss) income balances by component for the three months ended September 30, 2015 and 2014 : For the Three Months Ended September 30, 2015 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,722 ) $ 43,610 $ (4,923 ) $ 36,965 Other comprehensive (loss) income before reclassifications — (18,258 ) (15,625 ) (33,883 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) 22 (11,648 ) — (11,626 ) Net current period other comprehensive (loss) income 22 (29,906 ) (15,625 ) (45,509 ) Ending balance $ (1,700 ) $ 13,704 $ (20,548 ) $ (8,544 ) (1) All amounts are net of tax. For the Three Months Ended September 30, 2014 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,810 ) 106,989 $ 30,859 $ 136,038 Other comprehensive (loss) income before reclassifications — (25,446 ) (20,404 ) (45,850 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) 22 (8,911 ) — (8,889 ) Net current period other comprehensive (loss) income 22 (34,357 ) (20,404 ) (54,739 ) Ending balance $ (1,788 ) $ 72,632 $ 10,455 $ 81,299 (1) All amounts are net of tax. 6. Accumulated other comprehensive (loss) income, cont'd. The following tables present the changes in accumulated other comprehensive (loss) income balances by component for the nine months ended September 30, 2015 and 2014 : For the Nine Months Ended September 30, 2015 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,766 ) $ 86,100 $ (7,628 ) $ 76,706 Other comprehensive (loss) income before reclassifications — (35,195 ) (12,920 ) (48,115 ) Amounts reclassified from accumulated other comprehensive (loss) income (1) 66 (37,201 ) — (37,135 ) Net current period other comprehensive (loss) income 66 (72,396 ) (12,920 ) (85,250 ) Ending balance $ (1,700 ) $ 13,704 $ (20,548 ) $ (8,544 ) (1) All amounts are net of tax. For the Nine Months Ended September 30, 2014 Losses on cash flow hedges Unrealized (losses) gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,855 ) $ 45,950 $ 18,636 $ 62,731 Other comprehensive (loss) income before reclassifications — 41,895 (8,181 ) 33,714 Amounts reclassified from accumulated other comprehensive (loss) income (1) 67 (15,213 ) — (15,146 ) Net current period other comprehensive (loss) income 67 26,682 (8,181 ) 18,568 Ending balance $ (1,788 ) $ 72,632 $ 10,455 $ 81,299 (1) All amounts are net of tax.
Reclassification Out Of Accumulated Other Comprehensive Income	The following tables present the significant items reclassified out of accumulated other comprehensive (loss) income during the three months ended September 30, 2015 and 2014 : Three Months Ended September 30, 2015 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 22 Interest expense 22 Total before income taxes — Income tax expense $ 22 Total net of income taxes Unrealized gains on available for sale securities $ (11,871 ) Net realized and unrealized gains 38 Net impairment losses recognized in earnings (11,833 ) Total before income taxes 185 Income tax expense $ (11,648 ) Total net of income taxes Three Months Ended September 30, 2014 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 22 Interest expense 22 Total before income taxes — Income tax expense $ 22 Total net of income taxes Unrealized gains on available for sale securities $ (9,208 ) Net realized and unrealized gains 102 Net impairment losses recognized in earnings (9,106 ) Total before income taxes 195 Income tax expense $ (8,911 ) Total net of income taxes The following tables present the significant items reclassified out of accumulated other comprehensive (loss) income during the nine months ended September 30, 2015 and 2014 : Nine Months Ended September 30, 2015 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 66 Interest expense 66 Total before income taxes — Income tax expense $ 66 Total net of income taxes Unrealized gains on available for sale securities $ (39,230 ) Net realized and unrealized gains 1,111 Net impairment losses recognized in earnings (38,119 ) Total before income taxes 918 Income tax expense $ (37,201 ) Total net of income taxes Nine Months Ended September 30, 2014 Details about accumulated other comprehensive (loss) income components Amount reclassified from accumulated other comprehensive (loss) income Affected line item in the Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 67 Interest expense 67 Total before income taxes — Income tax expense $ 67 Total net of income taxes Unrealized gains on available for sale securities $ (15,539 ) Net realized and unrealized gains 411 Net impairment losses recognized in earnings (15,128 ) Total before income taxes (85 ) Income tax benefit $ (15,213 ) Total net of income taxes

Derivatives (Tables)

Derivatives (Tables)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule Of The Fair Value And Related Notional Amounts Of Derivatives Included In The Company's Consolidated Balance Sheet	The fair values and the related notional values of derivatives at September 30, 2015 and December 31, 2014 are shown below. September 30, 2015 December 31, 2014 Fair Value Notional Principal Amount Fair Value Notional Principal Amount Derivatives recorded in other assets Foreign exchange forward contracts $ 663 $ 49,845 $ 651 $ 42,694 Credit default swaps 17 4,290 — — Interest rate swaps 156 4,000 — — Interest rate futures 8 54,659 7 7,595 ILWs 536 12,500 — — TBAs 58,838 55,000 73,231 70,000 Energy and weather contracts 20,177 70,143 25,615 81,624 Total recorded in other assets $ 80,395 $ 99,504 Derivatives recorded in other liabilities Foreign exchange forward contracts $ 418 $ 24,832 $ 123 $ 20,945 Credit default swaps 322 6,600 — — Interest rate swaps 198 40,100 20 12,549 Interest rate swaptions — — 9 13,100 Interest rate futures 3 9,762 — — ILWs 1,120 19,500 — — LIBOR swap 738 100,000 — — TBAs 31,010 29,000 18,820 18,000 Energy and weather contracts 19,725 112,435 35,366 135,050 Total recorded in other liabilities $ 53,534 $ 54,338 Net derivative asset $ 26,861 $ 45,166
Schedule Of The Gains And Losses On The Consolidated Statements Of Income And Comprehensive Income From Derivatives	The gains and losses on the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income for derivatives for the three and nine months ended September 30, 2015 and 2014 were as follows: Three Months Ended Nine Months Ended 2015 2014 2015 2014 Total gain included in net foreign exchange losses from foreign exchange forward contracts $ 155 $ 1,214 $ 1,281 $ 815 Interest rate futures (78 ) — 17 136 Credit default swaps (143 ) 6 (134 ) 20 Interest rate swaps (705 ) 384 (940 ) (698 ) Interest rate swaptions 28 (3 ) 56 425 ILWs (652 ) — (652 ) — LIBOR swap (173 ) — (173 ) — TBAs (82 ) 193 531 2,649 Total (losses) gains included in net realized and unrealized gains (1,805 ) 580 (1,295 ) 2,532 Total gain included in other underwriting income (loss) from energy and weather contracts 1,988 1,784 8,030 1,486 Total gains from derivatives $ 338 $ 3,578 $ 8,016 $ 4,833

Stock-Based Employee Compensa33

Stock-Based Employee Compensation And Other Stock Plans (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]	A summary of the restricted share and restricted share unit activity during the nine months ended September 30, 2015 , is presented below: Number of Shares/Units Aggregate Intrinsic Value Unvested, beginning of period 1,290,894 Granted and assumed 1,360,981 Settled (776,614 ) Forfeited (17,701 ) Unvested, end of period 1,857,560 Outstanding, end of period 1,857,560 $ 113,367

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Summary Of The Segment Revenues, Results, Reserve For Losses And Loss Expenses And Goodwill	The following table provides a summary of segment revenues, results, reserves for losses and loss expenses and goodwill for the three months ended September 30, 2014 : Three Months Ended September 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 420,343 $ 205,767 $ 626,110 Ceded premiums written (222,704 ) (13,300 ) (236,004 ) Net premiums written 197,639 192,467 390,106 Net premiums earned 253,583 261,312 514,895 Other underwriting income — 2,123 2,123 253,583 263,435 517,018 Expenses Net losses and loss expenses 196,677 93,592 290,269 Acquisition expenses 20,170 73,222 93,392 General and administrative expenses 40,401 28,545 68,946 257,248 195,359 452,607 Underwriting (loss) income $ (3,665 ) $ 68,076 64,411 Net investment income 25,357 Corporate expenses (11,969 ) Net foreign exchange losses (783 ) Net realized and unrealized gains 9,788 Net impairment losses recognized in earnings (102 ) Amortization of intangibles (1,623 ) Interest expense (13,127 ) Income before income taxes $ 71,952 Net loss ratio 77.5 % 35.8 % 56.4 % Acquisition expense ratio 8.0 % 28.0 % 18.1 % General and administrative expense ratio 15.9 % 11.0 % 15.7 % (1) Combined ratio 101.4 % 74.8 % 90.2 % Reserve for losses and loss expenses $ 2,134,985 $ 1,762,498 $ 3,897,483 Goodwill $ 47,925 $ 43,401 $ 91,326 (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses. The following table provides a summary of segment revenues, results, reserves for losses and loss expenses and goodwill for the three months ended September 30, 2015 : Three Months Ended September 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 448,563 $ 194,034 $ 642,597 Ceded premiums written (273,626 ) (32,281 ) (305,907 ) Net premiums written 174,937 161,753 336,690 Net premiums earned 234,143 322,860 557,003 Other underwriting income — 227 227 234,143 323,087 557,230 Expenses Net losses and loss expenses 139,141 124,852 263,993 Acquisition expenses 24,375 66,082 90,457 General and administrative expenses 31,880 28,913 60,793 195,396 219,847 415,243 Underwriting income $ 38,747 $ 103,240 141,987 Net investment income 16,533 Corporate expenses (74,308 ) Net foreign exchange losses (8,621 ) Net realized and unrealized gains 5,029 Net impairment losses recognized in earnings (38 ) Amortization of intangibles (11,318 ) Interest expense (12,324 ) Income before income taxes $ 56,940 Net loss ratio 59.5 % 38.6 % 47.4 % Acquisition expense ratio 10.4 % 20.5 % 16.2 % General and administrative expense ratio 13.6 % 9.0 % 24.3 % (1) Combined ratio 83.5 % 68.1 % 87.9 % Reserve for losses and loss expenses $ 2,442,821 $ 2,047,015 $ 4,489,836 Goodwill $ 85,179 $ 92,247 $ 177,426 (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses. The following table provides a summary of the segment revenues and results for the nine months ended September 30, 2015 : Nine Months Ended September 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 1,653,647 $ 1,151,566 $ 2,805,213 Ceded premiums written (984,372 ) (160,114 ) (1,144,486 ) Net premiums written 669,275 991,452 1,660,727 Net premiums earned 571,467 833,530 1,404,997 Other underwriting income — 4,022 4,022 571,467 837,552 1,409,019 Expenses Net losses and loss expenses 359,136 315,915 675,051 Acquisition expenses 57,960 199,561 257,521 General and administrative expenses 89,289 81,359 170,648 506,385 596,835 1,103,220 Underwriting income $ 65,082 $ 240,717 305,799 Net investment income 90,646 Corporate expenses (99,210 ) Net foreign exchange losses (29,154 ) Net realized and unrealized gains 32,898 Net impairment losses recognized in earnings (1,111 ) Amortization of intangibles (14,496 ) Interest expense (30,445 ) Income before income taxes $ 254,927 Net loss ratio 62.9 % 37.9 % 48.1 % Acquisition expense ratio 10.1 % 23.9 % 18.3 % General and administrative expense ratio 15.6 % 9.8 % 19.2 % (1) Combined ratio 88.6 % 71.6 % 85.6 % (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses. 9. Segment reporting, cont'd. The following table provides a summary of the segment revenues and results for the nine months ended September 30, 2014 : Nine Months Ended September 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 1,394,145 $ 1,078,905 $ 2,473,050 Ceded premiums written (674,441 ) (98,371 ) (772,812 ) Net premiums written 719,704 980,534 1,700,238 Net premiums earned 616,167 776,532 1,392,699 Other underwriting loss — (3,939 ) (3,939 ) 616,167 772,593 1,388,760 Expenses Net losses and loss expenses 434,777 291,584 726,361 Acquisition expenses 47,559 196,591 244,150 General and administrative expenses 113,069 73,690 186,759 595,405 561,865 1,157,270 Underwriting income $ 20,762 $ 210,728 231,490 Net investment income 105,649 Corporate expenses (53,817 ) Net foreign exchange losses (4,066 ) Net realized and unrealized gains 18,071 Net impairment losses recognized in earnings (411 ) Amortization of intangibles (4,863 ) Interest expense (31,910 ) Income before income taxes $ 260,143 Net loss ratio 70.6 % 37.6 % 52.2 % Acquisition expense ratio 7.7 % 25.3 % 17.5 % General and administrative expense ratio 18.3 % 9.5 % 17.3 % (1) Combined ratio 96.6 % 72.4 % 87.0 % (1) Total general and administrative expense ratio includes general and administrative expenses and corporate expenses.
Schedule Of Gross And Net Premiums Written By Line Of Business	The following table provides gross and net premiums written by line of business for the three months ended September 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 156,145 $ 29,634 $ 188,011 $ 103,536 Casualty and other specialty 128,509 64,490 115,895 50,750 Professional lines 80,069 37,479 62,631 20,216 Property, marine and energy 83,840 43,334 53,806 23,137 Total Insurance 448,563 174,937 420,343 197,639 Reinsurance Catastrophe 40,660 14,814 47,173 41,157 Property 53,423 52,887 73,807 73,807 Casualty 42,802 42,802 23,409 23,409 Professional lines 31,705 31,705 21,520 21,520 Specialty 25,444 19,545 39,858 32,574 Total Reinsurance 194,034 161,753 205,767 192,467 Total $ 642,597 $ 336,690 $ 626,110 $ 390,106 The following table provides gross and net premiums written by line of business for the nine months ended September 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 785,073 $ 254,771 $ 796,445 $ 431,007 Casualty and other specialty 375,247 174,850 291,578 144,038 Professional lines 231,565 105,153 176,061 64,632 Property, marine and energy 261,762 134,501 130,061 80,027 Total Insurance 1,653,647 669,275 1,394,145 719,704 Reinsurance Catastrophe 304,900 190,579 332,193 243,531 Property 209,683 206,454 283,107 283,015 Casualty 149,032 149,032 139,266 137,669 Professional lines 209,803 209,803 131,256 131,256 Specialty 278,148 235,584 193,083 185,063 Total Reinsurance 1,151,566 991,452 1,078,905 980,534 Total $ 2,805,213 $ 1,660,727 $ 2,473,050 $ 1,700,238

Commitments And Contingencies (

Commitments And Contingencies (Tables)	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule Of Percentage Of Net Premiums Written	The following table shows the percentage of net premiums written generated through the Company’s largest brokers for the nine months ended September 30, 2015 and 2014 , respectively: Broker 2015 2014 Marsh & McLennan Companies, Inc. 24.9 % 20.9 % Aon Benfield 15.8 % 15.4 % Willis Companies 12.8 % 14.2 % Total of largest brokers 53.5 % 50.5 %
Schedule Of Future Minimum Lease Commitments	Future minimum lease commitments at September 30, 2015 are as follows: Twelve months ended September 30, Amount 2016 $ 17,657 2017 16,415 2018 16,425 2019 15,825 2020 14,795 2021 and thereafter 30,894 $ 112,011

Acquisition of Montpelier (Tabl

Acquisition of Montpelier (Tables)	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	The Company's total purchase price for Montpelier at July 31, 2015 was calculated as follows: Consideration paid by Endurance Number of Montpelier common shares outstanding immediately prior to the closing of the acquisition 43,827,753 Exchange ratio 0.472 Total Company ordinary shares 20,686,699 Company ordinary share closing price on July 31, 2015 $ 69.49 Total value of Company ordinary shares $ 1,437,519 Fair value of restricted share units attributable to service period prior to merger date (1) $ 33,327 Total consideration $ 1,470,846 Special Dividend paid by Montpelier Number of Montpelier common shares and restricted share units eligible for special dividend 45,611,810 Special dividend paid per Montpelier common share and restricted share unit $ 9.89 Total special dividend consideration paid to Montpelier common shareholders $ 451,101 Total consideration received by Montpelier common shareholders $ 1,921,947 Less: Special Dividend paid by Montpelier (451,101 ) Net purchase price $ 1,470,846 (1) Outstanding Montpelier restricted share units were assumed by the Company and adjusted as of the Closing Date to represent the right to receive 0.472 Company ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of Company ordinary shares. The fair value of the Montpelier restricted share units was determined based on the closing price of the Company's ordinary shares on the Closing Date. The resulting fair value of the restricted share units was apportioned as purchase consideration based on service provided to Montpelier as of the Closing Date with the remaining fair value of these restricted share units to be recognized prospectively over the restricted share units' remaining vesting period. The following table summarizes the results of Montpelier since July 31, 2015 that have been included in the Company's Condensed Consolidated Statement of Income and Comprehensive Income for the three and nine months ended September 30, 2015 and the Company's Condensed Consolidated Balance Sheet as at September 30, 2015 . For the period from July 31, 2015 to September 30, 2015 Total revenues $ 94,249 Net loss attributable to the Company's common shareholders (1) (10,058 ) (1) Includes $48.2 million of compensation-related costs associated with terminating employees of Montpelier.
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The Company identified finite lived intangible assets of $293.2 million , which will be amortized over a weighted average period of 8 years, identifiable indefinite lived intangible assets of $57.6 million , and certain other adjustments to the fair values of the assets acquired, liabilities assumed and shareholders' equity of Montpelier at September 30, 2015 as summarized in the table below: Montpelier shareholders' equity attributable to controlling interest prior to Special Dividend $ 1,560,255 Cash and cash equivalents (Special Dividend on Montpelier common shares and Montpelier equity awards) (451,101 ) Adjusted shareholders' equity of Montpelier as of July 31, 2015 1,109,154 Adjustments for fair value, by applicable balance sheet caption: Assets: Fixed maturity investments, trading at fair value (11,100 ) Deferred acquisition costs (91,713 ) Reinsurance recoverable on unpaid losses (675 ) Other assets (12,459 ) Liabilities: Reserve for losses and loss expenses 10,822 Debt 21,123 Deferred tax liability (18,346 ) Equity: Non-controlling interest 25,615 Total adjustments for fair value by applicable balance sheet caption (76,733 ) Adjustments for fair value of the identifiable intangible assets: Identifiable indefinite lived intangible assets (insurance licenses, Lloyd's syndicate capacity and asset management agreements) 57,600 Identifiable finite lived intangible assets (non-contractual relationships, Lloyd's syndicate distribution channel, renewal rights, value of business acquired, trademarks and trade names, covenants not to compete and asset management agreements) 293,200 Total adjustments for fair value by applicable balance sheet caption and identifiable intangible assets 274,067 Estimated fair value of net assets acquired and identifiable intangible assets 1,383,221 Total consideration paid by Endurance Holdings 1,470,846 Estimated total consideration over the fair value of net assets acquired assigned to goodwill $ 87,625
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]	Identifiable intangible assets at July 31, 2015 consisted of the following, and are included in goodwill and other intangible assets on the Company's consolidated balance sheets: Amount Economic Useful Life Key non-contractual relationships $ 71,800 10 Other non-contractual relationships 22,400 3 Trade names 1,800 Various Insurance licenses 1,900 Indefinite Non-compete agreements 5,700 Various Lloyd's syndicate capacity 48,300 Indefinite Lloyd's syndicate distribution channel 18,400 10 Renewal rights 82,100 15 Value of business acquired 88,400 2 Asset management agreements 10,000 Various Identifiable intangible assets, before amortization, at July 31, 2015 350,800 Amortization (from July 31, 2015 through September 30, 2015) (9,734 ) Net identifiable intangible assets at September 30, 2015 related to the acquisition of Montpelier $ 341,066
Schedule of Goodwill [Table Text Block]	The following table reconciles the carrying amount of goodwill from December 31, 2014 to September 30, 2015: Nine Months Ended September 30, 2015 Balance at December 31, 2014 $ 91,238 Additions 87,625 Foreign currency translation (1,437 ) Balance at September 30, 2015 $ 177,426
Business Acquisition, Pro Forma Information [Table Text Block]	The following table presents unaudited pro forma consolidated financial information for the three and nine months ended September 30, 2015 and 2014 and assumes the acquisition of Montpelier occurred on January 1, 2014. The unaudited pro forma consolidated financial information is provided for informational purposes only and is not necessarily, and should not be assumed to be, an indication of the results that would have been achieved had the transaction been completed as of January 1, 2014 or that may be achieved in the future. The unaudited pro forma consolidated financial information does not give consideration to the impact of possible revenue enhancements, expense efficiencies, synergies or asset dispositions that may result from the acquisition of Montpelier. In addition, unaudited pro forma consolidated financial information does not include the effects of costs associated with any restructuring or integration activities resulting from the acquisition of Montpelier, as they are nonrecurring. Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Total revenues $ 627,394 $ 701,332 $ 1,886,038 $ 2,030,119 Net income available to Endurance Holdings' common shareholders 100,046 86,755 345,086 264,799

Investments (Narrative) (Detail

Investments (Narrative) (Details) $ in Millions	Sep. 30, 2015USD ($)		Dec. 31, 2014USD ($)
Investments [Abstract]
Number of available for sale securities in an unrealized loss position	920		747
Number of securities in a continuous unrealized loss position for twelve months or greater	140		171
Unrealized losses	$ 61.5	[1]	$ 19.9	[2]
Unrealized losses, 12 months or greater	$ 5.5	[1]	$ 7.1	[2]
[1]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at September 30, 2015.
[2]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at December 31, 2014.

Investments (Composition Of Net

Investments (Composition Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Net Investment Income [Line Items]
Investment income before investment expenses	$ 20,751	$ 28,755	$ 101,695	$ 116,325
Investment expenses	(4,218)	(3,398)	(11,049)	(10,676)
Net investment income	16,533	25,357	90,646	105,649
Fixed income investments
Net Investment Income [Line Items]
Investment income before investment expenses	36,204	28,944	96,145	88,616
Equity investments
Net Investment Income [Line Items]
Investment income before investment expenses	1,748	1,015	5,200	3,289
Other investments
Net Investment Income [Line Items]
Investment income before investment expenses	(17,716)	(1,785)	(1,758)	22,542
Cash and cash equivalents
Net Investment Income [Line Items]
Investment income before investment expenses	$ 515	$ 581	$ 2,108	$ 1,878

Investments (Contractual Maturi

Investments (Contractual Maturities Of Fixed Income Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale and Trading Securities [Line Items]
Due within one year, amortized cost	$ 580,667	$ 126,921
Due within one year, fair value	581,281	127,821
Due after one year through five years, amortized cost	2,017,786	1,627,154
Due after one year through five years, fair value	2,022,909	1,632,259
Due after five years through ten years, amortized cost	631,503	474,959
Due after five years through ten years, fair value	634,265	479,138
Due after ten years, amortized cost	61,583	43,314
Due after ten years, fair value	63,470	46,720
Residential mortgage-backed securities
Schedule of Available-for-sale and Trading Securities [Line Items]
No single maturity date, amortized cost	1,200,645	1,149,536
No single maturity date, fair value	1,222,805	1,175,006
Fixed income investments, fair value	1,222,805	1,175,006
Commercial mortgage-backed securities
Schedule of Available-for-sale and Trading Securities [Line Items]
No single maturity date, amortized cost	831,254	960,598
No single maturity date, fair value	837,772	979,419
Fixed income investments, fair value	837,772	979,419
Collateralized loan and debt obligations
Schedule of Available-for-sale and Trading Securities [Line Items]
No single maturity date, amortized cost	423,239	247,510
No single maturity date, fair value	418,875	248,011
Fixed income investments, fair value	418,875	248,011
Asset-backed securities
Schedule of Available-for-sale and Trading Securities [Line Items]
No single maturity date, amortized cost	610,299	411,529
No single maturity date, fair value	611,736	413,221
Fixed income investments, fair value	611,736	413,221
Fixed income investments
Schedule of Available-for-sale and Trading Securities [Line Items]
Fixed income investments, amortized cost	6,356,976	5,041,521
Fixed income investments, fair value	$ 6,393,113	$ 5,101,595

Investments Investments (Fair V

Investments Investments (Fair Value of Trading Investments) (Details) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		$ 1,372,030	$ 0
Short-term investments, trading at fair value		348,582	0
Equity securities, trading at fair value		2,150	$ 0
U.S. government and agencies securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		208,610
U.S. state and municipal securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		4,625
Foreign government securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		48,562
Government guaranteed corporate securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		40,133
Corporate securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		559,228
Residential mortgage-backed securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		121,302
Commercial mortgage-backed securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		92,906
Collateralized loan and debt obligations(1)
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value	[1]	102,976
Asset-backed securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		193,688
Fixed maturity investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		1,372,030
Fixed income investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		1,720,612
Equity investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Equity securities, trading at fair value		70
Preferred equity investments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Equity securities, trading at fair value		2,080
Collateralized debt obligations
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fixed maturity investments, trading at fair value		$ 44,100
[1]	Balances include amounts related to collateralized debt obligations held with total fair values of $44.1 million at September 30, 2015.

Investments (Other Investments)

Investments (Other Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 842,446	$ 541,454
Commitments under investment fund classified within other investments	59,763	70,542
Prohibited amount under redemption requests over the next 12 months	196,930	85,244
Alternative funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	747,198	485,944
Commitments under investment fund classified within other investments	59,763	70,542
Prohibited amount under redemption requests over the next 12 months	196,930	85,244
Hedge funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	641,089	411,280
Commitments under investment fund classified within other investments	0	0
Prohibited amount under redemption requests over the next 12 months	89,387	10,580
Private investment funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	82,532	74,664
Commitments under investment fund classified within other investments	59,763	70,542
Prohibited amount under redemption requests over the next 12 months	82,532	74,664
Other investment funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	23,577
Commitments under investment fund classified within other investments	0
Prohibited amount under redemption requests over the next 12 months	25,011
Specialty funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	95,248	55,510
Commitments under investment fund classified within other investments	0	0
Prohibited amount under redemption requests over the next 12 months	0	0
High yield loan funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	95,248	55,510
Commitments under investment fund classified within other investments	0	0
Prohibited amount under redemption requests over the next 12 months	$ 0	$ 0

Investments (Other Investments

Investments (Other Investments Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Other investments, invested amount	$ 652,400	$ 387,200
Other investments, market value	842,446	541,454
Alternative funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 747,198	485,944
Hedge funds
Schedule of Equity Method Investments [Line Items]
Estimated liquidation, percentage in next 12 months	86.10%
Other investments, market value	$ 641,089	411,280
Hedge funds | Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated notice period, in days	90 days
Hedge funds | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated notice period, in days	30 days
Private investment funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 82,532	74,664
Private investment funds | Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated remaining liquidation period in years	10 years
Private investment funds | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated remaining liquidation period in years	5 years
Specialty funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 95,248	55,510
High yield loan funds
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 95,248	$ 55,510
High yield loan funds | Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated notice period, in days	90 days
High yield loan funds | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated notice period, in days	30 days

Investments (Net Realized and U

Investments (Net Realized and Unrealized Gains) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Investments [Abstract]
Gross realized gains on investment sales		$ 20,107	$ 10,683	$ 57,420	$ 28,317
Gross realized losses on investment sales		(8,236)	(1,475)	(18,190)	(12,778)
Net unrealized losses on trading securities		(5,037)	0	(5,037)	0
Change in fair value of derivative financial instruments	[1]	(1,805)	580	(1,295)	2,532
Net realized and unrealized gains		$ 5,029	$ 9,788	$ 32,898	$ 18,071
[1]	For additional information on the Company's derivative financial instruments, see Note 7, Derivatives.

Investments (Amortized Cost, Fa

Investments (Amortized Cost, Fair Value, Gross Unrealized Gains And Losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2015		Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	$ 4,615,296		$ 5,032,506
Fixed income investments, fair value	4,656,145		5,092,581
Equity securities, cost	535,764		303,922
Equity securities, fair value	496,035		331,368
U.S. government and agencies securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	590,216		582,970
Fixed income investments, gross unrealized gains	8,675		6,471
Fixed income investments, gross unrealized losses	(1,358)		(2,030)
Fixed income investments, fair value	597,533		587,411
U.S. state and municipal securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	24,157		39,340
Fixed income investments, gross unrealized gains	262		191
Fixed income investments, gross unrealized losses	(108)		(118)
Fixed income investments, fair value	24,311		39,413
Foreign government securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	108,099		239,217
Fixed income investments, gross unrealized gains	1,073		2,983
Fixed income investments, gross unrealized losses	(522)		(1,664)
Fixed income investments, fair value	108,650		240,536
Government guaranteed corporate securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	25,416		47,436
Fixed income investments, gross unrealized gains	392		675
Fixed income investments, gross unrealized losses	(11)		(9)
Fixed income investments, fair value	25,797		48,102
Corporate securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	1,316,038		1,354,370
Fixed income investments, gross unrealized gains	10,344		12,742
Fixed income investments, gross unrealized losses	(6,844)		(5,650)
Fixed income investments, fair value	1,319,538		1,361,462
Residential mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	1,080,411		1,149,536
Fixed income investments, gross unrealized gains	23,611		27,542
Fixed income investments, gross unrealized losses	(2,519)		(2,072)
Fixed income investments, fair value	1,101,503		1,175,006
Commercial mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	737,543		960,598
Fixed income investments, gross unrealized gains	10,676		21,374
Fixed income investments, gross unrealized losses	(3,353)		(2,553)
Fixed income investments, fair value	744,866		979,419
Collateralized loan and debt obligations
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	316,161	[1]	247,510	[2]
Fixed income investments, gross unrealized gains	1,214	[1]	1,449	[2]
Fixed income investments, gross unrealized losses	(1,476)	[1]	(948)	[2]
Fixed income investments, fair value	315,899	[1]	248,011	[2]
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	417,255		411,529
Fixed income investments, gross unrealized gains	1,792		2,265
Fixed income investments, gross unrealized losses	(999)		(573)
Fixed income investments, fair value	418,048		413,221
Fixed maturity investments
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	4,615,296		5,032,506
Fixed income investments, gross unrealized gains	58,039		75,692
Fixed income investments, gross unrealized losses	(17,190)		(15,617)
Fixed income investments, fair value	4,656,145		5,092,581
Short-term investments
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	16,356		9,015
Fixed income investments, gross unrealized gains	0		0
Fixed income investments, gross unrealized losses	0		(1)
Fixed income investments, fair value	16,356		9,014
Fixed income investments
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	4,631,652		5,041,521
Fixed income investments, gross unrealized gains	58,039		75,692
Fixed income investments, gross unrealized losses	(17,190)		(15,618)
Fixed income investments, fair value	4,672,501		5,101,595
Equity investments
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	407,206		176,167
Equity securities, gross unrealized gains	2,709		29,660
Equity securities, gross unrealized losses	(40,460)		(3,292)
Equity securities, fair value	369,455		202,535
Emerging market debt funds
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	61,874		60,826
Equity securities, gross unrealized gains	0		0
Equity securities, gross unrealized losses	(3,021)		(676)
Equity securities, fair value	58,853		60,150
Convertible funds
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	46,331		46,331
Equity securities, gross unrealized gains	0		0
Equity securities, gross unrealized losses	(477)		(220)
Equity securities, fair value	45,854		46,111
Preferred equity investments
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	15,427		13,858
Equity securities, gross unrealized gains	1,847		2,022
Equity securities, gross unrealized losses	(326)		(44)
Equity securities, fair value	16,948		15,836
Short-term fixed income fund
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	4,926		6,740
Equity securities, gross unrealized gains	0		0
Equity securities, gross unrealized losses	(1)		(4)
Equity securities, fair value	4,925		6,736
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	535,764		303,922
Equity securities, gross unrealized gains	4,556		31,682
Equity securities, gross unrealized losses	(44,285)		(4,236)
Equity securities, fair value	496,035		331,368
Collateralized debt obligations
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, fair value	$ 13,200		$ 15,200
[1]	Balances include amounts related to collateralized debt obligations held with total fair values of $13.2 million.
[2]	Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million.

Investments (Available For Sale

Investments (Available For Sale Securities In An Unrealized Loss Position) (Details) - USD ($) $ in Thousands		Sep. 30, 2015		Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, 12 months or greater		$ (5,500)	[1]	$ (7,100)	[2]
Unrealized losses		(61,500)	[1]	(19,900)	[2]
U.S. government and agencies securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(438)	[1]	(481)	[2]
Fair value, less than 12 months		71,512		155,350
Unrealized losses, 12 months or greater		(920)	[1]	(1,549)	[2]
Fair value, 12 months or greater		21,859		45,993
Unrealized losses		(1,358)	[1]	(2,030)	[2]
Fair value		93,371		201,343
U.S. state and municipal securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(44)	[1]	(47)	[2]
Fair value, less than 12 months		2,311		3,295
Unrealized losses, 12 months or greater		(64)	[1]	(71)	[2]
Fair value, 12 months or greater		708		6,841
Unrealized losses		(108)	[1]	(118)	[2]
Fair value		3,019		10,136
Foreign government securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(442)	[1]	(1,378)	[2]
Fair value, less than 12 months		24,977		37,904
Unrealized losses, 12 months or greater		(80)	[1]	(286)	[2]
Fair value, 12 months or greater		4,558		4,306
Unrealized losses		(522)	[1]	(1,664)	[2]
Fair value		29,535		42,210
Government guaranteed corporate securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(11)	[1]	(9)	[2]
Fair value, less than 12 months		1,737		4,598
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(11)	[1]	(9)	[2]
Fair value		1,737		4,598
Corporate securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(5,687)	[1]	(4,023)	[2]
Fair value, less than 12 months		493,115		533,139
Unrealized losses, 12 months or greater		(1,157)	[1]	(1,627)	[2]
Fair value, 12 months or greater		44,942		84,278
Unrealized losses		(6,844)	[1]	(5,650)	[2]
Fair value		538,057		617,417
Residential mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(1,300)	[1]	(260)	[2]
Fair value, less than 12 months		174,347		62,832
Unrealized losses, 12 months or greater		(1,219)	[1]	(1,812)	[2]
Fair value, 12 months or greater		75,619		108,899
Unrealized losses		(2,519)	[1]	(2,072)	[2]
Fair value		249,966		171,731
Commercial mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(1,853)	[1]	(1,068)	[2]
Fair value, less than 12 months		214,560		180,222
Unrealized losses, 12 months or greater		(1,500)	[1]	(1,485)	[2]
Fair value, 12 months or greater		45,802		78,412
Unrealized losses		(3,353)	[1]	(2,553)	[2]
Fair value		260,362		258,634
Collateralized loan and debt obligations
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(1,075)	[1]	(876)	[2]
Fair value, less than 12 months		193,044		176,439
Unrealized losses, 12 months or greater		(401)	[1]	(72)	[2]
Fair value, 12 months or greater		44,551		6,491
Unrealized losses		(1,476)	[1]	(948)	[2]
Fair value		237,595		182,930
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(807)	[1]	(415)	[2]
Fair value, less than 12 months		162,488		199,205
Unrealized losses, 12 months or greater		(192)	[1]	(158)	[2]
Fair value, 12 months or greater		17,011		19,095
Unrealized losses		(999)	[1]	(573)	[2]
Fair value		179,499		218,300
Fixed maturity investments
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months	[2]			(8,557)
Fair value, less than 12 months				1,352,984
Unrealized losses, 12 months or greater	[2]			(7,060)
Fair value, 12 months or greater				354,315
Unrealized losses	[2]			(15,617)
Fair value				1,707,299
Short-term investments
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months	[2]			(1)
Fair value, less than 12 months				1,953
Unrealized losses, 12 months or greater	[2]			0
Fair value, 12 months or greater				0
Unrealized losses	[2]			(1)
Fair value				1,953
Fixed income investments
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(11,657)	[1]	(8,558)	[2]
Fair value, less than 12 months		1,338,091		1,354,937
Unrealized losses, 12 months or greater		(5,533)	[1]	(7,060)	[2]
Fair value, 12 months or greater		255,050		354,315
Unrealized losses		(17,190)	[1]	(15,618)	[2]
Fair value		1,593,141		1,709,252
Equity investments
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(40,460)	[1]	(3,292)	[2]
Fair value, less than 12 months		321,413		53,591
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(40,460)	[1]	(3,292)	[2]
Fair value		321,413		53,591
Emerging market debt funds
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(3,021)	[1]	(676)	[2]
Fair value, less than 12 months		58,853		60,150
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(3,021)	[1]	(676)	[2]
Fair value		58,853		60,150
Convertible funds
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(477)	[1]	(220)	[2]
Fair value, less than 12 months		45,854		46,111
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(477)	[1]	(220)	[2]
Fair value		45,854		46,111
Preferred equity investments
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(326)	[1]	(44)	[2]
Fair value, less than 12 months		9,027		4,449
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(326)	[1]	(44)	[2]
Fair value		9,027		4,449
Short-term fixed income fund
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(1)	[1]	(4)	[2]
Fair value, less than 12 months		4,924		6,736
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(1)	[1]	(4)	[2]
Fair value		4,924		6,736
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(44,285)	[1]	(4,236)	[2]
Fair value, less than 12 months		440,071		171,037
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(44,285)	[1]	(4,236)	[2]
Fair value		$ 440,071		$ 171,037
[1]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at September 30, 2015.
[2]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive (loss) income at December 31, 2014.

Investments Investments (Noncon

Investments Investments (Noncontrolling Interests Rollforward) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jul. 31, 2015
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Non-controlling interests acquired July 31, 2015	$ 259,474		$ 0		$ 258,529
Net income attributable to non-controlling interests	2,707	$ 0	2,707	$ 0
Non-controlling interests - ending balance			$ 0
Blue Capital Reinsurance Holdings [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net income attributable to non-controlling interests	1,886
Net third-party investments in BCRH	(7)
Dividends declared by BCRH attributable to non-controlling interests	$ (1,755)
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	33.30%
Blue Capital Global Reinsurance Fund [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net income attributable to non-controlling interests	$ 821
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	25.10%
Blue Capital Global Reinsurance Fund [Member] | Maximum [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	50.00%

Fair Value Measurement (Narrati

Fair Value Measurement (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers in to Level 3	$ 361,017,000	$ 2,198,000	$ 362,987,000	$ 7,201,000
Transfers out of Level 3	0	(4,961,000)	(9,176,000)	(6,813,000)
Net impairment losses recognized in earnings	38,000	102,000	1,111,000	411,000
Other Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers in to Level 3	232,137,000	0	232,137,000	0
Transfers out of Level 3	0	0	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers in to Level 3	128,900,000		130,900,000
Transfers out of Level 3	$ 0		$ (9,200,000)
Percentage of level 3 assets	12.70%		12.70%		9.50%
Net impairment losses recognized in earnings	$ 0	$ 0	$ 0	$ 0

Fair Value Measurement (Schedul

Fair Value Measurement (Schedule Of Fixed Maturity Investments, Equity Securities, Short-term Investments, Other Investments, Derivative Instruments And Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Assets
Short-term investments	$ 364,938	$ 9,014
Other investments	842,446	541,454
Other assets (see Note 7)	80,395	99,504
Total assets	7,814,139	6,073,921
Liabilities
Other liabilities (see Note 7)	53,534	54,338
Debt	968,248	623,740
Total liabilities	1,021,782	678,078
Fair Value, Inputs, Level 1 [Member]
Assets
Short-term investments	0	0
Other investments	0	0
Other assets (see Note 7)	0	0
Total assets	292,702	250,320
Liabilities
Other liabilities (see Note 7)	0	0
Debt	0	0
Total liabilities	0	0
Fair Value, Inputs, Level 2 [Member]
Assets
Short-term investments	364,938	9,014
Other investments	0	0
Other assets (see Note 7)	60,218	73,889
Total assets	6,525,438	5,244,242
Liabilities
Other liabilities (see Note 7)	33,809	18,972
Debt	968,248	623,740
Total liabilities	1,002,057	642,712
Fair Value, Inputs, Level 3 [Member]
Assets
Short-term investments	0	0
Other investments	842,446	541,454
Other assets (see Note 7)	20,177	25,615
Total assets	995,999	579,359
Liabilities
Other liabilities (see Note 7)	19,725	35,366
Debt	0	0
Total liabilities	19,725	35,366
U.S. government and agencies securities
Assets
Fixed maturity investments	806,143	587,411
U.S. government and agencies securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	48,589	105,121
U.S. government and agencies securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	757,554	482,290
U.S. government and agencies securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0	0
U.S. state and municipal securities
Assets
Fixed maturity investments	28,936	39,413
U.S. state and municipal securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
U.S. state and municipal securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	28,936	39,413
U.S. state and municipal securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0	0
Foreign government securities
Assets
Fixed maturity investments	157,212	240,536
Foreign government securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
Foreign government securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	157,212	240,536
Foreign government securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0	0
Government guaranteed corporate securities
Assets
Fixed maturity investments	65,930	48,102
Government guaranteed corporate securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
Government guaranteed corporate securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	65,930	48,102
Government guaranteed corporate securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0	0
Corporate securities
Assets
Fixed maturity investments	1,878,766	1,361,462
Corporate securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
Corporate securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	1,750,877	1,358,960
Corporate securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	127,889	2,502
Residential mortgage-backed securities
Assets
Fixed maturity investments	1,222,805	1,175,006
Residential mortgage-backed securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
Residential mortgage-backed securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	1,222,680	1,174,997
Residential mortgage-backed securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	125	9
Commercial mortgage-backed securities
Assets
Fixed maturity investments	837,772	979,419
Commercial mortgage-backed securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
Commercial mortgage-backed securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	835,321	974,602
Commercial mortgage-backed securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	2,451	4,817
Collateralized loan and debt obligations
Assets
Fixed maturity investments	418,875	248,011
Collateralized loan and debt obligations | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
Collateralized loan and debt obligations | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	415,964	246,042
Collateralized loan and debt obligations | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	2,911	1,969
Asset-backed securities
Assets
Fixed maturity investments	611,736	413,221
Asset-backed securities | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0	0
Asset-backed securities | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	611,736	410,228
Asset-backed securities | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0	2,993
Fixed maturity investments
Assets
Fixed maturity investments	6,028,175	5,092,581
Fixed maturity investments | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	48,589	105,121
Fixed maturity investments | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	5,846,210	4,975,170
Fixed maturity investments | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	133,376	12,290
Equity investments
Assets
Equity securities	369,525	202,535
Equity investments | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	239,188	138,463
Equity investments | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	130,337	64,072
Equity investments | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0	0
Emerging market debt funds
Assets
Equity securities	58,853	60,150
Emerging market debt funds | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	0	0
Emerging market debt funds | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	58,853	60,150
Emerging market debt funds | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0	0
Convertible funds
Assets
Equity securities	45,854	46,111
Convertible funds | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	0	0
Convertible funds | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	45,854	46,111
Convertible funds | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0	0
Preferred equity investments
Assets
Equity securities	19,028	15,836
Preferred equity investments | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	0	0
Preferred equity investments | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	19,028	15,836
Preferred equity investments | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0	0
Short-term fixed income fund
Assets
Equity securities	4,925	6,736
Short-term fixed income fund | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	4,925	6,736
Short-term fixed income fund | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	0	0
Short-term fixed income fund | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0	0
Equity securities
Assets
Equity securities	498,185	331,368
Equity securities | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	244,113	145,199
Equity securities | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	254,072	186,169
Equity securities | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	$ 0	$ 0

Fair Value Measurement (Quantit

Fair Value Measurement (Quantitative Information Used As Level 3 Inputs) (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2015USD ($)	Dec. 31, 2014USD ($)
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Net weather and energy related derivative assets and liabilities	$ 26,861,000	$ 45,166,000
Derivatives recorded in other assets, fair value	80,395,000	99,504,000
Derivatives recorded in other liabilities, fair value	53,534,000	54,338,000
Energy Related Derivative [Member]
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Derivatives recorded in other assets, fair value	20,177,000	25,615,000
Derivatives recorded in other liabilities, fair value	19,725,000	35,366,000
Simulation Valuation Technique [Member] | Energy Related Derivative [Member]
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Net weather and energy related derivative assets and liabilities	452,000	(9,751,000)
Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Derivatives recorded in other assets, fair value	20,177,000	25,615,000
Derivatives recorded in other liabilities, fair value	$ 19,725,000	$ 35,366,000
Fair Value, Inputs, Level 3 [Member] | Simulation Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Correlation	1	1
Weather curve	$ 10,600,000	$ 2,500,000
Commodity curve	$ 13,000	$ 13
Fair Value, Inputs, Level 3 [Member] | Simulation Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Correlation	0	0
Weather curve	$ 2,200,000	$ (828,000)
Commodity curve	$ 0	$ 0

Fair Value Measurement (Reconci

Fair Value Measurement (Reconciliation Of The Beginning And Ending Balances For Fixed Maturity Investments, Other Investments, Other Assets and Other Liabilities Measured At Fair Value On A Recurring Basis Using Level 3 Inputs) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	$ 652,266	$ 669,149	$ 579,359	$ 638,844
Total equity income and realized gains included in earnings	10,031	10,922	45,162	46,447
Total equity losses and losses included in earnings	(22,487)	(12,704)	(41,558)	(23,876)
Total income included in other underwriting income (loss)	1,589	3,180	7,184	18,396
Total loss included in other underwriting income (loss)	(11,794)	(5,235)	(24,788)	(23,845)
Change in unrealized gains included in other comprehensive (loss) income	85	245	109	445
Change in unrealized losses included in other comprehensive (loss) income	(35)	(104)	(228)	(255)
Purchases	13,366	28,533	116,345	55,074
Issues	5,441	7,331	17,774	10,912
Sales	(13,480)	(14,914)	(50,313)	(35,657)
Settlements	0	(2,947)	(6,858)	(6,180)
Transfers in to Level 3	361,017	2,198	362,987	7,201
Transfers out of Level 3	0	(4,961)	(9,176)	(6,813)
Level 3, end of period	995,999	680,693	995,999	680,693
Fixed Maturity Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	4,707	9,515	12,290	7,328
Total equity income and realized gains included in earnings	0	9	113	62
Total equity losses and losses included in earnings	(24)	(6)	(35)	(32)
Total income included in other underwriting income (loss)	0	0	0	0
Total loss included in other underwriting income (loss)	0	0	0	0
Change in unrealized gains included in other comprehensive (loss) income	85	245	109	445
Change in unrealized losses included in other comprehensive (loss) income	(35)	(104)	(228)	(255)
Purchases	0	842	0	842
Issues	0	0	0	0
Sales	(237)	(545)	(547)	(1,585)
Settlements	0	0	0	0
Transfers in to Level 3	128,880	2,198	130,850	7,201
Transfers out of Level 3	0	(4,961)	(9,176)	(6,813)
Level 3, end of period	133,376	7,193	133,376	7,193
Other Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	623,868	648,642	541,454	617,478
Total equity income and realized gains included in earnings	10,031	10,913	45,049	46,385
Total equity losses and losses included in earnings	(22,463)	(12,698)	(41,523)	(23,844)
Total income included in other underwriting income (loss)	0	0	0	0
Total loss included in other underwriting income (loss)	0	0	0	0
Change in unrealized gains included in other comprehensive (loss) income	0	0	0	0
Change in unrealized losses included in other comprehensive (loss) income	0	0	0	0
Purchases	12,116	26,190	115,095	52,731
Issues	0	0	0	0
Sales	(13,243)	(14,369)	(49,766)	(34,072)
Settlements	0	0	0	0
Transfers in to Level 3	232,137	0	232,137	0
Transfers out of Level 3	0	0	0	0
Level 3, end of period	842,446	658,678	842,446	658,678
Other Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	23,691	10,992	25,615	14,038
Total equity income and realized gains included in earnings	0	0	0	0
Total equity losses and losses included in earnings	0	0	0	0
Total income included in other underwriting income (loss)	1,589	3,180	7,184	18,396
Total loss included in other underwriting income (loss)	(11,794)	(5,235)	(24,788)	(23,845)
Change in unrealized gains included in other comprehensive (loss) income	0	0	0	0
Change in unrealized losses included in other comprehensive (loss) income	0	0	0	0
Purchases	1,250	1,501	1,250	1,501
Issues	5,441	7,331	17,774	10,912
Sales	0	0	0	0
Settlements	0	(2,947)	(6,858)	(6,180)
Transfers in to Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Level 3, end of period	20,177	14,822	20,177	14,822
Other Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	(22,184)	(10,284)	(35,366)	(19,569)
Total equity income and realized gains included in earnings	0	0	0	0
Total equity losses and losses included in earnings	0	0	0	0
Total income included in other underwriting income (loss)	14,745	4,794	35,610	24,842
Total loss included in other underwriting income (loss)	(2,552)	(3,719)	(9,772)	(20,672)
Change in unrealized gains included in other comprehensive (loss) income	0	0	0	0
Change in unrealized losses included in other comprehensive (loss) income	0	0	0	0
Purchases	(737)	(751)	(737)	(751)
Issues	(9,058)	(10,917)	(27,806)	(18,080)
Sales	0	0	0	0
Settlements	61	4,961	18,346	18,314
Transfers in to Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Level 3, end of period	$ (19,725)	$ (15,916)	$ (19,725)	$ (15,916)

Earnings Per Share (Schedule Of

Earnings Per Share (Schedule Of Computing Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Net income available to Endurance Holdings common and participating common shareholders		$ 43,635	$ 68,046	$ 219,944	$ 239,313
Less amount allocated to participating common shareholders	[1]	(1,251)	(1,930)	(6,442)	(6,907)
Net income allocated to Endurance Holdings common shareholders		$ 42,384	$ 66,116	$ 213,502	$ 232,406
Weighted average shares - basic		57,923,044	43,464,790	48,453,368	43,332,461
Weighted average shares - diluted		58,046,148	43,510,415	48,592,101	43,355,792
Basic earnings per Endurance Holdings common share		$ 0.73	$ 1.52	$ 4.41	$ 5.36
Diluted earnings per Endurance Holdings common share		$ 0.73	$ 1.52	$ 4.39	$ 5.36
Employee Stock Option [Member]
Share equivalents		111,760	45,625	137,366	23,237
Restricted Stock [Member]
Share equivalents		11,344	0	1,367	94
[1]	Represents earnings attributable to holders of unvested restricted shares and restricted share units issued under the Company's equity compensation plan that are considered participating. In periods of loss, no losses are allocated to participating common shareholders (unvested restricted shares and restricted share units).

Earnings Per Share (Schedule 52

Earnings Per Share (Schedule Of Dividends Declared) (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Dividends Declared [Line Items]
Dividends declared per common share	$ 0.35	$ 0.34	$ 1.05	$ 1.02
Series A Preferred Stock [Member]
Dividends Declared [Line Items]
Dividends declared per preferred share	0.484375	0.484375	1.453125	1.453125
Series B Preferred Stock [Member]
Dividends Declared [Line Items]
Dividends declared per preferred share	$ 0.468750	$ 0.468750	$ 1.406250	$ 1.406250

Accumulated Other Comprehensi53

Accumulated Other Comprehensive Income (Schedule Of Changes In Accumulated Other Comprehensive Income By Component) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning balance		$ 36,965	$ 136,038	$ 76,706	$ 62,731
Other comprehensive (loss) income before reclassifications		(33,883)	(45,850)	(48,115)	33,714
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	(11,626)	(8,889)	(37,135)	(15,146)
Other comprehensive (loss) income		(45,509)	(54,739)	(85,250)	18,568
Ending balance		(8,544)	81,299	(8,544)	81,299
Gains and losses on cash flow hedges [Member]
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning balance		(1,722)	(1,810)	(1,766)	(1,855)
Other comprehensive (loss) income before reclassifications		0	0	0	0
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	22	22	66	67
Other comprehensive (loss) income		22	22	66	67
Ending balance		(1,700)	(1,788)	(1,700)	(1,788)
Unrealized gains on available for sale securities [Member]
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning balance		43,610	106,989	86,100	45,950
Other comprehensive (loss) income before reclassifications		(18,258)	(25,446)	(35,195)	41,895
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	(11,648)	(8,911)	(37,201)	(15,213)
Other comprehensive (loss) income		(29,906)	(34,357)	(72,396)	26,682
Ending balance		13,704	72,632	13,704	72,632
Foreign currency translation adjustments [Member]
Accumulated Other Comprehensive (Loss) Income [Line Items]
Beginning balance		(4,923)	30,859	(7,628)	18,636
Other comprehensive (loss) income before reclassifications		(15,625)	(20,404)	(12,920)	(8,181)
Amounts reclassified from accumulated other comprehensive (loss) income	[1]	0	0	0	0
Other comprehensive (loss) income		(15,625)	(20,404)	(12,920)	(8,181)
Ending balance		$ (20,548)	$ 10,455	$ (20,548)	$ 10,455
[1]	All amounts are net of tax.

Accumulated Other Comprehensi54

Accumulated Other Comprehensive (Loss) Income (Schedule Of Reclassifications Out Of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive (Loss) Income [Line Items]
Interest expense	$ 12,324	$ 13,127	$ 30,445	$ 31,910
Net realized and unrealized gains	(5,029)	(9,788)	(32,898)	(18,071)
Net impairment losses recognized in earnings	38	102	1,111	411
Total before income taxes	(56,940)	(71,952)	(254,927)	(260,143)
Income tax expense (benefit)	2,410	(4,282)	7,712	(3,734)
Total net of income taxes	(51,823)	(76,234)	(244,508)	(263,877)
Gains and losses on cash flow hedges [Member] | Reclassification out of Accumulated Other Comprehensive (Loss) Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive (Loss) Income [Line Items]
Interest expense	22	22	66	67
Total before income taxes	22	22	66	67
Income tax expense (benefit)	0	0	0	0
Total net of income taxes	22	22	66	67
Unrealized gains on available for sale securities [Member] | Reclassification out of Accumulated Other Comprehensive (Loss) Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive (Loss) Income [Line Items]
Net realized and unrealized gains	(11,871)	(9,208)	(39,230)	(15,539)
Net impairment losses recognized in earnings	38	102	1,111	411
Total before income taxes	(11,833)	(9,106)	(38,119)	(15,128)
Income tax expense (benefit)	185	195	918	(85)
Total net of income taxes	$ (11,648)	$ (8,911)	$ (37,201)	$ (15,213)

Derivatives (Schedule Of Deriva

Derivatives (Schedule Of Derivative Fair Value And Notional Amount) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	$ 80,395	$ 99,504
Derivatives recorded in other liabilities, fair value	53,534	54,338
Net derivative asset, fair value	$ 26,861	45,166
Term of LIBOR swap	5 years
Derivative assets traded under master netting agreements	$ 80,400	99,500
Derivative liabilities traded under master netting agreements	$ 53,500	54,300
Maximum [Member]
Derivatives, Fair Value [Line Items]
Original term of credit default swap, in years	5 years
Foreign Exchange Forward [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	$ 663	651
Derivatives recorded in other liabilities, fair value	418	123
Derivatives recorded in other assets, notional principal amount	49,845	42,694
Derivatives recorded in other liabilities, notional principal amount	24,832	20,945
Credit Default Swap [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	17	0
Derivatives recorded in other liabilities, fair value	322	0
Derivatives recorded in other assets, notional principal amount	4,290	0
Derivatives recorded in other liabilities, notional principal amount	6,600	0
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	156	0
Derivatives recorded in other liabilities, fair value	198	20
Derivatives recorded in other assets, notional principal amount	4,000	0
Derivatives recorded in other liabilities, notional principal amount	40,100	12,549
Interest Rate Future [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	8	7
Derivatives recorded in other liabilities, fair value	3	0
Derivatives recorded in other assets, notional principal amount	54,659	7,595
Derivatives recorded in other liabilities, notional principal amount	9,762	0
Interest Rate Swaption [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other liabilities, fair value	0	9
Derivatives recorded in other liabilities, notional principal amount	0	13,100
Industry Loss Warranty [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	536	0
Derivatives recorded in other liabilities, fair value	1,120	0
Derivatives recorded in other assets, notional principal amount	12,500	0
Derivatives recorded in other liabilities, notional principal amount	19,500	0
LIBOR Swap [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other liabilities, fair value	738	0
Derivatives recorded in other liabilities, notional principal amount	$ 100,000	0
Fixed interest rate percentage	4.905%
Term of LIBOR swap	5 years
TBA [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	$ 58,838	73,231
Derivatives recorded in other liabilities, fair value	31,010	18,820
Derivatives recorded in other assets, notional principal amount	55,000	70,000
Derivatives recorded in other liabilities, notional principal amount	29,000	18,000
Energy and weather contracts [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	20,177	25,615
Derivatives recorded in other liabilities, fair value	19,725	35,366
Derivatives recorded in other assets, notional principal amount	70,143	81,624
Derivatives recorded in other liabilities, notional principal amount	$ 112,435	$ 135,050

Derivatives (Schedule Of Deri56

Derivatives (Schedule Of Derivative Gain) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	$ (1,805)	$ 580	$ (1,295)	$ 2,532
Total gains from derivatives	338	3,578	8,016	4,833
Foreign Exchange Forward [Member]
Derivative [Line Items]
Derivatives included in net foreign exchange losses from foreign exchange forward contracts	155	1,214	1,281	815
Interest Rate Future [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(78)	0	17	136
Credit Default Swap [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(143)	6	(134)	20
Interest Rate Swap [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(705)	384	(940)	(698)
Interest Rate Swaption [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	28	(3)	56	425
Industry Loss Warranty [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(652)	0	(652)	0
LIBOR Swap [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(173)	0	(173)	0
TBA [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(82)	193	531	2,649
Energy and weather contracts [Member]
Derivative [Line Items]
Derivatives included in other underwriting income (loss) from energy and weather contracts	$ 1,988	$ 1,784	$ 8,030	$ 1,486

Stock-Based Employee Compensa57

Stock-Based Employee Compensation And Other Stock Plans (Narrative) (Details) - USD ($)	Jul. 31, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised		$ 9,500,000		$ 9,500,000	$ 300,000
Proceeds from stock options exercised		$ 23,100,000		$ 23,100,000	$ 500,000
Restricted shares and RSUs, grants in period		14,703	39,080	519,055	472,497
RSUs assumed		841,926		841,926
Restricted shares and RSUs weighted average grant date fair value		$ 59,400,000	$ 2,100,000	$ 89,400,000	$ 24,800,000
Aggregate fair value of restricted shares and RSUs vested		23,000,000	200,000	44,700,000	18,700,000
Exchange ratio	0.472
Expenses related to employee stock purchase plan		$ 76,000	$ 62,000	$ 220,000	$ 172,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting rate				20.00%
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate of restricted shares on death disability or change of control, percentage				50.00%
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for employee awards				4 years
Restricted share awards to non-employee directors, vesting period				12 months
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for employee awards				4 years
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life of stock options				10 years
Number of options granted		0	0	0	0
Number of options expired		0	0	0	0
Number of options vested		0	0	160,000	160,000
Number of options exercised		480,000	0	480,000	15,000
Compensation costs recognized in earnings		$ 300,000	$ 600,000	$ 1,300,000	$ 2,500,000
Compensation costs not yet recognized - stock options		1,300,000	3,200,000	1,300,000	3,200,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs recognized in earnings		28,100,000	5,700,000	45,000,000	21,500,000
Compensation costs not yet recognized - restricted stock		32,000,000	$ 27,700,000	32,000,000	$ 27,700,000
Restricted Stock [Member] | Montpelier [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs recognized in earnings		$ 20,400,000		$ 20,400,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for employee awards				3 years

Stock-Based Employee Compensa58

Stock-Based Employee Compensation And Other Stock Plans (Restricted Share And Restricted Share Unit Activity) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, beginning of period	1,290,894
Granted and assumed	1,360,981
Settled	(776,614)
Forfeited	(17,701)
Unvested, end of period	1,857,560
Number of Shares/Units, Outstanding, end of period	1,290,894	1,857,560
Aggregate Intrinsic Value, Outstanding, end of period		$ 113,367

Segment Reporting (Summary Of T

Segment Reporting (Summary Of The Segment Revenues, Results, Goodwill And Reserve For Losses And Loss Expenses) (Details) - USD ($) $ in Thousands		2 Months Ended	3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Gross premiums written			$ 642,597	$ 626,110	$ 2,805,213	$ 2,473,050
Ceded premiums written			(305,907)	(236,004)	(1,144,486)	(772,812)
Net premiums written			336,690	390,106	1,660,727	1,700,238
Net premiums earned			557,003	514,895	1,404,997	1,392,699
Other underwriting income (loss)			227	2,123	4,022	(3,939)
Total revenue			557,230	517,018	1,409,019	1,388,760
Net losses and loss expenses			263,993	290,269	675,051	726,361
Acquisition expenses			90,457	93,392	257,521	244,150
General and administrative expenses			60,793	68,946	170,648	186,759
Total expenses			415,243	452,607	1,103,220	1,157,270
Underwriting income			141,987	64,411	305,799	231,490
Net investment income			16,533	25,357	90,646	105,649
Corporate expenses			(74,308)	(11,969)	(99,210)	(53,817)
Net foreign exchange losses			(8,621)	(783)	(29,154)	(4,066)
Net realized and unrealized gains			5,029	9,788	32,898	18,071
Net impairment losses recognized in earnings			(38)	(102)	(1,111)	(411)
Amortization of intangibles		$ (9,734)	(11,318)	(1,623)	(14,496)	(4,863)
Interest expense			(12,324)	(13,127)	(30,445)	(31,910)
Income before income taxes			$ 56,940	$ 71,952	$ 254,927	$ 260,143
Net loss ratio			47.40%	56.40%	48.10%	52.20%
Acquisition expense ratio			16.20%	18.10%	18.30%	17.50%
General and administrative expense ratio	[1]		24.30%	15.70%	19.20%	17.30%
Combined ratio			87.90%	90.20%	85.60%	87.00%
Reserve for losses and loss expenses		4,489,836	$ 4,489,836	$ 3,897,483	$ 4,489,836	$ 3,897,483	$ 3,846,859
Goodwill		177,426	177,426	91,326	177,426	91,326	$ 91,238
Insurance [Member]
Segment Reporting Information [Line Items]
Gross premiums written			448,563	420,343	1,653,647	1,394,145
Ceded premiums written			(273,626)	(222,704)	(984,372)	(674,441)
Net premiums written			174,937	197,639	669,275	719,704
Net premiums earned			234,143	253,583	571,467	616,167
Other underwriting income (loss)			0	0	0	0
Total revenue			234,143	253,583	571,467	616,167
Net losses and loss expenses			139,141	196,677	359,136	434,777
Acquisition expenses			24,375	20,170	57,960	47,559
General and administrative expenses			31,880	40,401	89,289	113,069
Total expenses			195,396	257,248	506,385	595,405
Underwriting income			$ 38,747	$ (3,665)	$ 65,082	$ 20,762
Net loss ratio			59.50%	77.50%	62.90%	70.60%
Acquisition expense ratio			10.40%	8.00%	10.10%	7.70%
General and administrative expense ratio			13.60%	15.90%	15.60%	18.30%
Combined ratio			83.50%	101.40%	88.60%	96.60%
Reserve for losses and loss expenses		2,442,821	$ 2,442,821	$ 2,134,985	$ 2,442,821	$ 2,134,985
Goodwill		85,179	85,179	47,925	85,179	47,925
Reinsurance [Member]
Segment Reporting Information [Line Items]
Gross premiums written			194,034	205,767	1,151,566	1,078,905
Ceded premiums written			(32,281)	(13,300)	(160,114)	(98,371)
Net premiums written			161,753	192,467	991,452	980,534
Net premiums earned			322,860	261,312	833,530	776,532
Other underwriting income (loss)			227	2,123	4,022	(3,939)
Total revenue			323,087	263,435	837,552	772,593
Net losses and loss expenses			124,852	93,592	315,915	291,584
Acquisition expenses			66,082	73,222	199,561	196,591
General and administrative expenses			28,913	28,545	81,359	73,690
Total expenses			219,847	195,359	596,835	561,865
Underwriting income			$ 103,240	$ 68,076	$ 240,717	$ 210,728
Net loss ratio			38.60%	35.80%	37.90%	37.60%
Acquisition expense ratio			20.50%	28.00%	23.90%	25.30%
General and administrative expense ratio			9.00%	11.00%	9.80%	9.50%
Combined ratio			68.10%	74.80%	71.60%	72.40%
Reserve for losses and loss expenses		2,047,015	$ 2,047,015	$ 1,762,498	$ 2,047,015	$ 1,762,498
Goodwill		$ 92,247	$ 92,247	$ 43,401	$ 92,247	$ 43,401
[1]	Total general and administrative expense ratio includes general and administrative expenses and corporate expenses.

Segment Reporting (Schedule Of

Segment Reporting (Schedule Of Gross And Net Premiums Written By Line Of Business) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenue from External Customer [Line Items]
Gross premiums written	$ 642,597	$ 626,110	$ 2,805,213	$ 2,473,050
Net premiums written	336,690	390,106	1,660,727	1,700,238
Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	448,563	420,343	1,653,647	1,394,145
Net premiums written	174,937	197,639	669,275	719,704
Agriculture Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	156,145	188,011	785,073	796,445
Net premiums written	29,634	103,536	254,771	431,007
Casualty And Other Specialty Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	128,509	115,895	375,247	291,578
Net premiums written	64,490	50,750	174,850	144,038
Professional Lines Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	80,069	62,631	231,565	176,061
Net premiums written	37,479	20,216	105,153	64,632
Property, Marine And Energy Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	83,840	53,806	261,762	130,061
Net premiums written	43,334	23,137	134,501	80,027
Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	194,034	205,767	1,151,566	1,078,905
Net premiums written	161,753	192,467	991,452	980,534
Catastrophe Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	40,660	47,173	304,900	332,193
Net premiums written	14,814	41,157	190,579	243,531
Property Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	53,423	73,807	209,683	283,107
Net premiums written	52,887	73,807	206,454	283,015
Casualty Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	42,802	23,409	149,032	139,266
Net premiums written	42,802	23,409	149,032	137,669
Professional Lines Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	31,705	21,520	209,803	131,256
Net premiums written	31,705	21,520	209,803	131,256
Specialty Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	25,444	39,858	278,148	193,083
Net premiums written	$ 19,545	$ 32,574	$ 235,584	$ 185,063

Commitments And Contingencies61

Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Reinsurance Recoverables	$ 993.3	$ 889.1
Collateral held related to ceded reinsurance agreements	320.5	199.7
Amount of letters of credit outstanding	205.1	209.9
Securities pledged as collateral obligation	134.6	130.6
Cash and investments pledged under letters of credit facility	$ 232.9	$ 240

Commitments And Contingencies62

Commitments And Contingencies (Schedule Of Percentage Of Net Premiums Written) (Details)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Revenue from External Customer [Line Items]
Percentage of net premium written	53.50%	50.50%
Aon Benfield [Member]
Revenue from External Customer [Line Items]
Percentage of net premium written	15.80%	15.40%
Willis Companies [Member]
Revenue from External Customer [Line Items]
Percentage of net premium written	12.80%	14.20%
Marsh & Mclennan Companies, Inc. [Member]
Revenue from External Customer [Line Items]
Percentage of net premium written	24.90%	20.90%

Commitments And Contingencies63

Commitments And Contingencies (Deposits) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
UNITED STATES [Member]
Statutory Accounting Practices [Line Items]
Assets Held by Insurance Regulators	$ 208.9	$ 205.2

Commitments And Contingencies C

Commitments And Contingencies Commitments And Contingencies (Assets Held In Trust) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Assets Held In Trust [Line Items]
Cash and cash equivalents	$ 1,242,997	$ 745,472	$ 805,716	$ 845,851
Blue Water Re Trust [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	436,800
BW Retrocessional Agreement [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	194,900
Blue Capital Re ILS Trusts [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	5,200
Endurance Reinsurance Trust [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	20,000
Reduced Collateral Trust [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	10,000
MUSIC Trust [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	21,500
Montpelier Reinsurance Trust [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	345,800
FL Trust [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	26,500
Lloyd's Capital Trust [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	211,800
Lloyd's Premiums Trust Funds [Member]
Assets Held In Trust [Line Items]
Assets Held-in-trust	261,200
Cash and cash equivalents	$ 23,600

Commitments And Contingencies65

Commitments And Contingencies Commitments And Contingencies (Lloyd's New Central Fund) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
Levy Imposed As Percentage Of Premiums Written	0.50%
Additional Contribution As Percentage Of Underwriting Capacity Maximum	3.00%
Estimated Obligation To Central Fund For Annual Contribution	$ 1
Annual Subscription Charge As Percentage Of Premium Written	0.50%
Estimated Obligation For Annual Subscription Charges	$ 1

Commitments And Contingencies66

Commitments And Contingencies (Schedule Of Future Minimum Lease Commitments) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 17,657
2,017	16,415
2,018	16,425
2,019	15,825
2,020	14,795
2021 and thereafter	30,894
Total	112,011
Total lease expenses under operating leases	$ 10,500	$ 11,600

Acquisition of Montpelier (Narr

Acquisition of Montpelier (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	Jul. 31, 2015	Sep. 30, 2015	Sep. 30, 2015
Business Acquisition [Line Items]
Total Company ordinary shares	20,686,699
Total value of Company ordinary shares	$ 1,437,519
Total special dividend consideration paid to Montpelier common shareholders	$ 451,101
Special dividend paid per Montpelier common share and restricted share unit	$ 9.89
Acquisition transaction-related expenses		$ 64,000	$ 68,500
Acquisition transaction costs		14,800	$ 14,800
Integration related costs		1,000
Compensation related costs		$ 48,200
Montpelier [Member]
Business Acquisition [Line Items]
Total special dividend consideration paid to Montpelier common shareholders	$ 451,101

Acquisition of Montpelier (Purc

Acquisition of Montpelier (Purchase Price) (Details) - USD ($) $ / shares in Units, $ in Thousands		Jul. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Number of Montpelier common shares outstanding immediately prior to the closing of the acquisition			66,606,820	44,765,153
Exchange ratio		0.472
Total Company ordinary shares		20,686,699
Company ordinary share closing price on July 31, 2015		$ 69.49
Total value of Company ordinary shares		$ 1,437,519
Fair value of restricted share units attributable to service period prior to merger date(1)	[1]	33,327
Total consideration		$ 1,470,846
Special dividend paid per Montpelier common share and restricted share unit		$ 9.89
Total special dividend consideration paid to Montpelier common shareholders		$ 451,101
Total consideration received by Montpelier common shareholders		1,921,947
Net purchase price		$ 1,470,846
Montpelier [Member]
Business Acquisition [Line Items]
Number of Montpelier common shares outstanding immediately prior to the closing of the acquisition		43,827,753
Number of Montpelier common shares and restricted share units eligible for special dividend		45,611,810
Total special dividend consideration paid to Montpelier common shareholders		$ 451,101
[1]	Outstanding Montpelier restricted share units were assumed by the Company and adjusted as of the Closing Date to represent the right to receive 0.472 Company ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of Company ordinary shares. The fair value of the Montpelier restricted share units was determined based on the closing price of the Company's ordinary shares on the Closing Date. The resulting fair value of the restricted share units was apportioned as purchase consideration based on service provided to Montpelier as of the Closing Date with the remaining fair value of these restricted share units to be recognized prospectively over the restricted share units' remaining vesting period.

Acquisition of Montpelier (Fair

Acquisition of Montpelier (Fair Value of Net Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Thousands	Jul. 31, 2015	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Business Acquisition [Line Items]
Montpelier shareholders' equity attributable to controlling interest prior to Special Dividend		$ 4,796,870	$ 3,185,182	$ 3,120,454
Cash and cash equivalents (Special Dividend on Montpelier common shares and Montpelier equity awards)	$ (451,101)
Fixed maturity investments, trading at fair value	(11,100)
Deferred acquisition costs	(91,713)
Reinsurance recoverable on unpaid losses	(675)
Other assets	(12,459)
Reserve for losses and loss expenses	10,822
Debt	21,123
Deferred tax liability	(18,346)
Non-controlling interest	25,615
Total adjustments for fair value by applicable balance sheet caption	(76,733)
Total adjustments for fair value by applicable balance sheet caption and identifiable intangible assets	274,067
Estimated fair value of net assets acquired and identifiable intangible assets	1,383,221
Total consideration paid by Endurance Holdings	$ 1,470,846
Estimated total consideration over the fair value of net assets acquired assigned to goodwill		$ 177,426	$ 91,238	$ 91,326
Weighted average useful life of acquired finite-lived intangible assets,	8 years
Montpelier [Member]
Business Acquisition [Line Items]
Montpelier shareholders' equity attributable to controlling interest prior to Special Dividend	$ 1,560,255
Cash and cash equivalents (Special Dividend on Montpelier common shares and Montpelier equity awards)	(451,101)
Adjusted shareholders' equity of Montpelier as of July 31, 2015	1,109,154
Identifiable indefinite lived intangible assets (insurance licenses, Lloyd's syndicate capacity and asset management agreements)	57,600
Identifiable finite lived intangible assets (non-contractual relationships, Lloyd's syndicate distribution channel, renewal rights, value of business acquired, trademarks and trade names, covenants not to compete and asset management agreements)	293,200
Estimated total consideration over the fair value of net assets acquired assigned to goodwill	$ 87,625

Acquisition of Montpelier (Inta

Acquisition of Montpelier (Intangible Assets) (Details) - USD ($) $ in Thousands	Jul. 31, 2015	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Acquisition [Line Items]
Identifiable intangible assets, before amortization, at July 31, 2015	$ 350,800
Amortization (from July 31, 2015 through September 30, 2015)		$ (9,734)	$ (11,318)	$ (1,623)	$ (14,496)	$ (4,863)
Net identifiable intangible assets at September 30, 2015 related to the acquisition of Montpelier		$ 341,066	$ 341,066		$ 341,066
Key non-contractual relationships
Business Acquisition [Line Items]
Finite lived intangible assets acquired	$ 71,800
Finite-Lived Intangible Asset, Useful Life	10 years
Other non-contractual relationships
Business Acquisition [Line Items]
Finite lived intangible assets acquired	$ 22,400
Finite-Lived Intangible Asset, Useful Life	3 years
Trade names
Business Acquisition [Line Items]
Finite lived intangible assets acquired	$ 1,800
Insurance licenses
Business Acquisition [Line Items]
Indefinite lived intangible assets acquired	1,900
Non-compete agreements
Business Acquisition [Line Items]
Finite lived intangible assets acquired	5,700
Lloyd's syndicate capacity
Business Acquisition [Line Items]
Indefinite lived intangible assets acquired	48,300
Lloyd's syndicate distribution channel
Business Acquisition [Line Items]
Finite lived intangible assets acquired	$ 18,400
Finite-Lived Intangible Asset, Useful Life	10 years
Renewal rights
Business Acquisition [Line Items]
Finite lived intangible assets acquired	$ 82,100
Finite-Lived Intangible Asset, Useful Life	15 years
Value of business acquired
Business Acquisition [Line Items]
Finite lived intangible assets acquired	$ 88,400
Finite-Lived Intangible Asset, Useful Life	2 years
Asset management agreements
Business Acquisition [Line Items]
Identifiable intangible assets, before amortization, at July 31, 2015	$ 10,000

Acquisition of Montpelier Acqui

Acquisition of Montpelier Acquisition of Montpelier (Goodwill) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Goodwill [Roll Forward]
Balance at December 31, 2015	$ 91,238
Additions	87,625
Foreign currency translation	(1,437)
Balance at September 30, 2015	$ 177,426

Acquisition of Montpelier (Fina

Acquisition of Montpelier (Financial Results) (Details) - USD ($) $ in Thousands		2 Months Ended	3 Months Ended
		Sep. 30, 2015	Sep. 30, 2015
Business Acquisition [Line Items]
Compensation related costs			$ 48,200
Montpelier [Member]
Business Acquisition [Line Items]
Total revenues		$ 94,249
Net loss attributable to the Company's common shareholders(1)	[1]	$ (10,058)
[1]	Includes $48.2 million of compensation-related costs associated with terminating employees of Montpelier.

Acquisition of Montpelier (Supp

Acquisition of Montpelier (Supplemental Proforma Information) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Combinations [Abstract]
Total revenues	$ 627,394	$ 701,332	$ 1,886,038	$ 2,030,119
Net income available to Endurance Holdings' common shareholders	$ 100,046	$ 86,755	$ 345,086	$ 264,799

Debt And Financing Arrangemen74

Debt And Financing Arrangements (Details) - USD ($) $ in Millions	May. 15, 2015	May. 01, 2015	Sep. 30, 2015	Dec. 31, 2014	Apr. 19, 2012
Line of Credit Facility [Line Items]
Maximum borrowing capacity					$ 700
Increase to credit facility permitted			$ 350
Minimum Net Worth Required for Compliance			1,800
Amount of letters of credit outstanding			$ 205.1	$ 209.9
Term of LIBOR swap			5 years
Tranche 1 [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 560
Tranche 2 [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			140
Blue Capital Reinsurance Holdings [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			20
Short-term Debt			$ 9
Term of facility		364 days
Annual guarantee fee percentage			0.125%
Debt Covenant Minimum Net Worth To Maintain			70.00%
Blue Capital Global Reinsurance Fund [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 20
Short-term Debt			$ 6
Term of facility	364 days
Annual guarantee fee percentage			0.125%
LOC Agreements [Member]
Line of Credit Facility [Line Items]
Amount of letters of credit outstanding			$ 27.6	5.9
Due November 2 2015 [Member] | Blue Capital Reinsurance Holdings [Member]
Line of Credit Facility [Line Items]
Future repayments of lines of credit			$ 4
Annual interest rate			1.41%
Due December 21 2015 [Member] | Blue Capital Reinsurance Holdings [Member]
Line of Credit Facility [Line Items]
Future repayments of lines of credit			$ 5
Annual interest rate			1.45%
Due February 1, 2016 [Member] | Tranche 1 [Member]
Line of Credit Facility [Line Items]
Future repayments of lines of credit			$ 3
Annual interest rate			1.54%
Due February 12, 2016 [Member] | Tranche 2 [Member]
Line of Credit Facility [Line Items]
Future repayments of lines of credit			$ 3
Annual interest rate			1.51%
Seven Percent Senior Notes [Member]
Line of Credit Facility [Line Items]
Fixed interest rate percentage			7.00%
Debt Instrument, Face Amount			$ 335
Six Point One Five Percent Senior Notes [Member]
Line of Credit Facility [Line Items]
Fixed interest rate percentage			6.15%
Debt Instrument, Face Amount			$ 200
Four Point Seven Percent Senior Notes [Member]
Line of Credit Facility [Line Items]
Fixed interest rate percentage			4.70%
Debt Instrument, Face Amount			$ 300
Trust Preferred Securities [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount			$ 100
Debt Instrument, Description of Variable Rate Basis			3-month
Debt Instrument, Redemption Price, Percentage			100.00%
Credit Facility [Member]
Line of Credit Facility [Line Items]
Amount of letters of credit outstanding			$ 199.6	$ 204
Maximum [Member]
Line of Credit Facility [Line Items]
Leverage Ratio			35.00%
Maximum [Member] | Blue Capital Reinsurance Holdings [Member]
Line of Credit Facility [Line Items]
Debt Covenant Debt To Total Capitalization Required			22.50%
Maximum [Member] | LOC Agreements [Member]
Line of Credit Facility [Line Items]
Line Of Credit Facility Used Capacity Commitment Fee Percentage			0.45%
Minimum [Member] | LOC Agreements [Member]
Line of Credit Facility [Line Items]
Line Of Credit Facility Used Capacity Commitment Fee Percentage			0.30%
LIBOR Swap [Member]
Line of Credit Facility [Line Items]
Fixed interest rate percentage			4.905%
Debt Instrument, Basis Spread on Variable Rate			3.80%
Term of LIBOR swap			5 years

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Related Party Transaction [Line Items]
Investment expenses	$ 4,218,000	$ 3,398,000	$ 11,049,000	$ 10,676,000
Credit Agreement [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	$ 100,000		$ 100,000
BlackRock Inc [Member]
Related Party Transaction [Line Items]
Ordinary shares owned by related parties	3.9		3.9
Percentage of ordinary shares owned by related parties	5.80%		5.80%
Investment expenses	$ 800,000	$ 800,000	$ 2,500,000	$ 2,300,000
Accrued investment expenses	$ 1,100,000		$ 1,100,000		$ 1,500,000
Blue Capital Reinsurance Holdings [Member]
Related Party Transaction [Line Items]
Related Party Transaction Termination Fee Payable As Percentage Of Shareholders Equity	5.00%		5.00%
Related Party Transaction Termination Fee Payable	$ 9,100,000		$ 9,100,000
Due from Related Parties	2,000,000		2,000,000
Blue Capital Reinsurance Holdings [Member] | Investment Management Agreement [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	400,000		400,000
Blue Capital Reinsurance Holdings [Member] | Administrative Services Agreement [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	100,000		100,000
Blue Capital Reinsurance Holdings [Member] | Underwriting And Insurance Management Agreement [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	$ 100,000		$ 100,000
Blue Capital Reinsurance Holdings [Member] | Credit Agreement [Member]
Related Party Transaction [Line Items]
Annual guarantee fee percentage			0.125%
Blue Capital Global Reinsurance Fund [Member] | Credit Agreement [Member]
Related Party Transaction [Line Items]
Annual guarantee fee percentage			0.125%