Endurance Specialty (ENH) 10-Q 7 Aug 15 2015 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Aug. 04, 2015
Document and Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
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		65,851,598

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
ASSETS
Fixed maturity investments, available for sale at fair value (amortized cost: $4,899,351 and $5,032,506 at June 30, 2015 and December 31, 2014, respectively)	$ 4,933,776	$ 5,092,581
Short-term investments, available for sale at fair value (amortized cost: $16,368 and $9,015 at June 30, 2015 and December 31, 2014, respectively)	16,366	9,014
Equity securities, available for sale at fair value (cost: $407,714 and $303,922 at June 30, 2015 and December 31, 2014, respectively)	420,411	331,368
Other investments	623,868	541,454
Total investments	5,994,421	5,974,417
Cash and cash equivalents	622,642	745,472
Premiums receivable, net	1,665,990	883,450
Insurance and reinsurance balances receivable	108,162	122,214
Deferred acquisition costs	296,568	207,368
Prepaid reinsurance premiums	668,964	354,940
Reinsurance recoverable on unpaid losses	785,472	670,795
Reinsurance recoverable on paid losses	157,287	218,291
Accrued investment income	25,118	27,183
Goodwill and intangible assets	150,296	153,405
Deferred tax asset	46,779	48,995
Net receivable on sales of investments	21,420	38,877
Other assets	172,162	199,375
Total assets	10,715,281	9,644,782
LIABILITIES
Reserve for losses and loss expenses	3,833,525	3,846,859
Reserve for unearned premiums	2,046,933	1,254,519
Deposit liabilities	13,376	15,136
Reinsurance balances payable	632,457	375,711
Debt	528,123	527,715
Net payable on purchases of investments	82,375	151,682
Other liabilities	275,586	287,978
Total liabilities	$ 7,412,375	$ 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 - 45,156,845 issued and outstanding (2014 - 44,765,153)	45,157	44,765
Additional paid-in capital	610,585	598,226
Accumulated other comprehensive income	36,965	76,706
Retained earnings	2,592,999	2,448,285
Total shareholders' equity	3,302,906	3,185,182
Total liabilities and shareholders' equity	$ 10,715,281	$ 9,644,782

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Available-for-sale Securities [Abstract]
Fixed maturity investments, available for sale, amortized cost	$ 4,899,351	$ 5,032,506
Short-term investments, available for sale, amortized cost	16,368	9,015
Equity securities, available for sale, cost	407,714	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	45,156,845	44,765,153
Common stock, shares outstanding	45,156,845	44,765,153

Condensed Consolidated Statemen

Condensed Consolidated Statements Of Income And Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenues
Gross premiums written	$ 861,184	$ 689,425	$ 2,162,616	$ 1,846,940
Ceded premiums written	(302,101)	(177,998)	(838,579)	(536,808)
Net premiums written	559,083	511,427	1,324,037	1,310,132
Change in unearned premiums	(100,948)	(29,889)	(476,043)	(432,328)
Net premiums earned	458,135	481,538	847,994	877,804
Net investment income	32,252	39,302	74,113	80,292
Net realized and unrealized gains	9,680	3,411	27,869	8,283
Total other-than-temporary impairment losses	(424)	(198)	(1,073)	(309)
Portion of loss recognized in other comprehensive (loss) income	0	0	0	0
Net impairment losses recognized in earnings	(424)	(198)	(1,073)	(309)
Other underwriting income (loss)	1,389	(4,824)	3,795	(6,062)
Total revenues	501,032	519,229	952,698	960,008
Expenses
Net losses and loss expenses	239,122	259,196	411,058	436,092
Acquisition expenses	84,971	78,601	167,064	150,758
General and administrative expenses	54,965	58,312	109,855	117,813
Corporate expenses	12,634	28,143	24,902	41,848
Amortization of intangibles	1,579	1,623	3,178	3,240
Net foreign exchange losses	12,981	319	20,533	3,283
Interest expense	9,062	9,732	18,121	18,783
Total expenses	415,314	435,926	754,711	771,817
Income before income taxes	85,718	83,303	197,987	188,191
Income tax expense	(1,512)	(140)	(5,302)	(548)
Net income	84,206	83,163	192,685	187,643
Preferred dividends	(8,188)	(8,188)	(16,376)	(16,376)
Net income available to common and participating common shareholders	76,018	74,975	176,309	171,267
Comprehensive income
Net income	84,206	83,163	192,685	187,643
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 $2,825 and ($5,916) for the six months ended June 30, 2015 and 2014, respectively)	(66,979)	37,659	(42,490)	61,039
Foreign currency translation adjustments	26,163	8,998	2,705	12,223
Reclassification adjustment for net losses on derivative designated as cash flow hedge included in net income	22	22	44	45
Other comprehensive (loss) income	(40,794)	46,679	(39,741)	73,307
Comprehensive income	$ 43,412	$ 129,842	$ 152,944	$ 260,950
Per share data
Basic earnings per common share	$ 1.69	$ 1.68	$ 3.92	$ 3.84
Diluted earnings per common share	1.68	1.68	3.91	3.84
Dividend per common share	$ 0.35	$ 0.34	$ 0.70	$ 0.68

Condensed Consolidated Stateme5

Condensed Consolidated Statements Of Income And Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Other comprehensive (loss) income, net unrealized holding (losses) gains on investments arising during the period, tax	$ 2,825	$ (5,916)

Condensed Consolidated Stateme6

Condensed Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Shares [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 Income [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			337	900
Settlement of equity awards				(4,039)
Stock-based compensation expense				17,714
Foreign currency translation adjustments	$ 12,223				12,223
Net unrealized holding (losses) gains arising during the period, net of other-than-temporary impairment losses and reclassification adjustment	61,039					61,039
Net change from current period hedging transactions, net of reclassification adjustment							45
Net income	187,643								187,643
Dividends on preferred shares	(16,376)								(16,376)
Dividends on common shares									(30,360)
Balance, end of period at Jun. 30, 2014	3,115,675	17,200	44,706	583,691	30,859	106,989	(1,810)	$ 136,038	2,334,040
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			392	569
Settlement of equity awards				(6,092)
Stock-based compensation expense				17,882
Foreign currency translation adjustments	2,705				2,705
Net unrealized holding (losses) gains arising during the period, net of other-than-temporary impairment losses and reclassification adjustment	(42,490)					(42,490)
Net change from current period hedging transactions, net of reclassification adjustment							44
Net income	192,685								192,685
Dividends on preferred shares	(16,376)								(16,376)
Dividends on common shares									(31,595)
Balance, end of period at Jun. 30, 2015	$ 3,302,906	$ 17,200	$ 45,157	$ 610,585	$ (4,923)	$ 43,610	$ (1,722)	$ 36,965	$ 2,592,999

Condensed Consolidated Stateme7

Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows provided by operating activities
Net income	$ 192,685	$ 187,643
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of net premium on investments	23,090	22,253
Amortization of other intangibles and depreciation	12,695	10,673
Net realized and unrealized gains	(27,869)	(8,283)
Net impairment losses recognized in earnings	1,073	309
Deferred taxes	5,041	4
Stock-based compensation expense	17,882	17,714
Equity in earnings of other investments	(15,958)	(24,326)
Premiums receivable, net	(782,540)	(711,660)
Insurance and reinsurance balances receivable	14,052	(7,028)
Deferred acquisition costs	(89,200)	(71,235)
Prepaid reinsurance premiums	(314,024)	(236,924)
Reinsurance recoverable on unpaid losses	(114,677)	(12,385)
Reinsurance recoverable on paid losses	61,004	18,526
Accrued investment income	2,065	(2,281)
Other assets	3,700	4,271
Reserve for losses and loss expenses	(13,334)	(38,866)
Reserve for unearned premiums	792,414	670,968
Deposit liabilities	(1,760)	2,529
Reinsurance balances payable	256,746	197,234
Other liabilities	404	531
Net cash flows provided by operating activities	23,489	19,667
Cash flows used in investing activities
Proceeds from sales of available for sale investments	2,501,712	2,060,744
Proceeds from maturities and calls on available for sale investments	294,966	284,656
Proceeds from the redemption of other investments	36,523	19,703
Purchases of available for sale investments	(2,833,981)	(2,345,876)
Purchases of other investments	(102,979)	(26,541)
Net settlements of other assets	31,881	14,174
Purchases of fixed assets	(15,048)	(25,706)
Net cash paid for subsidiary acquisition	(68)	(40)
Net cash flows used in investing activities	(86,994)	(18,886)
Cash flows used in financing activities
Issuance of common shares, net of forfeitures	817	1,128
Settlement of equity awards	(6,092)	(4,039)
Bridge facility costs paid	0	(4,750)
Proceeds from issuance of debt	728	373
Repayments and repurchases of debt	(435)	(244)
Dividends on preferred shares	(16,376)	(16,376)
Dividends on common shares	(31,543)	(30,343)
Net cash flows used in financing activities	(52,901)	(54,251)
Effect of exchange rate changes on cash and cash equivalents	(6,424)	8,647
Net decrease in cash and cash equivalents	(122,830)	(44,823)
Cash and cash equivalents, beginning of period	745,472	845,851
Cash and cash equivalents, end of period	$ 622,642	$ 801,028

General

General	6 Months Ended
	Jun. 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 subsidiaries: Operating Subsidiaries Domicile Endurance Specialty Insurance Ltd. Bermuda Endurance Worldwide Insurance 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

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	2. Summary of significant accounting policies The accompanying unaudited condensed 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 six months ended June 30, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 . The unaudited condensed 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 unaudited condensed 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 unaudited condensed 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. In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 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 consolidated financial statements. 2. Summary of significant accounting policies, cont'd. 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 consolidated financial statements. 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 consolidated financial statements.

Investments

Investments	6 Months Ended
	Jun. 30, 2015
Investments [Abstract]
Investments	3. Investments Composition of Net Investment Income and of Invested Assets The components of net investment income for the three and six months ended June 30, 2015 and 2014 are as follows: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Available for sale investments $ 31,705 $ 31,619 $ 63,922 $ 61,946 Other investments 3,570 10,785 15,958 24,327 Cash and cash equivalents 434 511 1,064 1,297 35,709 42,915 $ 80,944 $ 87,570 Investment expenses (3,457 ) (3,613 ) (6,831 ) (7,278 ) Net investment income $ 32,252 $ 39,302 $ 74,113 $ 80,292 The following table summarizes the composition of the investment portfolio by investment type at June 30, 2015 and December 31, 2014 : June 30, 2015 December 31, 2014 Type of Investment Fair Value Percentage Fair Value Percentage Fixed maturity investments $ 4,933,776 75.3 % $ 5,092,581 77.1 % Cash and cash equivalents (1) 561,687 8.6 % 632,667 9.6 % Other investments (2) 623,868 9.5 % 541,454 8.2 % Short-term investments 16,366 0.2 % 9,014 0.1 % Equity securities 420,411 6.4 % 331,368 5.0 % Total $ 6,556,108 100.0 % $ 6,607,084 100.0 % (1) Includes net receivable on sales of investments and net payable on purchases of investments. (2) Consists of investments in alternative funds and specialty funds. 3. Investments, cont'd. The following table summarizes the composition by investment rating of the fixed maturity and short-term investments at June 30, 2015 and December 31, 2014 . In some cases, where bonds are unrated, the rating of the issuer has been applied. June 30, 2015 December 31, 2014 Ratings (1) Fair Value Percentage Fair Value Percentage U.S. government and agencies securities $ 483,511 9.8 % $ 587,411 11.5 % AAA / Aaa 1,168,977 23.6 % 1,206,252 23.6 % AA / Aa 1,614,866 32.6 % 1,717,343 33.7 % A / A 1,051,739 21.3 % 1,045,301 20.5 % BBB 505,731 10.2 % 427,018 8.4 % Below BBB 105,825 2.1 % 96,244 1.9 % Not rated 19,493 0.4 % 22,026 0.4 % Total $ 4,950,142 100.0 % $ 5,101,595 100.0 % (1) The credit rating for each security reflected above was determined based on the rating assigned to the individual security by Standard & Poor's Financial Services LLC ("Standard & Poor's"). If a rating is not supplied by Standard & Poor's, the equivalent rating supplied by Moody's Investors Service, Inc. ("Moody's"), Fitch Ratings, Inc., or DBRS, Inc. is used. Contractual maturities of the Company’s fixed maturity and short-term investments are shown below as of June 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. June 30, 2015 December 31, 2014 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 145,833 $ 146,729 $ 126,921 $ 127,821 Due after one year through five years 1,513,058 1,516,820 1,627,154 1,632,259 Due after five years through ten years 435,077 434,624 474,959 479,138 Due after ten years 48,466 49,940 43,314 46,720 Residential mortgage-backed securities 1,062,261 1,076,732 1,149,536 1,175,006 Commercial mortgage-backed securities 992,858 1,003,518 960,598 979,419 Collateralized loan and debt obligations 325,750 327,642 247,510 248,011 Asset-backed securities 392,416 394,137 411,529 413,221 Total $ 4,915,719 $ 4,950,142 $ 5,041,521 $ 5,101,595 In addition to the Company's fixed maturity, short-term and equity investments, the Company invests in (i) hedge funds and private investment funds that generally invest in senior secured bank debt, high yield credit, distressed debt, distressed real estate, derivatives, and equity long/short strategies ("alternative funds") and (ii) high yield loan funds ("specialty funds"). The Company's alternative funds and specialty funds are recorded on the Company's balance sheet as "other investments." At June 30, 2015 and December 31, 2014 , the Company had invested, net of capital returned, a total of $452.7 million and $387.2 million , respectively, in other investments. At June 30, 2015 and December 31, 2014 , the carrying value of other investments was $623.9 million and $541.5 million , respectively. 3. Investments, cont'd. The following table summarizes the composition and redemption restrictions of other investments as of June 30, 2015 and December 31, 2014 : June 30, 2015 Market Value Unfunded Commitments Ineligible for Redemption over next 12 months Alternative funds Hedge funds $ 458,681 $ — $ 81,153 Private investment funds 78,574 53,151 78,574 Total alternative funds 537,255 53,151 159,727 Specialty funds High yield loan funds 86,613 — — Total specialty funds 86,613 — — Total other investments $ 623,868 $ 53,151 $ 159,727 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 82.3% 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. 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. 3. Investments, cont'd. 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 six months ended June 30, 2015 and 2014 is as follows: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Gross realized gains on investment sales $ 14,647 $ 7,387 $ 37,313 $ 17,634 Gross realized losses on investment sales (5,058 ) (5,319 ) (9,954 ) (11,303 ) Change in fair value of derivative financial instruments (1) 91 1,343 510 1,952 Net realized and unrealized gains $ 9,680 $ 3,411 $ 27,869 $ 8,283 (1) For additional information on the Company's derivative financial instruments, see Note 7. Unrealized Gains and Losses and Other-Than-Temporary Impairments The Company classifies 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 and non-credit other-than-temporary impairment (“OTTI”) losses on the Company’s securities classified as available for sale at June 30, 2015 and December 31, 2014 are as follows: June 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Non-Credit OTTI (2) Fixed maturity investments U.S. government and agencies securities $ 480,584 $ 5,285 $ (2,358 ) $ 483,511 $ — U.S. state and municipal securities 40,893 164 (520 ) 40,537 — Foreign government securities 156,874 1,293 (534 ) 157,633 — Government guaranteed corporate securities 30,167 434 (32 ) 30,569 — Corporate securities 1,417,548 8,872 (6,923 ) 1,419,497 — Residential mortgage-backed securities 1,062,261 19,786 (5,315 ) 1,076,732 (2,940 ) Commercial mortgage-backed securities 992,858 15,152 (4,492 ) 1,003,518 — Collateralized loan and debt obligations (1) 325,750 2,166 (274 ) 327,642 — Asset-backed securities 392,416 2,069 (348 ) 394,137 — Total fixed maturity investments 4,899,351 55,221 (20,796 ) 4,933,776 (2,940 ) Short-term investments 16,368 — (2 ) 16,366 — Total fixed income investments $ 4,915,719 $ 55,221 $ (20,798 ) $ 4,950,142 $ (2,940 ) Equity securities Equity investments $ 281,005 $ 16,678 $ (6,331 ) $ 291,352 $ — Emerging market debt funds 61,874 — (1,837 ) 60,037 — Convertible funds 46,331 2,240 — 48,571 — Preferred equity investments 13,581 1,993 (46 ) 15,528 — Short-term fixed income fund 4,923 — — 4,923 — Total equity securities $ 407,714 $ 20,911 $ (8,214 ) $ 420,411 $ — (1) Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million . (2) Represents total OTTI recognized in accumulated other comprehensive income. It does not include the change in fair value subsequent to the impairment measurement date. At June 30, 2015 , the gross unrealized loss related to fixed income investments for which a non-credit OTTI was recognized in accumulated other comprehensive income was nil . 3. Investments, cont'd. December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Non-Credit OTTI (2) 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 (3,233 ) Commercial mortgage-backed securities 960,598 21,374 (2,553 ) 979,419 (5 ) 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 (3,238 ) Short-term investments 9,015 — (1 ) 9,014 — Total fixed income investments $ 5,041,521 $ 75,692 $ (15,618 ) $ 5,101,595 $ (3,238 ) 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 . (2) Represents total OTTI recognized in accumulated other comprehensive income. It does not include the change in fair value subsequent to the impairment measurement date. At December 31, 2014 , the gross unrealized loss related to fixed income investments for which a non-credit OTTI was recognized in accumulated other comprehensive income was nil . 3. Investments, cont'd. The following tables summarize, for all available for sale securities in an unrealized loss position at June 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 June 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 $ (1,687 ) $ 149,003 $ (671 ) $ 16,995 $ (2,358 ) $ 165,998 U.S. state and municipal securities (520 ) 21,615 — — (520 ) 21,615 Foreign government securities (413 ) 46,557 (121 ) 2,849 (534 ) 49,406 Government guaranteed corporate securities (32 ) 3,300 — — (32 ) 3,300 Corporate securities (6,428 ) 731,507 (495 ) 29,369 (6,923 ) 760,876 Residential mortgage-backed securities (4,014 ) 344,126 (1,301 ) 52,474 (5,315 ) 396,600 Commercial mortgage-backed securities (3,603 ) 324,191 (889 ) 35,150 (4,492 ) 359,341 Collateralized loan and debt obligations (215 ) 95,946 (59 ) 27,618 (274 ) 123,564 Asset-backed securities (208 ) 101,724 (140 ) 12,983 (348 ) 114,707 Total fixed maturity investments (17,120 ) 1,817,969 (3,676 ) 177,438 (20,796 ) 1,995,407 Short-term investments (2 ) 1,506 — — (2 ) 1,506 Total fixed income investments $ (17,122 ) 1,819,475 (3,676 ) 177,438 (20,798 ) 1,996,913 Equity securities Equity investments $ (6,315 ) $ 144,058 $ (16 ) $ 133 $ (6,331 ) $ 144,191 Emerging market debt funds (1,837 ) 60,037 — — (1,837 ) 60,037 Preferred equity investments (46 ) 2,917 — — (46 ) 2,917 Total equity securities $ (8,198 ) $ 207,012 $ (16 ) $ 133 $ (8,214 ) $ 207,145 (1) Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive income at June 30, 2015 . As of June 30, 2015 , 981 available for sale securities were in an unrealized loss position aggregating $29.0 million . Of those, 92 securities with aggregated unrealized losses of $3.7 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 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. The analysis of OTTI for the three and six months ended June 30, 2015 and 2014 is as follows: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Total other-than-temporary impairment losses $ (424 ) $ (198 ) $ (1,073 ) $ (309 ) Portion of loss recognized in other comprehensive (loss) income — — — — Net impairment losses recognized in earnings $ (424 ) $ (198 ) $ (1,073 ) $ (309 ) 3. Investments, cont'd. Of the $0.4 million ( 2014 : $0.2 million ) of OTTI losses recognized by the Company in the second quarter of 2015 , the majority were related to fixed maturity investments and equity investments for which the Company has subsequently made a decision to sell. The increase in gross unrealized losses on the Company's fixed income investments at June 30, 2015 compared to December 31, 2014 was primarily due to an increase in interest rates and widening of credit spreads during the six months ended June 30, 2015 . At June 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 June 30, 2015 . The following table provides a roll-forward of the amount related to credit losses for the Company's available for sale investments recognized in earnings for which a portion of an OTTI loss was recognized in accumulated other comprehensive income for the three and six months ended June 30, 2015 and 2014 : Three Months Ended Six Months Ended 2015 2014 2015 2014 Beginning balance $ (795 ) $ (1,520 ) $ (838 ) $ (1,553 ) Addition for the amount related to the credit loss for which an other-than-temporary impairment was not previously recognized — — — — Addition for the amount related to the credit loss for which an other-than-temporary impairment was previously recognized — — — — Reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security — — — — Reductions for securities sold during the period 39 79 82 112 Ending balance $ (756 ) $ (1,441 ) $ (756 ) $ (1,441 ) Variable Interest Entities Entities that do not have sufficient equity at risk to allow the entity to finance its activities without additional financial support or in which the equity investors, as a group, do not have the characteristics of a controlling financial interest are referred to as variable interest entities ("VIE"). A VIE is consolidated by the variable interest holder that is determined to have the controlling financial interest (primary beneficiary) as a result of having both the power to direct the activities of a VIE that most significantly impact the VIE's economic performance and the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. 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 is involved in the normal course of business with VIEs primarily 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 determined that it was not the primary beneficiary for any of these investments as of June 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 Condensed Consolidated Balance Sheets and any unfunded investment commitments.

Fair Value Measurement

Fair Value Measurement	6 Months Ended
	Jun. 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. • 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. 4. Fair value measurement, cont'd. • 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 and the 7.0% Senior Notes due July 15, 2034 (the "Senior Notes"). 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 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 and other financial instruments not described above approximated their fair values at June 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 available for sale investments, other investments, other assets and liabilities and debt categorized by the level within the hierarchy in which the fair value measurements fall at June 30, 2015 : Fair Value Measurements at June 30, 2015 Total at June 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 $ 483,511 $ 34,235 $ 449,276 $ — U.S. state and municipal securities 40,537 — 40,537 — Foreign government securities 157,633 — 157,633 — Government guaranteed corporate securities 30,569 — 30,569 — Corporate securities 1,419,497 — 1,417,048 2,449 Residential mortgage-backed securities 1,076,732 — 1,076,732 — Commercial mortgage-backed securities 1,003,518 — 1,003,135 383 Collateralized loan and debt obligations 327,642 — 325,767 1,875 Asset-backed securities 394,137 — 394,137 — Total fixed maturity investments 4,933,776 34,235 4,894,834 4,707 Equity securities Equity investments 291,352 157,657 133,695 — Emerging market debt funds 60,037 — 60,037 — Convertible funds 48,571 — 48,571 — Preferred equity investments 15,528 — 15,528 — Short-term fixed income fund 4,923 4,923 — — Total equity securities 420,411 162,580 257,831 — Short-term investments 16,366 — 16,366 — Other investments 623,868 — — 623,868 Other assets (see Note 7) 70,570 — 46,879 23,691 Total assets $ 6,064,991 $ 196,815 $ 5,215,910 $ 652,266 Liabilities Other liabilities (see Note 7) $ 44,383 $ — $ 22,199 $ 22,184 Debt 596,902 — 596,902 — Total liabilities $ 641,285 $ — $ 619,101 $ 22,184 During the three months ended June 30, 2015 , $0.2 million of asset-backed securities were transferred into Level 3 as no observable inputs were available, and $4.9 million of primarily asset-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. During the six months ended June 30, 2015 , $2.0 million of collateralized debt and loan obligations and asset-backed securities 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 available for sale 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 10.8% and 9.5% of the Company's total available for sale investments, other investments and derivative instruments at June 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 six months ended June 30, 2015 . 4. Fair value measurement, cont'd. Other assets and other liabilities measured at fair value at June 30, 2015 include assets of $23.7 million ( 2014 - $25.6 million ) and liabilities of $22.2 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 June 30, 2015 and December 31, 2014 : June 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 $ 1,507 Historical Analysis and Simulation Correlation 0 1 Actual Weather curve $ 2,200 $ 10,600 Actual Commodity curve $ — $ 14 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 $ — $ — Actual There were no impairment losses on Level 3 securities recognized in earnings for the three and six months ended June 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 June 30, 2015 and 2014 : Three Months Ended June 30, 2015 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 9,500 $ 575,974 $ 15,223 $ 600,697 $ (17,385 ) Total equity income and realized gains included in earnings — 14,469 — 14,469 — Total equity losses and losses included in earnings (2 ) (10,899 ) — (10,901 ) — Total income included in other underwriting income (loss) — — 3,499 3,499 7,806 Total loss included in other underwriting income (loss) — — (4,152 ) (4,152 ) (3,691 ) Change in unrealized gains included in other comprehensive (loss) income 18 — — 18 — Change in unrealized losses included in other comprehensive (loss) income (64 ) — — (64 ) — Purchases — 63,658 — 63,658 — Issues — — 9,121 9,121 (12,324 ) Sales (96 ) (19,334 ) — (19,430 ) — Settlements — — — — 3,410 Transfers in to Level 3 237 — — 237 — Transfers out of Level 3 (4,886 ) — — (4,886 ) — Level 3, end of period $ 4,707 $ 623,868 $ 23,691 $ 652,266 $ (22,184 ) Three Months Ended June 30, 2014 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 8,985 $ 621,914 $ 8,532 $ 639,431 $ (13,448 ) Total equity income and realized gains included in earnings 36 16,286 — 16,322 — Total equity losses and losses included in earnings — (5,501 ) — (5,501 ) — Total income included in other underwriting income (loss) — — 11,241 11,241 12,622 Total loss included in other underwriting income (loss) — — (11,722 ) (11,722 ) (12,177 ) Change in unrealized gains included in other comprehensive (loss) income 89 — — 89 — Change in unrealized losses included in other comprehensive (loss) income (36 ) — — (36 ) — Purchases — 21,867 — 21,867 — Issues — — 2,941 2,941 (5,883 ) Sales (856 ) (5,924 ) — (6,780 ) — Settlements — — — — 8,602 Transfers in to Level 3 2,886 — — 2,886 — Transfers out of Level 3 (1,589 ) — — (1,589 ) — Level 3, end of period $ 9,515 $ 648,642 $ 10,992 $ 669,149 $ (10,284 ) 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 six months ended June 30, 2015 and 2014 : Six Months Ended June 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 35,018 — 35,131 — Total equity losses and losses included in earnings (11 ) (19,060 ) — (19,071 ) — Total income included in other underwriting income (loss) — — 5,595 5,595 20,865 Total loss included in other underwriting income (loss) — — (12,994 ) (12,994 ) (7,220 ) Change in unrealized gains included in other comprehensive (loss) income 24 — — 24 — Change in unrealized losses included in other comprehensive (loss) income (193 ) — — (193 ) — Purchases — 102,979 — 102,979 — Issues — — 12,333 12,333 (18,748 ) Sales (310 ) (36,523 ) — (36,833 ) — Settlements — — (6,858 ) (6,858 ) 18,285 Transfers in to Level 3 1,970 — — 1,970 — Transfers out of Level 3 (9,176 ) — — (9,176 ) — Level 3, end of period $ 4,707 $ 623,868 $ 23,691 $ 652,266 $ (22,184 ) Six Months Ended June 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 53 35,472 — 35,525 — Total equity losses and losses included in earnings (26 ) (11,146 ) — (11,172 ) — Total income included in other underwriting income (loss) — — 15,216 15,216 20,048 Total loss included in other underwriting income (loss) — — (18,610 ) (18,610 ) (16,953 ) Change in unrealized gains included in other comprehensive income (loss) 200 — — 200 — Change in unrealized losses included in other comprehensive income (loss) (151 ) — — (151 ) — Purchases — 26,541 — 26,541 — Issues — — 3,581 3,581 (7,163 ) Sales (1,040 ) (19,703 ) — (20,743 ) — Settlements — — (3,233 ) (3,233 ) 13,353 Transfers in to Level 3 5,003 — — 5,003 — Transfers out of Level 3 (1,852 ) — — (1,852 ) — Level 3, end of period $ 9,515 $ 648,642 $ 10,992 $ 669,149 $ (10,284 )

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 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 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 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 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 share for the three and six months ended June 30, 2015 and 2014 : Three Months Ended Six Months Ended 2015 2014 2015 2014 Numerator: Net income available to common and participating common shareholders $ 76,018 $ 74,975 $ 176,309 $ 171,267 Less amount allocated to participating common shareholders (1) (2,273 ) (2,212 ) (5,237 ) (4,988 ) Net income allocated to common shareholders 73,745 72,763 $ 171,072 $ 166,279 Denominator: Weighted average shares - basic 43,736,541 43,350,911 43,640,052 43,265,200 Share equivalents: Options 150,384 — 148,204 283 Restricted shares and restricted share units 9,796 — 4,370 143 Weighted average shares - diluted 43,896,721 43,350,911 43,792,626 43,265,626 Basic earnings per common share $ 1.69 $ 1.68 $ 3.92 $ 3.84 Diluted earnings per common share $ 1.68 $ 1.68 $ 3.91 $ 3.84 (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 May 13, 2015 ( 2014 - Series A: $0.484375 , Series B: $0.468750 ). The Series A and Series B preferred share dividends were paid on June 15, 2015 to shareholders of record on May 29, 2015 . Endurance Holdings also declared a dividend of $0.35 per common share on May 20, 2015 ( 2014 - $0.34 ). The dividend was paid on June 30, 2015 to shareholders of record on June 16, 2015 . Three Months Ended Six Months Ended 2015 2014 2015 2014 Dividends declared per Series A preferred share $ 0.484375 $ 0.484375 $ 0.968750 $ 0.968750 Dividends declared per Series B preferred share $ 0.468750 $ 0.468750 $ 0.937500 $ 0.937500 Dividends declared per common share $ 0.35 $ 0.34 $ 0.70 $ 0.68

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income	6. Accumulated other comprehensive income The following tables present the changes in accumulated other comprehensive income balances by component for the three months ended June 30, 2015 and 2014 : For the Three Months Ended June 30, 2015 Losses on cash flow hedges Unrealized gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,744 ) $ 110,589 $ (31,086 ) $ 77,759 Other comprehensive (loss) income before reclassifications — (57,671 ) 26,163 (31,508 ) Amounts reclassified from accumulated other comprehensive income (1) 22 (9,308 ) — (9,286 ) Net current period other comprehensive income (loss) 22 (66,979 ) 26,163 (40,794 ) Ending balance $ (1,722 ) $ 43,610 $ (4,923 ) $ 36,965 (1) All amounts are net of tax. For the Three Months Ended June 30, 2014 Losses on cash flow hedges Unrealized gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,832 ) 69,330 $ 21,861 $ 89,359 Other comprehensive income before reclassifications — 39,676 8,998 48,674 Amounts reclassified from accumulated other comprehensive income (1) 22 (2,017 ) — (1,995 ) Net current period other comprehensive income 22 37,659 8,998 46,679 Ending balance $ (1,810 ) $ 106,989 $ 30,859 $ 136,038 (1) All amounts are net of tax. 6. Accumulated other comprehensive income, cont'd. The following tables present the changes in accumulated other comprehensive income balances by component for the six months ended June 30, 2015 and 2014 : For the Six Months Ended June 30, 2015 Losses on cash flow hedges Unrealized 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 — (16,937 ) 2,705 (14,232 ) Amounts reclassified from accumulated other comprehensive income (1) 44 (25,553 ) — (25,509 ) Net current period other comprehensive income (loss) 44 (42,490 ) 2,705 (39,741 ) Ending balance $ (1,722 ) $ 43,610 $ (4,923 ) $ 36,965 (1) All amounts are net of tax. For the Six Months Ended June 30, 2014 Losses on cash flow hedges Unrealized gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,855 ) $ 45,950 $ 18,636 $ 62,731 Other comprehensive income before reclassifications — 67,341 12,223 79,564 Amounts reclassified from accumulated other comprehensive income (1) 45 (6,302 ) — (6,257 ) Net current period other comprehensive income 45 61,039 12,223 73,307 Ending balance $ (1,810 ) $ 106,989 $ 30,859 $ 136,038 (1) All amounts are net of tax. 6. Accumulated other comprehensive income, cont'd. The following tables present the significant items reclassified out of accumulated other comprehensive income during the three months ended June 30, 2015 and 2014 : Three Months Ended June 30, 2015 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited 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 $ (9,589 ) Net realized and unrealized gains 424 Net impairment losses recognized in earnings (9,165 ) Total before income taxes (143 ) Income tax benefit $ (9,308 ) Total net of income taxes Three Months Ended June 30, 2014 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited 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 $ (2,068 ) Net realized and unrealized gains 198 Net impairment losses recognized in earnings (1,870 ) Total before income taxes (147 ) Income tax benefit $ (2,017 ) Total net of income taxes 6. Accumulated other comprehensive income, cont'd. The following tables present the significant items reclassified out of accumulated other comprehensive income during the six months ended June 30, 2015 and 2014 : Six Months Ended June 30, 2015 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 44 Interest expense 44 Total before income taxes — Income tax expense $ 44 Total net of income taxes Unrealized gains on available for sale securities $ (27,359 ) Net realized and unrealized gains 1,073 Net impairment losses recognized in earnings (26,286 ) Total before income taxes 733 Income tax expense $ (25,553 ) Total net of income taxes Six Months Ended June 30, 2014 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 45 Interest expense 45 Total before income taxes — Income tax expense $ 45 Total net of income taxes Unrealized gains on available for sale securities $ (6,331 ) Net realized and unrealized gains 309 Net impairment losses recognized in earnings (6,022 ) Total before income taxes (280 ) Income tax benefit $ (6,302 ) Total net of income taxes

Derivatives

Derivatives	6 Months Ended
	Jun. 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 fixed maturity assets 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 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. 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. 7. Derivatives, cont'd. The fair values and the related notional values of derivatives at June 30, 2015 and December 31, 2014 are shown below. June 30, 2015 December 31, 2014 Fair Value Notional Principal Amount Fair Value Notional Principal Amount Derivatives recorded in other assets Foreign exchange forward contracts $ 91 $ 24,185 $ 651 $ 42,694 Credit default swaps 27 2,190 — — Interest rate swaps 98 1,900 — — Interest rate futures 3 54,348 7 7,595 TBAs 46,660 44,700 73,231 70,000 Energy and weather contracts 23,691 76,702 25,615 81,624 Total recorded in other assets 70,570 99,504 Derivatives recorded in other liabilities Foreign exchange forward contracts $ 306 $ 26,895 $ 123 $ 20,945 Credit default swaps 1 2,099 — — Interest rate swaps 176 46,000 20 12,549 Interest rate swaptions — — 9 13,100 Interest rate futures 3 9,672 — — TBAs 21,713 20,700 18,820 18,000 Energy and weather contracts 22,184 130,539 35,366 135,050 Total recorded in other liabilities 44,383 54,338 Net derivative asset $ 26,187 $ 45,166 At June 30, 2015 , the Company's derivative assets of $70.6 million ( December 31, 2014 - $99.5 million ) and liabilities of $44.4 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 June 30, 2015 and December 31, 2014 , interest rate futures were not subject to a master netting agreement. At June 30, 2015 and December 31, 2014 , none of the Company's derivative instruments were recorded on a net basis in the Condensed Consolidated Balance Sheets. The gains and losses on the Condensed Consolidated Statements of Income and Comprehensive Income for derivatives for the three and six months ended June 30, 2015 and 2014 were as follows: Three Months Ended Six Months Ended 2015 2014 2015 2014 Total included in net foreign exchange losses from foreign exchange forward contracts $ (343 ) $ (172 ) $ 1,126 $ (399 ) Interest rate futures (27 ) 115 95 135 Credit default swaps 9 14 9 14 Interest rate swaps 320 (316 ) (235 ) (1,081 ) Interest rate swaptions — (1 ) 28 428 TBAs (211 ) 1,531 613 2,456 Total included in net realized and unrealized gains 91 1,343 510 1,952 Total included in other underwriting income (loss) from energy and weather contracts 3,258 (40 ) 6,042 (299 ) Total gains from derivatives $ 3,006 $ 1,131 $ 7,678 $ 1,254

Stock-Based Employee Compensati

Stock-Based Employee Compensation And Other Stock Plans	6 Months Ended
	Jun. 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. 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 cliff vest at the end of the three -year period. The number of performance-based restricted shares that will ultimately vest is subject to a periodic review and adjustment taking into account actual performance of the Company compared to the performance of a publicly-traded peer group of 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 and 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. Time-Based Restricted Shares The Company has issued time-based restricted shares to employees and non-employee directors. 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 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. 8. Stock-based employee compensation and other stock plans, cont'd. The fair value of the restricted share units 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 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, expired or exercised during the quarter ended June 30, 2015 . No options were granted or expired during the quarter ended June 30, 2014 . During the quarter ended June 30, 2014 , 15,000 options were exercised. During the quarter ended June 30, 2015 , 160,000 ( 2014 - 160,000 ) options vested. The total intrinsic value of options exercised during the quarter ended June 30, 2014 was $0.3 million . The Company received proceeds of $0.5 million from the exercise of options during the quarter ended June 30, 2014 . The Company issued new ordinary shares in connection with the exercise of the above options. For the quarter ended June 30, 2015 , compensation costs recognized in earnings for all options totaled $0.5 million ( 2014 - $0.9 million ). At June 30, 2015 , compensation costs not yet recognized related to unvested stock options was $1.6 million ( 2014 - $3.7 million ). No options were granted, expired or exercised during the six months ended June 30, 2015 . No options were granted or expired during the six months ended June 30, 2014 . During the six months ended June 30, 2014 , 15,000 options were exercised. During the six months ended June 30, 2015 , 160,000 ( 2014 - 160,000 ) options vested. The total intrinsic value of options exercised during the six months ended June 30, 2014 was $0.3 million . The Company received proceeds of $0.5 million from the exercise of options during the six months ended June 30, 2014 . The Company issued new ordinary shares in connection with the exercise of the above options. For the six months ended June 30, 2015 , compensation costs recognized in earnings for all options totaled $1.0 million ( 2014 - $2.0 million ). A summary of the restricted share and restricted share unit activity during the six months ended June 30, 2015 , is presented below: Number of Shares/Units Aggregate Intrinsic Value Unvested, beginning of period 1,290,894 Granted 504,352 Settled (445,083 ) Forfeited (3,301 ) Unvested, end of period 1,346,862 Outstanding, end of period 1,346,862 $ 88,489 During the quarter ended June 30, 2015 , the Company granted an aggregate of 31,690 ( 2014 – 97,646 ) restricted shares and restricted share units under the 2007 Plan. The restricted shares and restricted share units granted had weighted average grant date fair values of $2.0 million ( 2014 - $5.1 million ). During the quarter ended June 30, 2015 , the aggregate fair value of restricted shares that vested was $7.8 million ( 2014 - $8.3 million ). For the quarter ended June 30, 2015 , compensation costs recognized in earnings for all restricted shares and restricted share units were $7.6 million ( 2014 - $6.6 million ). At June 30, 2015 , compensation costs not yet recognized related to unvested restricted shares and restricted share units was $34.0 million ( 2014 - $31.8 million ). During the six months ended June 30, 2015 , the Company granted an aggregate of 504,352 ( 2014 – 433,417 ) restricted shares and restricted share units under the 2007 Plan. The restricted shares and restricted share units granted had weighted average grant date fair values of $30.0 million ( 2014 - $22.7 million ). During the six months ended June 30, 2015 , the aggregate fair value of restricted shares and restricted share units that vested was $21.6 million ( 2014 - $18.5 million ). For the six months ended June 30, 2015 , compensation costs recognized in earnings for all restricted shares and restricted share units were $16.9 million ( 2014 - $15.8 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 Endurance Holdings' ordinary shares. For the three and six months ended June 30, 2015 , total expenses related to the Company’s Employee Share Purchase Plan were approximately $79,000 ( 2014 - $55,000 ) and $144,000 ( 2014 - $109,000 ), respectively. The 2005 Employee Share Purchase Plan is scheduled to terminate in accordance with its terms on October 1, 2015. On February 26, 2015, the Compensation Committee of the Board of Directors of Endurance Holdings approved, subject to approval by the Company's shareholders, a new employee share purchase plan ("2015 Employee Share Purchase Plan"). At the Company's Annual General Meeting of Shareholders held on May 20, 2015, the 2015 Employee Share Purchase Plan was approved by the Company's shareholders. 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	6 Months Ended
	Jun. 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 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. 9. Segment reporting, cont'd. The following table provides a summary of segment revenues, results and reserves for losses and loss expenses for the three months ended June 30, 2015 : Three Months Ended June 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 468,866 $ 392,318 $ 861,184 Ceded premiums written (278,567 ) (23,534 ) (302,101 ) Net premiums written 190,299 368,784 559,083 Net premiums earned 201,460 256,675 458,135 Other underwriting income — 1,389 1,389 201,460 258,064 459,524 Expenses Net losses and loss expenses 145,483 93,639 239,122 Acquisition expenses 17,702 67,269 84,971 General and administrative expenses 28,567 26,398 54,965 191,752 187,306 379,058 Underwriting income $ 9,708 $ 70,758 80,466 Net investment income 32,252 Corporate expenses (12,634 ) Net foreign exchange losses (12,981 ) Net realized and unrealized gains 9,680 Net impairment losses recognized in earnings (424 ) Amortization of intangibles (1,579 ) Interest expense (9,062 ) Income before income taxes $ 85,718 Net loss ratio 72.2 % 36.5 % 52.2 % Acquisition expense ratio 8.8 % 26.2 % 18.5 % General and administrative expense ratio 14.2 % 10.3 % 14.8 % (1) Combined ratio 95.2 % 73.0 % 85.5 % Reserve for losses and loss expenses $ 2,157,769 $ 1,675,756 $ 3,833,525 (1) 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 and reserves for losses and loss expenses for the three months ended June 30, 2014 : Three Months Ended June 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 321,526 $ 367,899 $ 689,425 Ceded premiums written (142,488 ) (35,510 ) (177,998 ) Net premiums written 179,038 332,389 511,427 Net premiums earned 218,563 262,975 481,538 Other underwriting loss — (4,824 ) (4,824 ) 218,563 258,151 476,714 Expenses Net losses and loss expenses 149,567 109,629 259,196 Acquisition expenses 15,128 63,473 78,601 General and administrative expenses 35,969 22,343 58,312 200,664 195,445 396,109 Underwriting income $ 17,899 $ 62,706 80,605 Net investment income 39,302 Corporate expenses (28,143 ) Net foreign exchange losses (319 ) Net realized and unrealized gains 3,411 Net impairment losses recognized in earnings (198 ) Amortization of intangibles (1,623 ) Interest expense (9,732 ) Income before income taxes $ 83,303 Net loss ratio 68.5 % 41.7 % 53.8 % Acquisition expense ratio 6.9 % 24.1 % 16.3 % General and administrative expense ratio 16.4 % 8.5 % 18.0 % (1) Combined ratio 91.8 % 74.3 % 88.1 % Reserve for losses and loss expenses $ 2,143,921 $ 1,819,472 $ 3,963,393 (1) 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 June 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 112,012 $ 22,677 $ 80,540 $ 45,826 Casualty and other specialty 146,056 65,302 108,030 56,475 Professional lines 96,736 43,443 74,650 29,846 Property, marine and energy 114,062 58,877 58,306 46,891 Total Insurance 468,866 190,299 321,526 179,038 Reinsurance Catastrophe 139,833 122,305 158,372 123,411 Property 30,560 30,118 42,887 42,886 Casualty 48,132 48,132 30,875 30,868 Professional lines 134,241 134,241 84,117 84,117 Specialty 39,552 33,988 51,648 51,107 Total Reinsurance 392,318 368,784 367,899 332,389 Total $ 861,184 $ 559,083 $ 689,425 $ 511,427 9. Segment reporting, cont'd. The following table provides a summary of the segment revenues and results for the six months ended June 30, 2015 : Six Months Ended June 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 1,205,084 $ 957,532 $ 2,162,616 Ceded premiums written (710,746 ) (127,833 ) (838,579 ) Net premiums written 494,338 829,699 1,324,037 Net premiums earned 337,324 510,670 847,994 Other underwriting income — 3,795 3,795 337,324 514,465 851,789 Expenses Net losses and loss expenses 219,995 191,063 411,058 Acquisition expenses 33,585 133,479 167,064 General and administrative expenses 57,409 52,446 109,855 310,989 376,988 687,977 Underwriting income $ 26,335 $ 137,477 163,812 Net investment income 74,113 Corporate expenses (24,902 ) Net foreign exchange losses (20,533 ) Net realized and unrealized gains 27,869 Net impairment losses recognized in earnings (1,073 ) Amortization of intangibles (3,178 ) Interest expense (18,121 ) Income before income taxes $ 197,987 Net loss ratio 65.2 % 37.4 % 48.5 % Acquisition expense ratio 10.0 % 26.1 % 19.7 % General and administrative expense ratio 17.0 % 10.3 % 15.9 % (1) Combined ratio 92.2 % 73.8 % 84.1 % (1) 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 six months ended June 30, 2014 : Six Months Ended June 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 973,802 $ 873,138 $ 1,846,940 Ceded premiums written (451,737 ) (85,071 ) (536,808 ) Net premiums written 522,065 788,067 1,310,132 Net premiums earned 362,584 515,220 877,804 Other underwriting loss — (6,062 ) (6,062 ) 362,584 509,158 871,742 Expenses Net losses and loss expenses 238,100 197,992 436,092 Acquisition expenses 27,389 123,369 150,758 General and administrative expenses 72,668 45,145 117,813 338,157 366,506 704,663 Underwriting income $ 24,427 $ 142,652 167,079 Net investment income 80,292 Corporate expenses (41,848 ) Net foreign exchange losses (3,283 ) Net realized and unrealized gains 8,283 Net impairment losses recognized in earnings (309 ) Amortization of intangibles (3,240 ) Interest expense (18,783 ) Income before income taxes $ 188,191 Net loss ratio 65.7 % 38.5 % 49.6 % Acquisition expense ratio 7.6 % 23.9 % 17.2 % General and administrative expense ratio 20.0 % 8.7 % 18.2 % (1) Combined ratio 93.3 % 71.1 % 85.0 % (1) 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 six months ended June 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 628,928 $ 225,137 $ 608,434 $ 327,471 Casualty and other specialty 246,738 110,360 175,683 93,288 Professional lines 151,496 67,674 113,430 44,416 Property, marine and energy 177,922 91,167 76,255 56,890 Total Insurance 1,205,084 494,338 973,802 522,065 Reinsurance Catastrophe 264,240 175,765 285,020 202,374 Property 156,260 153,567 209,300 209,208 Casualty 106,230 106,230 115,857 114,260 Professional lines 178,098 178,098 109,736 109,736 Specialty 252,704 216,039 153,225 152,489 Total Reinsurance 957,532 829,699 873,138 788,067 Total $ 2,162,616 $ 1,324,037 $ 1,846,940 $ 1,310,132

Commitments And Contingencies

Commitments And Contingencies	6 Months Ended
	Jun. 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 June 30, 2015 and December 31, 2014 amounted to $942.8 million and $889.1 million , respectively. At June 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 June 30, 2015 and December 31, 2014 , the Company held collateral of $221.0 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 six months ended June 30, 2015 and 2014 , respectively: Broker 2015 2014 Marsh & McLennan Companies, Inc. 26.6 % 22.1 % Aon Benfield 16.2 % 16.0 % Willis Companies 10.5 % 11.8 % Total of largest brokers 53.3 % 49.9 % Letters of credit. As of June 30, 2015 , the Company had issued letters of credit of $192.4 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 June 30, 2015 and December 31, 2014 , the Company had pledged cash and cash equivalents and fixed maturity investments of $151.0 million and $130.6 million , respectively, in favor of certain ceding companies to collateralize obligations. As of June 30, 2015 and December 31, 2014 , the Company had also pledged $219.4 million and $240.0 million of its cash and fixed maturity investments as required to meet collateral obligations for $192.4 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 June 30, 2015 and December 31, 2014 , cash and fixed maturity investments with fair values of $204.0 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 June 30, 2015 and December 31, 2014 . See Note 3. Reinsurance commitments . In the ordinary course of business, the Company periodically enters into reinsurance agreements that include terms which 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 June 30, 2015 are as follows: Twelve months ended June 30, Amount 2016 $ 14,663 2017 14,111 2018 13,811 2019 13,251 2020 13,501 2021 and thereafter 28,570 $ 97,907 Total net lease expense under operating leases for the six months ended June 30, 2015 was $6.4 million ( 2014 – $8.2 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. See Note 11 for a description of the commitments and contingencies related to the Company's acquisition of Montpelier Re Holdings Ltd. ("Montpelier").

Subsequent Event

Subsequent Event	6 Months Ended
	Jun. 30, 2015
Subsequent Events [Abstract]
Subsequent Events [Text Block]	11. Subsequent event 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 100% of the outstanding common shares of Montpelier (the "Merger"). The Merger was completed on July 31, 2015 (the "Closing Date"). Prior to the closing of the Merger, 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. Montpelier, through its operating subsidiaries, was a provider of global property and casualty reinsurance and insurance products. The Merger is expected to increase the Company's breadth of distribution with the addition of a Lloyd's of London platform and a third-party capital insurance and reinsurance investment product business, as well as a property catastrophe business that complements the Company's existing reinsurance portfolio. The Company expects to achieve transaction synergies through costs savings and capital efficiencies. 11. Subsequent event, cont'd. 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 Merger 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 Endurance ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of Endurance ordinary shares. The fair value of the Montpelier restricted share units was determined based on the closing price of Endurance 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 Company incurred certain acquisition and integration costs associated with the Merger prior to the Closing Date. The Company has recorded $3.5 million and $4.5 million of these costs for the three and six months ended June 30, 2015 , respectively. In addition, the Company was contractually obligated to pay investment banking fees of approximately $15.0 million upon closing of the Merger. The Company expects to incur additional costs and expenses associated with the Merger during 2015. Due to the limited time subsequent to the acquisition date, the accounting for the Merger is not yet complete. The Company intends to include amounts recognized as of the acquisition date for the major classes of assets and liabilities assumed, pre-acquisition contingencies and goodwill in the Company's Quarterly Report on Form 10-Q for the third quarter of 2015. The assets and liabilities acquired from Montpelier, the consideration paid to acquire Montpelier, as well as the results of Montpelier's operations are not reflected in the Unaudited Condensed Consolidated Balance Sheet and Unaudited Condensed Consolidated Statements of Income and Comprehensive Income as of and for the three and six months ended June 30, 2015 .

Summary Of Significant Accoun19

Summary Of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
New Accounting Pronouncements, Policy [Policy Text Block]	In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 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 consolidated financial statements. 2. Summary of significant accounting policies, cont'd. 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 consolidated financial statements. 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 consolidated financial statements.

Investments (Policy)

Investments (Policy)	6 Months Ended
	Jun. 30, 2015
Investments [Abstract]
Other Investments	In addition to the Company's fixed maturity, short-term and equity investments, the Company invests in (i) hedge funds and private investment funds that generally invest in senior secured bank debt, high yield credit, distressed debt, distressed real estate, derivatives, and equity long/short strategies ("alternative funds") and (ii) high yield loan funds ("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	Entities that do not have sufficient equity at risk to allow the entity to finance its activities without additional financial support or in which the equity investors, as a group, do not have the characteristics of a controlling financial interest are referred to as variable interest entities ("VIE"). A VIE is consolidated by the variable interest holder that is determined to have the controlling financial interest (primary beneficiary) as a result of having both the power to direct the activities of a VIE that most significantly impact the VIE's economic performance and the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. 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 is involved in the normal course of business with VIEs primarily 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 determined that it was not the primary beneficiary for any of these investments as of June 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 Condensed Consolidated Balance Sheets and any unfunded investment commitments.

Fair Value Measurement (Policy)

Fair Value Measurement (Policy)	6 Months Ended
	Jun. 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. • 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. 4. Fair value measurement, cont'd. • 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 and the 7.0% Senior Notes due July 15, 2034 (the "Senior Notes"). 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 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 and other financial instruments not described above approximated their fair values at June 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)	6 Months Ended
	Jun. 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 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 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 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)	6 Months Ended
	Jun. 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 fixed maturity assets 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 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. 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.
Offsetting of derivatives policy	At June 30, 2015 and December 31, 2014 , none of the Company's derivative instruments were recorded on a net basis in the Condensed Consolidated Balance Sheets.

Stock-Based Employee Compensa24

Stock-Based Employee Compensation And Other Stock Plans (Policies)	6 Months Ended
	Jun. 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 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)	6 Months Ended
	Jun. 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 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.

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2015
Investments [Abstract]
Composition Of Net Investment Income	The components of net investment income for the three and six months ended June 30, 2015 and 2014 are as follows: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Available for sale investments $ 31,705 $ 31,619 $ 63,922 $ 61,946 Other investments 3,570 10,785 15,958 24,327 Cash and cash equivalents 434 511 1,064 1,297 35,709 42,915 $ 80,944 $ 87,570 Investment expenses (3,457 ) (3,613 ) (6,831 ) (7,278 ) Net investment income $ 32,252 $ 39,302 $ 74,113 $ 80,292
Composition of the Investment Portfolio by Investment Type	The following table summarizes the composition of the investment portfolio by investment type at June 30, 2015 and December 31, 2014 : June 30, 2015 December 31, 2014 Type of Investment Fair Value Percentage Fair Value Percentage Fixed maturity investments $ 4,933,776 75.3 % $ 5,092,581 77.1 % Cash and cash equivalents (1) 561,687 8.6 % 632,667 9.6 % Other investments (2) 623,868 9.5 % 541,454 8.2 % Short-term investments 16,366 0.2 % 9,014 0.1 % Equity securities 420,411 6.4 % 331,368 5.0 % Total $ 6,556,108 100.0 % $ 6,607,084 100.0 % (1) Includes net receivable on sales of investments and net payable on purchases of investments. (2) Consists of investments in alternative funds and specialty funds.
Composition Of Fixed Income Portfolio, Including Fixed Maturity Investments And Short-Term Investments, By Investment Ratings	The following table summarizes the composition by investment rating of the fixed maturity and short-term investments at June 30, 2015 and December 31, 2014 . In some cases, where bonds are unrated, the rating of the issuer has been applied. June 30, 2015 December 31, 2014 Ratings (1) Fair Value Percentage Fair Value Percentage U.S. government and agencies securities $ 483,511 9.8 % $ 587,411 11.5 % AAA / Aaa 1,168,977 23.6 % 1,206,252 23.6 % AA / Aa 1,614,866 32.6 % 1,717,343 33.7 % A / A 1,051,739 21.3 % 1,045,301 20.5 % BBB 505,731 10.2 % 427,018 8.4 % Below BBB 105,825 2.1 % 96,244 1.9 % Not rated 19,493 0.4 % 22,026 0.4 % Total $ 4,950,142 100.0 % $ 5,101,595 100.0 % (1) The credit rating for each security reflected above was determined based on the rating assigned to the individual security by Standard & Poor's Financial Services LLC ("Standard & Poor's"). If a rating is not supplied by Standard & Poor's, the equivalent rating supplied by Moody's Investors Service, Inc. ("Moody's"), Fitch Ratings, Inc., or DBRS, Inc. is used.
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 June 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. June 30, 2015 December 31, 2014 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 145,833 $ 146,729 $ 126,921 $ 127,821 Due after one year through five years 1,513,058 1,516,820 1,627,154 1,632,259 Due after five years through ten years 435,077 434,624 474,959 479,138 Due after ten years 48,466 49,940 43,314 46,720 Residential mortgage-backed securities 1,062,261 1,076,732 1,149,536 1,175,006 Commercial mortgage-backed securities 992,858 1,003,518 960,598 979,419 Collateralized loan and debt obligations 325,750 327,642 247,510 248,011 Asset-backed securities 392,416 394,137 411,529 413,221 Total $ 4,915,719 $ 4,950,142 $ 5,041,521 $ 5,101,595
Other Investments	The following table summarizes the composition and redemption restrictions of other investments as of June 30, 2015 and December 31, 2014 : June 30, 2015 Market Value Unfunded Commitments Ineligible for Redemption over next 12 months Alternative funds Hedge funds $ 458,681 $ — $ 81,153 Private investment funds 78,574 53,151 78,574 Total alternative funds 537,255 53,151 159,727 Specialty funds High yield loan funds 86,613 — — Total specialty funds 86,613 — — Total other investments $ 623,868 $ 53,151 $ 159,727 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 six months ended June 30, 2015 and 2014 is as follows: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Gross realized gains on investment sales $ 14,647 $ 7,387 $ 37,313 $ 17,634 Gross realized losses on investment sales (5,058 ) (5,319 ) (9,954 ) (11,303 ) Change in fair value of derivative financial instruments (1) 91 1,343 510 1,952 Net realized and unrealized gains $ 9,680 $ 3,411 $ 27,869 $ 8,283 (1) For additional information on the Company's derivative financial instruments, see Note 7.
Amortized Cost, Fair Value, Gross Unrealized Gains and Losses And Non-Credit Other-Then-Temporary Impairments	The amortized cost, fair value and related gross unrealized gains and losses and non-credit other-than-temporary impairment (“OTTI”) losses on the Company’s securities classified as available for sale at June 30, 2015 and December 31, 2014 are as follows: June 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Non-Credit OTTI (2) Fixed maturity investments U.S. government and agencies securities $ 480,584 $ 5,285 $ (2,358 ) $ 483,511 $ — U.S. state and municipal securities 40,893 164 (520 ) 40,537 — Foreign government securities 156,874 1,293 (534 ) 157,633 — Government guaranteed corporate securities 30,167 434 (32 ) 30,569 — Corporate securities 1,417,548 8,872 (6,923 ) 1,419,497 — Residential mortgage-backed securities 1,062,261 19,786 (5,315 ) 1,076,732 (2,940 ) Commercial mortgage-backed securities 992,858 15,152 (4,492 ) 1,003,518 — Collateralized loan and debt obligations (1) 325,750 2,166 (274 ) 327,642 — Asset-backed securities 392,416 2,069 (348 ) 394,137 — Total fixed maturity investments 4,899,351 55,221 (20,796 ) 4,933,776 (2,940 ) Short-term investments 16,368 — (2 ) 16,366 — Total fixed income investments $ 4,915,719 $ 55,221 $ (20,798 ) $ 4,950,142 $ (2,940 ) Equity securities Equity investments $ 281,005 $ 16,678 $ (6,331 ) $ 291,352 $ — Emerging market debt funds 61,874 — (1,837 ) 60,037 — Convertible funds 46,331 2,240 — 48,571 — Preferred equity investments 13,581 1,993 (46 ) 15,528 — Short-term fixed income fund 4,923 — — 4,923 — Total equity securities $ 407,714 $ 20,911 $ (8,214 ) $ 420,411 $ — (1) Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million . (2) Represents total OTTI recognized in accumulated other comprehensive income. It does not include the change in fair value subsequent to the impairment measurement date. At June 30, 2015 , the gross unrealized loss related to fixed income investments for which a non-credit OTTI was recognized in accumulated other comprehensive income was nil . December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Non-Credit OTTI (2) 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 (3,233 ) Commercial mortgage-backed securities 960,598 21,374 (2,553 ) 979,419 (5 ) 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 (3,238 ) Short-term investments 9,015 — (1 ) 9,014 — Total fixed income investments $ 5,041,521 $ 75,692 $ (15,618 ) $ 5,101,595 $ (3,238 ) 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 . (2) Represents total OTTI recognized in accumulated other comprehensive income. It does not include the change in fair value subsequent to the impairment measurement date. At December 31, 2014 , the gross unrealized loss related to fixed income investments for which a non-credit OTTI was recognized in accumulated other comprehensive income was nil .
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 income at December 31, 2014 . The following tables summarize, for all available for sale securities in an unrealized loss position at June 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 June 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 $ (1,687 ) $ 149,003 $ (671 ) $ 16,995 $ (2,358 ) $ 165,998 U.S. state and municipal securities (520 ) 21,615 — — (520 ) 21,615 Foreign government securities (413 ) 46,557 (121 ) 2,849 (534 ) 49,406 Government guaranteed corporate securities (32 ) 3,300 — — (32 ) 3,300 Corporate securities (6,428 ) 731,507 (495 ) 29,369 (6,923 ) 760,876 Residential mortgage-backed securities (4,014 ) 344,126 (1,301 ) 52,474 (5,315 ) 396,600 Commercial mortgage-backed securities (3,603 ) 324,191 (889 ) 35,150 (4,492 ) 359,341 Collateralized loan and debt obligations (215 ) 95,946 (59 ) 27,618 (274 ) 123,564 Asset-backed securities (208 ) 101,724 (140 ) 12,983 (348 ) 114,707 Total fixed maturity investments (17,120 ) 1,817,969 (3,676 ) 177,438 (20,796 ) 1,995,407 Short-term investments (2 ) 1,506 — — (2 ) 1,506 Total fixed income investments $ (17,122 ) 1,819,475 (3,676 ) 177,438 (20,798 ) 1,996,913 Equity securities Equity investments $ (6,315 ) $ 144,058 $ (16 ) $ 133 $ (6,331 ) $ 144,191 Emerging market debt funds (1,837 ) 60,037 — — (1,837 ) 60,037 Preferred equity investments (46 ) 2,917 — — (46 ) 2,917 Total equity securities $ (8,198 ) $ 207,012 $ (16 ) $ 133 $ (8,214 ) $ 207,145 (1) Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive income at June 30, 2015 .
Analysis Of OTTI	The analysis of OTTI for the three and six months ended June 30, 2015 and 2014 is as follows: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Total other-than-temporary impairment losses $ (424 ) $ (198 ) $ (1,073 ) $ (309 ) Portion of loss recognized in other comprehensive (loss) income — — — — Net impairment losses recognized in earnings $ (424 ) $ (198 ) $ (1,073 ) $ (309 )
Credit Losses Recognized For Available For Sale Investments In Earnings, OTTI Loss Was Recognized In Accumulated Other Comprehensive Income	The following table provides a roll-forward of the amount related to credit losses for the Company's available for sale investments recognized in earnings for which a portion of an OTTI loss was recognized in accumulated other comprehensive income for the three and six months ended June 30, 2015 and 2014 : Three Months Ended Six Months Ended 2015 2014 2015 2014 Beginning balance $ (795 ) $ (1,520 ) $ (838 ) $ (1,553 ) Addition for the amount related to the credit loss for which an other-than-temporary impairment was not previously recognized — — — — Addition for the amount related to the credit loss for which an other-than-temporary impairment was previously recognized — — — — Reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security — — — — Reductions for securities sold during the period 39 79 82 112 Ending balance $ (756 ) $ (1,441 ) $ (756 ) $ (1,441 )

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Schedule Of Available For Sale Investments, Other Investments, Derivative Instruments And Debt Measured On A Recurring Basis	The following table sets forth the Company's available for sale investments, other investments, other assets and liabilities and debt categorized by the level within the hierarchy in which the fair value measurements fall at June 30, 2015 : Fair Value Measurements at June 30, 2015 Total at June 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 $ 483,511 $ 34,235 $ 449,276 $ — U.S. state and municipal securities 40,537 — 40,537 — Foreign government securities 157,633 — 157,633 — Government guaranteed corporate securities 30,569 — 30,569 — Corporate securities 1,419,497 — 1,417,048 2,449 Residential mortgage-backed securities 1,076,732 — 1,076,732 — Commercial mortgage-backed securities 1,003,518 — 1,003,135 383 Collateralized loan and debt obligations 327,642 — 325,767 1,875 Asset-backed securities 394,137 — 394,137 — Total fixed maturity investments 4,933,776 34,235 4,894,834 4,707 Equity securities Equity investments 291,352 157,657 133,695 — Emerging market debt funds 60,037 — 60,037 — Convertible funds 48,571 — 48,571 — Preferred equity investments 15,528 — 15,528 — Short-term fixed income fund 4,923 4,923 — — Total equity securities 420,411 162,580 257,831 — Short-term investments 16,366 — 16,366 — Other investments 623,868 — — 623,868 Other assets (see Note 7) 70,570 — 46,879 23,691 Total assets $ 6,064,991 $ 196,815 $ 5,215,910 $ 652,266 Liabilities Other liabilities (see Note 7) $ 44,383 $ — $ 22,199 $ 22,184 Debt 596,902 — 596,902 — Total liabilities $ 641,285 $ — $ 619,101 $ 22,184 The following table sets forth the Company’s available for sale 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
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 June 30, 2015 and December 31, 2014 : June 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 $ 1,507 Historical Analysis and Simulation Correlation 0 1 Actual Weather curve $ 2,200 $ 10,600 Actual Commodity curve $ — $ 14 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 $ — $ — Actual
Reconciliation Of The Beginning And Ending Balances For All Available For Sale Investments, Other 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 June 30, 2015 and 2014 : Three Months Ended June 30, 2015 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 9,500 $ 575,974 $ 15,223 $ 600,697 $ (17,385 ) Total equity income and realized gains included in earnings — 14,469 — 14,469 — Total equity losses and losses included in earnings (2 ) (10,899 ) — (10,901 ) — Total income included in other underwriting income (loss) — — 3,499 3,499 7,806 Total loss included in other underwriting income (loss) — — (4,152 ) (4,152 ) (3,691 ) Change in unrealized gains included in other comprehensive (loss) income 18 — — 18 — Change in unrealized losses included in other comprehensive (loss) income (64 ) — — (64 ) — Purchases — 63,658 — 63,658 — Issues — — 9,121 9,121 (12,324 ) Sales (96 ) (19,334 ) — (19,430 ) — Settlements — — — — 3,410 Transfers in to Level 3 237 — — 237 — Transfers out of Level 3 (4,886 ) — — (4,886 ) — Level 3, end of period $ 4,707 $ 623,868 $ 23,691 $ 652,266 $ (22,184 ) Three Months Ended June 30, 2014 Fixed maturity investments Other investments Other assets Total assets Other liabilities Level 3, beginning of period $ 8,985 $ 621,914 $ 8,532 $ 639,431 $ (13,448 ) Total equity income and realized gains included in earnings 36 16,286 — 16,322 — Total equity losses and losses included in earnings — (5,501 ) — (5,501 ) — Total income included in other underwriting income (loss) — — 11,241 11,241 12,622 Total loss included in other underwriting income (loss) — — (11,722 ) (11,722 ) (12,177 ) Change in unrealized gains included in other comprehensive (loss) income 89 — — 89 — Change in unrealized losses included in other comprehensive (loss) income (36 ) — — (36 ) — Purchases — 21,867 — 21,867 — Issues — — 2,941 2,941 (5,883 ) Sales (856 ) (5,924 ) — (6,780 ) — Settlements — — — — 8,602 Transfers in to Level 3 2,886 — — 2,886 — Transfers out of Level 3 (1,589 ) — — (1,589 ) — Level 3, end of period $ 9,515 $ 648,642 $ 10,992 $ 669,149 $ (10,284 ) 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 six months ended June 30, 2015 and 2014 : Six Months Ended June 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 35,018 — 35,131 — Total equity losses and losses included in earnings (11 ) (19,060 ) — (19,071 ) — Total income included in other underwriting income (loss) — — 5,595 5,595 20,865 Total loss included in other underwriting income (loss) — — (12,994 ) (12,994 ) (7,220 ) Change in unrealized gains included in other comprehensive (loss) income 24 — — 24 — Change in unrealized losses included in other comprehensive (loss) income (193 ) — — (193 ) — Purchases — 102,979 — 102,979 — Issues — — 12,333 12,333 (18,748 ) Sales (310 ) (36,523 ) — (36,833 ) — Settlements — — (6,858 ) (6,858 ) 18,285 Transfers in to Level 3 1,970 — — 1,970 — Transfers out of Level 3 (9,176 ) — — (9,176 ) — Level 3, end of period $ 4,707 $ 623,868 $ 23,691 $ 652,266 $ (22,184 ) Six Months Ended June 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 53 35,472 — 35,525 — Total equity losses and losses included in earnings (26 ) (11,146 ) — (11,172 ) — Total income included in other underwriting income (loss) — — 15,216 15,216 20,048 Total loss included in other underwriting income (loss) — — (18,610 ) (18,610 ) (16,953 ) Change in unrealized gains included in other comprehensive income (loss) 200 — — 200 — Change in unrealized losses included in other comprehensive income (loss) (151 ) — — (151 ) — Purchases — 26,541 — 26,541 — Issues — — 3,581 3,581 (7,163 ) Sales (1,040 ) (19,703 ) — (20,743 ) — Settlements — — (3,233 ) (3,233 ) 13,353 Transfers in to Level 3 5,003 — — 5,003 — Transfers out of Level 3 (1,852 ) — — (1,852 ) — Level 3, end of period $ 9,515 $ 648,642 $ 10,992 $ 669,149 $ (10,284 )

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 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 share for the three and six months ended June 30, 2015 and 2014 : Three Months Ended Six Months Ended 2015 2014 2015 2014 Numerator: Net income available to common and participating common shareholders $ 76,018 $ 74,975 $ 176,309 $ 171,267 Less amount allocated to participating common shareholders (1) (2,273 ) (2,212 ) (5,237 ) (4,988 ) Net income allocated to common shareholders 73,745 72,763 $ 171,072 $ 166,279 Denominator: Weighted average shares - basic 43,736,541 43,350,911 43,640,052 43,265,200 Share equivalents: Options 150,384 — 148,204 283 Restricted shares and restricted share units 9,796 — 4,370 143 Weighted average shares - diluted 43,896,721 43,350,911 43,792,626 43,265,626 Basic earnings per common share $ 1.69 $ 1.68 $ 3.92 $ 3.84 Diluted earnings per common share $ 1.68 $ 1.68 $ 3.91 $ 3.84 (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 Six Months Ended 2015 2014 2015 2014 Dividends declared per Series A preferred share $ 0.484375 $ 0.484375 $ 0.968750 $ 0.968750 Dividends declared per Series B preferred share $ 0.468750 $ 0.468750 $ 0.937500 $ 0.937500 Dividends declared per common share $ 0.35 $ 0.34 $ 0.70 $ 0.68

Accumulated Other Comprehensi29

Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule Of Accumulated Other Comprehensive Income	The following tables present the changes in accumulated other comprehensive income balances by component for the three months ended June 30, 2015 and 2014 : For the Three Months Ended June 30, 2015 Losses on cash flow hedges Unrealized gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,744 ) $ 110,589 $ (31,086 ) $ 77,759 Other comprehensive (loss) income before reclassifications — (57,671 ) 26,163 (31,508 ) Amounts reclassified from accumulated other comprehensive income (1) 22 (9,308 ) — (9,286 ) Net current period other comprehensive income (loss) 22 (66,979 ) 26,163 (40,794 ) Ending balance $ (1,722 ) $ 43,610 $ (4,923 ) $ 36,965 (1) All amounts are net of tax. For the Three Months Ended June 30, 2014 Losses on cash flow hedges Unrealized gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,832 ) 69,330 $ 21,861 $ 89,359 Other comprehensive income before reclassifications — 39,676 8,998 48,674 Amounts reclassified from accumulated other comprehensive income (1) 22 (2,017 ) — (1,995 ) Net current period other comprehensive income 22 37,659 8,998 46,679 Ending balance $ (1,810 ) $ 106,989 $ 30,859 $ 136,038 (1) All amounts are net of tax. 6. Accumulated other comprehensive income, cont'd. The following tables present the changes in accumulated other comprehensive income balances by component for the six months ended June 30, 2015 and 2014 : For the Six Months Ended June 30, 2015 Losses on cash flow hedges Unrealized 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 — (16,937 ) 2,705 (14,232 ) Amounts reclassified from accumulated other comprehensive income (1) 44 (25,553 ) — (25,509 ) Net current period other comprehensive income (loss) 44 (42,490 ) 2,705 (39,741 ) Ending balance $ (1,722 ) $ 43,610 $ (4,923 ) $ 36,965 (1) All amounts are net of tax. For the Six Months Ended June 30, 2014 Losses on cash flow hedges Unrealized gains on available for sale securities Foreign currency translation adjustments Total Beginning balance $ (1,855 ) $ 45,950 $ 18,636 $ 62,731 Other comprehensive income before reclassifications — 67,341 12,223 79,564 Amounts reclassified from accumulated other comprehensive income (1) 45 (6,302 ) — (6,257 ) Net current period other comprehensive income 45 61,039 12,223 73,307 Ending balance $ (1,810 ) $ 106,989 $ 30,859 $ 136,038 (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 income during the three months ended June 30, 2015 and 2014 : Three Months Ended June 30, 2015 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited 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 $ (9,589 ) Net realized and unrealized gains 424 Net impairment losses recognized in earnings (9,165 ) Total before income taxes (143 ) Income tax benefit $ (9,308 ) Total net of income taxes Three Months Ended June 30, 2014 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited 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 $ (2,068 ) Net realized and unrealized gains 198 Net impairment losses recognized in earnings (1,870 ) Total before income taxes (147 ) Income tax benefit $ (2,017 ) Total net of income taxes The following tables present the significant items reclassified out of accumulated other comprehensive income during the six months ended June 30, 2015 and 2014 : Six Months Ended June 30, 2015 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 44 Interest expense 44 Total before income taxes — Income tax expense $ 44 Total net of income taxes Unrealized gains on available for sale securities $ (27,359 ) Net realized and unrealized gains 1,073 Net impairment losses recognized in earnings (26,286 ) Total before income taxes 733 Income tax expense $ (25,553 ) Total net of income taxes Six Months Ended June 30, 2014 Details about accumulated other comprehensive income components Amount reclassified from accumulated other comprehensive income Affected line item in the Unaudited Condensed Consolidated Statements of Income and Comprehensive Income Losses on cash flow hedges - Debt $ 45 Interest expense 45 Total before income taxes — Income tax expense $ 45 Total net of income taxes Unrealized gains on available for sale securities $ (6,331 ) Net realized and unrealized gains 309 Net impairment losses recognized in earnings (6,022 ) Total before income taxes (280 ) Income tax benefit $ (6,302 ) Total net of income taxes

Derivatives (Tables)

Derivatives (Tables)	6 Months Ended
	Jun. 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 June 30, 2015 and December 31, 2014 are shown below. June 30, 2015 December 31, 2014 Fair Value Notional Principal Amount Fair Value Notional Principal Amount Derivatives recorded in other assets Foreign exchange forward contracts $ 91 $ 24,185 $ 651 $ 42,694 Credit default swaps 27 2,190 — — Interest rate swaps 98 1,900 — — Interest rate futures 3 54,348 7 7,595 TBAs 46,660 44,700 73,231 70,000 Energy and weather contracts 23,691 76,702 25,615 81,624 Total recorded in other assets 70,570 99,504 Derivatives recorded in other liabilities Foreign exchange forward contracts $ 306 $ 26,895 $ 123 $ 20,945 Credit default swaps 1 2,099 — — Interest rate swaps 176 46,000 20 12,549 Interest rate swaptions — — 9 13,100 Interest rate futures 3 9,672 — — TBAs 21,713 20,700 18,820 18,000 Energy and weather contracts 22,184 130,539 35,366 135,050 Total recorded in other liabilities 44,383 54,338 Net derivative asset $ 26,187 $ 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 Condensed Consolidated Statements of Income and Comprehensive Income for derivatives for the three and six months ended June 30, 2015 and 2014 were as follows: Three Months Ended Six Months Ended 2015 2014 2015 2014 Total included in net foreign exchange losses from foreign exchange forward contracts $ (343 ) $ (172 ) $ 1,126 $ (399 ) Interest rate futures (27 ) 115 95 135 Credit default swaps 9 14 9 14 Interest rate swaps 320 (316 ) (235 ) (1,081 ) Interest rate swaptions — (1 ) 28 428 TBAs (211 ) 1,531 613 2,456 Total included in net realized and unrealized gains 91 1,343 510 1,952 Total included in other underwriting income (loss) from energy and weather contracts 3,258 (40 ) 6,042 (299 ) Total gains from derivatives $ 3,006 $ 1,131 $ 7,678 $ 1,254

Stock-Based Employee Compensa31

Stock-Based Employee Compensation And Other Stock Plans (Tables)	6 Months Ended
	Jun. 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 six months ended June 30, 2015 , is presented below: Number of Shares/Units Aggregate Intrinsic Value Unvested, beginning of period 1,290,894 Granted 504,352 Settled (445,083 ) Forfeited (3,301 ) Unvested, end of period 1,346,862 Outstanding, end of period 1,346,862 $ 88,489

Segment Reporting (Tables)

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Summary Of The Segment Revenues, Results And Reserve For Losses And Loss Expenses	The following table provides a summary of segment revenues, results and reserves for losses and loss expenses for the three months ended June 30, 2014 : Three Months Ended June 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 321,526 $ 367,899 $ 689,425 Ceded premiums written (142,488 ) (35,510 ) (177,998 ) Net premiums written 179,038 332,389 511,427 Net premiums earned 218,563 262,975 481,538 Other underwriting loss — (4,824 ) (4,824 ) 218,563 258,151 476,714 Expenses Net losses and loss expenses 149,567 109,629 259,196 Acquisition expenses 15,128 63,473 78,601 General and administrative expenses 35,969 22,343 58,312 200,664 195,445 396,109 Underwriting income $ 17,899 $ 62,706 80,605 Net investment income 39,302 Corporate expenses (28,143 ) Net foreign exchange losses (319 ) Net realized and unrealized gains 3,411 Net impairment losses recognized in earnings (198 ) Amortization of intangibles (1,623 ) Interest expense (9,732 ) Income before income taxes $ 83,303 Net loss ratio 68.5 % 41.7 % 53.8 % Acquisition expense ratio 6.9 % 24.1 % 16.3 % General and administrative expense ratio 16.4 % 8.5 % 18.0 % (1) Combined ratio 91.8 % 74.3 % 88.1 % Reserve for losses and loss expenses $ 2,143,921 $ 1,819,472 $ 3,963,393 (1) General and administrative expense ratio includes general and administrative expenses and corporate expenses. The following table provides a summary of segment revenues, results and reserves for losses and loss expenses for the three months ended June 30, 2015 : Three Months Ended June 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 468,866 $ 392,318 $ 861,184 Ceded premiums written (278,567 ) (23,534 ) (302,101 ) Net premiums written 190,299 368,784 559,083 Net premiums earned 201,460 256,675 458,135 Other underwriting income — 1,389 1,389 201,460 258,064 459,524 Expenses Net losses and loss expenses 145,483 93,639 239,122 Acquisition expenses 17,702 67,269 84,971 General and administrative expenses 28,567 26,398 54,965 191,752 187,306 379,058 Underwriting income $ 9,708 $ 70,758 80,466 Net investment income 32,252 Corporate expenses (12,634 ) Net foreign exchange losses (12,981 ) Net realized and unrealized gains 9,680 Net impairment losses recognized in earnings (424 ) Amortization of intangibles (1,579 ) Interest expense (9,062 ) Income before income taxes $ 85,718 Net loss ratio 72.2 % 36.5 % 52.2 % Acquisition expense ratio 8.8 % 26.2 % 18.5 % General and administrative expense ratio 14.2 % 10.3 % 14.8 % (1) Combined ratio 95.2 % 73.0 % 85.5 % Reserve for losses and loss expenses $ 2,157,769 $ 1,675,756 $ 3,833,525 (1) 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 six months ended June 30, 2015 : Six Months Ended June 30, 2015 Insurance Reinsurance Total Revenues Gross premiums written $ 1,205,084 $ 957,532 $ 2,162,616 Ceded premiums written (710,746 ) (127,833 ) (838,579 ) Net premiums written 494,338 829,699 1,324,037 Net premiums earned 337,324 510,670 847,994 Other underwriting income — 3,795 3,795 337,324 514,465 851,789 Expenses Net losses and loss expenses 219,995 191,063 411,058 Acquisition expenses 33,585 133,479 167,064 General and administrative expenses 57,409 52,446 109,855 310,989 376,988 687,977 Underwriting income $ 26,335 $ 137,477 163,812 Net investment income 74,113 Corporate expenses (24,902 ) Net foreign exchange losses (20,533 ) Net realized and unrealized gains 27,869 Net impairment losses recognized in earnings (1,073 ) Amortization of intangibles (3,178 ) Interest expense (18,121 ) Income before income taxes $ 197,987 Net loss ratio 65.2 % 37.4 % 48.5 % Acquisition expense ratio 10.0 % 26.1 % 19.7 % General and administrative expense ratio 17.0 % 10.3 % 15.9 % (1) Combined ratio 92.2 % 73.8 % 84.1 % (1) 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 six months ended June 30, 2014 : Six Months Ended June 30, 2014 Insurance Reinsurance Total Revenues Gross premiums written $ 973,802 $ 873,138 $ 1,846,940 Ceded premiums written (451,737 ) (85,071 ) (536,808 ) Net premiums written 522,065 788,067 1,310,132 Net premiums earned 362,584 515,220 877,804 Other underwriting loss — (6,062 ) (6,062 ) 362,584 509,158 871,742 Expenses Net losses and loss expenses 238,100 197,992 436,092 Acquisition expenses 27,389 123,369 150,758 General and administrative expenses 72,668 45,145 117,813 338,157 366,506 704,663 Underwriting income $ 24,427 $ 142,652 167,079 Net investment income 80,292 Corporate expenses (41,848 ) Net foreign exchange losses (3,283 ) Net realized and unrealized gains 8,283 Net impairment losses recognized in earnings (309 ) Amortization of intangibles (3,240 ) Interest expense (18,783 ) Income before income taxes $ 188,191 Net loss ratio 65.7 % 38.5 % 49.6 % Acquisition expense ratio 7.6 % 23.9 % 17.2 % General and administrative expense ratio 20.0 % 8.7 % 18.2 % (1) Combined ratio 93.3 % 71.1 % 85.0 % (1) 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 June 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 112,012 $ 22,677 $ 80,540 $ 45,826 Casualty and other specialty 146,056 65,302 108,030 56,475 Professional lines 96,736 43,443 74,650 29,846 Property, marine and energy 114,062 58,877 58,306 46,891 Total Insurance 468,866 190,299 321,526 179,038 Reinsurance Catastrophe 139,833 122,305 158,372 123,411 Property 30,560 30,118 42,887 42,886 Casualty 48,132 48,132 30,875 30,868 Professional lines 134,241 134,241 84,117 84,117 Specialty 39,552 33,988 51,648 51,107 Total Reinsurance 392,318 368,784 367,899 332,389 Total $ 861,184 $ 559,083 $ 689,425 $ 511,427 The following table provides gross and net premiums written by line of business for the six months ended June 30, 2015 and 2014 : Gross premiums written Net premiums written Gross premiums written Net premiums written Business Segment 2015 2015 2014 2014 Insurance Agriculture $ 628,928 $ 225,137 $ 608,434 $ 327,471 Casualty and other specialty 246,738 110,360 175,683 93,288 Professional lines 151,496 67,674 113,430 44,416 Property, marine and energy 177,922 91,167 76,255 56,890 Total Insurance 1,205,084 494,338 973,802 522,065 Reinsurance Catastrophe 264,240 175,765 285,020 202,374 Property 156,260 153,567 209,300 209,208 Casualty 106,230 106,230 115,857 114,260 Professional lines 178,098 178,098 109,736 109,736 Specialty 252,704 216,039 153,225 152,489 Total Reinsurance 957,532 829,699 873,138 788,067 Total $ 2,162,616 $ 1,324,037 $ 1,846,940 $ 1,310,132

Commitments And Contingencies (

Commitments And Contingencies (Tables)	6 Months Ended
	Jun. 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 six months ended June 30, 2015 and 2014 , respectively: Broker 2015 2014 Marsh & McLennan Companies, Inc. 26.6 % 22.1 % Aon Benfield 16.2 % 16.0 % Willis Companies 10.5 % 11.8 % Total of largest brokers 53.3 % 49.9 %
Schedule Of Future Minimum Lease Commitments	Future minimum lease commitments at June 30, 2015 are as follows: Twelve months ended June 30, Amount 2016 $ 14,663 2017 14,111 2018 13,811 2019 13,251 2020 13,501 2021 and thereafter 28,570 $ 97,907

Subsequent Event (Tables)

Subsequent Event (Tables)	6 Months Ended
	Jun. 30, 2015
Subsequent Events [Abstract]
Schedule of Subsequent Events [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 Merger 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 Endurance ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of Endurance ordinary shares. The fair value of the Montpelier restricted share units was determined based on the closing price of Endurance 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.

Investments (Narrative) (Detail

Investments (Narrative) (Details) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2015USD ($)		Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)		Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Investments [Abstract]
Number of available for sale securities in an unrealized loss position	981			981			747
Number of securities in a continuous unrealized loss position for twelve months or greater	92			92			171
Unrealized losses	$ (29,000)	[1]		$ (29,000)	[1]		$ (19,900)	[2]
Unrealized losses, 12 months or greater	(3,700)	[1]		(3,700)	[1]		$ (7,100)	[2]
OTTI losses recognized	$ 424		$ 198	$ 1,073		$ 309
[1]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive income at June 30, 2015.
[2]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive income at December 31, 2014.

Investments (Composition Of Net

Investments (Composition Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Investments [Abstract]
Available for sale investments	$ 31,705	$ 31,619	$ 63,922	$ 61,946
Other investments	3,570	10,785	15,958	24,327
Cash and cash equivalents	434	511	1,064	1,297
Gross investment income	35,709	42,915	80,944	87,570
Investment expenses	(3,457)	(3,613)	(6,831)	(7,278)
Net investment income	$ 32,252	$ 39,302	$ 74,113	$ 80,292

Investments (Summary Of Investm

Investments (Summary Of Investment Portfolio By Type) (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Investment Holdings [Line Items]
Fair value		$ 6,556,108	$ 6,607,084
Percentage		100.00%	100.00%
Fixed Maturities [Member]
Investment Holdings [Line Items]
Fair value		$ 4,933,776	$ 5,092,581
Percentage		75.30%	77.10%
Cash and Cash Equivalents [Member]
Investment Holdings [Line Items]
Fair value	[1]	$ 561,687	$ 632,667
Percentage	[1]	8.60%	9.60%
Other Investments [Member]
Investment Holdings [Line Items]
Fair value	[2]	$ 623,868	$ 541,454
Percentage	[2]	9.50%	8.20%
Short-term Investments [Member]
Investment Holdings [Line Items]
Fair value		$ 16,366	$ 9,014
Percentage		0.20%	0.10%
Equity Securities [Member]
Investment Holdings [Line Items]
Fair value		$ 420,411	$ 331,368
Percentage		6.40%	5.00%
[1]	Includes net receivable on sales of investments and net payable on purchases of investments.
[2]	Consists of investments in alternative funds and specialty funds.

Investments (Composition Of The

Investments (Composition Of The Fixed Income Portfolio By Investment Ratings Assigned By Rating Agencies) (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
US Government and Agencies Securities [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 483,511	$ 587,411
Percentage of fixed income portfolio by investment ratings	[1]	9.80%	11.50%
Standard & Poor's, AAA Rating [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 1,168,977	$ 1,206,252
Percentage of fixed income portfolio by investment ratings	[1]	23.60%	23.60%
Standard & Poor's, AA Rating [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 1,614,866	$ 1,717,343
Percentage of fixed income portfolio by investment ratings	[1]	32.60%	33.70%
Standard & Poor's, A Rating [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 1,051,739	$ 1,045,301
Percentage of fixed income portfolio by investment ratings	[1]	21.30%	20.50%
Standard & Poor's, BBB Rating [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 505,731	$ 427,018
Percentage of fixed income portfolio by investment ratings	[1]	10.20%	8.40%
Standard & Poor's, Below BBB Rating [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 105,825	$ 96,244
Percentage of fixed income portfolio by investment ratings	[1]	2.10%	1.90%
Not Rated [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 19,493	$ 22,026
Percentage of fixed income portfolio by investment ratings	[1]	0.40%	0.40%
Fixed Income Investments [Member]
Investments By Rating [Line Items]
Fair Value of fixed income portfolio by investment ratings	[1]	$ 4,950,142	$ 5,101,595
Percentage of fixed income portfolio by investment ratings	[1]	100.00%	100.00%
[1]	The credit rating for each security reflected above was determined based on the rating assigned to the individual security by Standard & Poor's Financial Services LLC ("Standard & Poor's"). If a rating is not supplied by Standard & Poor's, the equivalent rating supplied by Moody's Investors Service, Inc. ("Moody's"), Fitch Ratings, Inc., or DBRS, Inc. is used.

Investments (Contractual Maturi

Investments (Contractual Maturities Of Fixed Income Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2015		Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Due within one year, amortized cost	$ 145,833		$ 126,921
Due within one year, fair value	146,729		127,821
Due after one year through five years, amortized cost	1,513,058		1,627,154
Due after one year through five years, fair value	1,516,820		1,632,259
Due after five years through ten years, amortized cost	435,077		474,959
Due after five years through ten years, fair value	434,624		479,138
Due after ten years, amortized cost	48,466		43,314
Due after ten years, fair value	49,940		46,720
Fixed income investments, amortized cost	4,899,351		5,032,506
Fixed income investments, fair value	4,933,776		5,092,581
Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
No single maturity date, amortized cost	1,062,261		1,149,536
No single maturity date, fair value	1,076,732		1,175,006
Fixed income investments, amortized cost	1,062,261		1,149,536
Fixed income investments, fair value	1,076,732		1,175,006
Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
No single maturity date, amortized cost	992,858		960,598
No single maturity date, fair value	1,003,518		979,419
Fixed income investments, amortized cost	992,858		960,598
Fixed income investments, fair value	1,003,518		979,419
Collateralized Loan and Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
No single maturity date, amortized cost	325,750		247,510
No single maturity date, fair value	327,642		248,011
Fixed income investments, amortized cost	325,750	[1]	247,510	[2]
Fixed income investments, fair value	327,642	[1]	248,011	[2]
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
No single maturity date, amortized cost	392,416		411,529
No single maturity date, fair value	394,137		413,221
Fixed income investments, amortized cost	392,416		411,529
Fixed income investments, fair value	394,137		413,221
Fixed Income Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	4,915,719		5,041,521
Fixed income investments, fair value	$ 4,950,142		$ 5,101,595
[1]	Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million.
[2]	Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million.

Investments (Other Investments)

Investments (Other Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 623,868	$ 541,454
Commitments under investment fund classified within other investments	53,151	70,542
Prohibited amount under redemption requests over the next 12 months	159,727	85,244
Alternative Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	537,255	485,944
Commitments under investment fund classified within other investments	53,151	70,542
Prohibited amount under redemption requests over the next 12 months	159,727	85,244
Hedge Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	458,681	411,280
Commitments under investment fund classified within other investments	0	0
Prohibited amount under redemption requests over the next 12 months	81,153	10,580
Private Equity Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	78,574	74,664
Commitments under investment fund classified within other investments	53,151	70,542
Prohibited amount under redemption requests over the next 12 months	78,574	74,664
Specialty Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	86,613	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 [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	86,613	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	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Other investments, invested amount	$ 452,700	$ 387,200
Other investments, market value	623,868	541,454
Alternative Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 537,255	485,944
Hedge Funds [Member]
Schedule of Equity Method Investments [Line Items]
Estimated liquidation, percentage in next 12 months	82.30%
Other investments, market value	$ 458,681	411,280
Hedge Funds [Member] | Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated notice period, in days	90 days
Hedge Funds [Member] | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated notice period, in days	30 days
Private Equity Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 78,574	74,664
Private Equity Funds [Member] | Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated remaining liquidation period in years	10 years
Private Equity Funds [Member] | Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated remaining liquidation period in years	5 years
Specialty Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 86,613	55,510
High Yield Loan Funds [Member]
Schedule of Equity Method Investments [Line Items]
Other investments, market value	$ 86,613	$ 55,510
High Yield Loan Funds [Member] | Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Estimated notice period, in days	90 days
High Yield Loan Funds [Member] | 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		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Investments [Abstract]
Gross realized gains on investment sales		$ 14,647	$ 7,387	$ 37,313	$ 17,634
Gross realized losses on investment sales		(5,058)	(5,319)	(9,954)	(11,303)
Change in fair value of derivative financial instruments	[1]	91	1,343	510	1,952
Net realized and unrealized gains		$ 9,680	$ 3,411	$ 27,869	$ 8,283
[1]	For additional information on the Company's derivative financial instruments, see Note 7.

Investments (Amortized Cost, Fa

Investments (Amortized Cost, Fair Value, Gross Unrealized Gains And Losses And Non-Credit Other-Than-Temporary Impairment) (Details) - USD ($)	Jun. 30, 2015		Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	$ 4,899,351,000		$ 5,032,506,000
Fixed income investments, fair value	4,933,776,000		5,092,581,000
Equity securities, cost	407,714,000		303,922,000
Equity securities, fair value	420,411,000		331,368,000
Gross unrealized loss related to securities, non-credit OTTI	0		0
US Government and Agencies Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	480,584,000		582,970,000
Fixed income investments, gross unrealized gains	5,285,000		6,471,000
Fixed income investments, gross unrealized losses	(2,358,000)		(2,030,000)
Fixed income investments, fair value	483,511,000		587,411,000
Non-Credit OTTI	0	[1]	0	[2]
US State and Municipal Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	40,893,000		39,340,000
Fixed income investments, gross unrealized gains	164,000		191,000
Fixed income investments, gross unrealized losses	(520,000)		(118,000)
Fixed income investments, fair value	40,537,000		39,413,000
Non-Credit OTTI	0	[1]	0	[2]
Foreign Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	156,874,000		239,217,000
Fixed income investments, gross unrealized gains	1,293,000		2,983,000
Fixed income investments, gross unrealized losses	(534,000)		(1,664,000)
Fixed income investments, fair value	157,633,000		240,536,000
Non-Credit OTTI	0	[1]	0	[2]
Government Guaranteed Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	30,167,000		47,436,000
Fixed income investments, gross unrealized gains	434,000		675,000
Fixed income investments, gross unrealized losses	(32,000)		(9,000)
Fixed income investments, fair value	30,569,000		48,102,000
Non-Credit OTTI	0	[1]	0	[2]
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	1,417,548,000		1,354,370,000
Fixed income investments, gross unrealized gains	8,872,000		12,742,000
Fixed income investments, gross unrealized losses	(6,923,000)		(5,650,000)
Fixed income investments, fair value	1,419,497,000		1,361,462,000
Non-Credit OTTI	0	[1]	0	[2]
Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	1,062,261,000		1,149,536,000
Fixed income investments, gross unrealized gains	19,786,000		27,542,000
Fixed income investments, gross unrealized losses	(5,315,000)		(2,072,000)
Fixed income investments, fair value	1,076,732,000		1,175,006,000
Non-Credit OTTI	(2,940,000)	[1]	(3,233,000)	[2]
Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	992,858,000		960,598,000
Fixed income investments, gross unrealized gains	15,152,000		21,374,000
Fixed income investments, gross unrealized losses	(4,492,000)		(2,553,000)
Fixed income investments, fair value	1,003,518,000		979,419,000
Non-Credit OTTI	0	[1]	(5,000)	[2]
Collateralized Loan and Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	325,750,000	[3]	247,510,000	[4]
Fixed income investments, gross unrealized gains	2,166,000	[3]	1,449,000	[4]
Fixed income investments, gross unrealized losses	(274,000)	[3]	(948,000)	[4]
Fixed income investments, fair value	327,642,000	[3]	248,011,000	[4]
Non-Credit OTTI	0	[1],[3]	0	[2],[4]
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	392,416,000		411,529,000
Fixed income investments, gross unrealized gains	2,069,000		2,265,000
Fixed income investments, gross unrealized losses	(348,000)		(573,000)
Fixed income investments, fair value	394,137,000		413,221,000
Non-Credit OTTI	0	[1]	0	[2]
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	4,899,351,000		5,032,506,000
Fixed income investments, gross unrealized gains	55,221,000		75,692,000
Fixed income investments, gross unrealized losses	(20,796,000)		(15,617,000)
Fixed income investments, fair value	4,933,776,000		5,092,581,000
Non-Credit OTTI	(2,940,000)	[1]	(3,238,000)	[2]
Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	16,368,000		9,015,000
Fixed income investments, gross unrealized gains	0		0
Fixed income investments, gross unrealized losses	(2,000)		(1,000)
Fixed income investments, fair value	16,366,000		9,014,000
Non-Credit OTTI	0	[1]	0	[2]
Fixed Income Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, amortized cost	4,915,719,000		5,041,521,000
Fixed income investments, gross unrealized gains	55,221,000		75,692,000
Fixed income investments, gross unrealized losses	(20,798,000)		(15,618,000)
Fixed income investments, fair value	4,950,142,000		5,101,595,000
Non-Credit OTTI	(2,940,000)	[1]	(3,238,000)	[2]
Equity Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	281,005,000		176,167,000
Equity securities, gross unrealized gains	16,678,000		29,660,000
Equity securities, gross unrealized losses	(6,331,000)		(3,292,000)
Equity securities, fair value	291,352,000		202,535,000
Non-Credit OTTI	0	[1]	0	[2]
Emerging Market Debt Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	61,874,000		60,826,000
Equity securities, gross unrealized gains	0		0
Equity securities, gross unrealized losses	(1,837,000)		(676,000)
Equity securities, fair value	60,037,000		60,150,000
Non-Credit OTTI	0	[1]	0	[2]
Convertible Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	46,331,000		46,331,000
Equity securities, gross unrealized gains	2,240,000		0
Equity securities, gross unrealized losses	0		(220,000)
Equity securities, fair value	48,571,000		46,111,000
Non-Credit OTTI	0	[1]	0	[2]
Preferred Equity Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	13,581,000		13,858,000
Equity securities, gross unrealized gains	1,993,000		2,022,000
Equity securities, gross unrealized losses	(46,000)		(44,000)
Equity securities, fair value	15,528,000		15,836,000
Non-Credit OTTI	0	[1]	0	[2]
Short-term Fixed Income Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	4,923,000		6,740,000
Equity securities, gross unrealized gains	0		0
Equity securities, gross unrealized losses	0		(4,000)
Equity securities, fair value	4,923,000		6,736,000
Non-Credit OTTI	0	[1]	0	[2]
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, cost	407,714,000		303,922,000
Equity securities, gross unrealized gains	20,911,000		31,682,000
Equity securities, gross unrealized losses	(8,214,000)		(4,236,000)
Equity securities, fair value	420,411,000		331,368,000
Non-Credit OTTI	0	[1]	0	[2]
Collateralized Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income investments, fair value	$ 15,200,000		$ 15,200,000
[1]	Represents total OTTI recognized in accumulated other comprehensive income. It does not include the change in fair value subsequent to the impairment measurement date. At June 30, 2015, the gross unrealized loss related to fixed income investments for which a non-credit OTTI was recognized in accumulated other comprehensive income was nil.
[2]	Represents total OTTI recognized in accumulated other comprehensive income. It does not include the change in fair value subsequent to the impairment measurement date. At December 31, 2014, the gross unrealized loss related to fixed income investments for which a non-credit OTTI was recognized in accumulated other comprehensive income was nil.
[3]	Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million.
[4]	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		Jun. 30, 2015		Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, 12 months or greater		$ (3,700)	[1]	$ (7,100)	[2]
Unrealized losses		(29,000)	[1]	(19,900)	[2]
US Government and Agencies Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(1,687)	[1]	(481)	[2]
Fair value, less than 12 months		149,003		155,350
Unrealized losses, 12 months or greater		(671)	[1]	(1,549)	[2]
Fair value, 12 months or greater		16,995		45,993
Unrealized losses		(2,358)	[1]	(2,030)	[2]
Fair value		165,998		201,343
US State and Municipal Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(520)	[1]	(47)	[2]
Fair value, less than 12 months		21,615		3,295
Unrealized losses, 12 months or greater		0	[1]	(71)	[2]
Fair value, 12 months or greater		0		6,841
Unrealized losses		(520)	[1]	(118)	[2]
Fair value		21,615		10,136
Foreign Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(413)	[1]	(1,378)	[2]
Fair value, less than 12 months		46,557		37,904
Unrealized losses, 12 months or greater		(121)	[1]	(286)	[2]
Fair value, 12 months or greater		2,849		4,306
Unrealized losses		(534)	[1]	(1,664)	[2]
Fair value		49,406		42,210
Government Guaranteed Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(32)	[1]	(9)	[2]
Fair value, less than 12 months		3,300		4,598
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(32)	[1]	(9)	[2]
Fair value		3,300		4,598
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(6,428)	[1]	(4,023)	[2]
Fair value, less than 12 months		731,507		533,139
Unrealized losses, 12 months or greater		(495)	[1]	(1,627)	[2]
Fair value, 12 months or greater		29,369		84,278
Unrealized losses		(6,923)	[1]	(5,650)	[2]
Fair value		760,876		617,417
Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(4,014)	[1]	(260)	[2]
Fair value, less than 12 months		344,126		62,832
Unrealized losses, 12 months or greater		(1,301)	[1]	(1,812)	[2]
Fair value, 12 months or greater		52,474		108,899
Unrealized losses		(5,315)	[1]	(2,072)	[2]
Fair value		396,600		171,731
Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(3,603)	[1]	(1,068)	[2]
Fair value, less than 12 months		324,191		180,222
Unrealized losses, 12 months or greater		(889)	[1]	(1,485)	[2]
Fair value, 12 months or greater		35,150		78,412
Unrealized losses		(4,492)	[1]	(2,553)	[2]
Fair value		359,341		258,634
Collateralized Loan and Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(215)	[1]	(876)	[2]
Fair value, less than 12 months		95,946		176,439
Unrealized losses, 12 months or greater		(59)	[1]	(72)	[2]
Fair value, 12 months or greater		27,618		6,491
Unrealized losses		(274)	[1]	(948)	[2]
Fair value		123,564		182,930
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(208)	[1]	(415)	[2]
Fair value, less than 12 months		101,724		199,205
Unrealized losses, 12 months or greater		(140)	[1]	(158)	[2]
Fair value, 12 months or greater		12,983		19,095
Unrealized losses		(348)	[1]	(573)	[2]
Fair value		114,707		218,300
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(17,120)	[1]	(8,557)	[2]
Fair value, less than 12 months		1,817,969		1,352,984
Unrealized losses, 12 months or greater		(3,676)	[1]	(7,060)	[2]
Fair value, 12 months or greater		177,438		354,315
Unrealized losses		(20,796)	[1]	(15,617)	[2]
Fair value		1,995,407		1,707,299
Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(2)	[1]	(1)	[2]
Fair value, less than 12 months		1,506		1,953
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(2)	[1]	(1)	[2]
Fair value		1,506		1,953
Fixed Income Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(17,122)	[1]	(8,558)	[2]
Fair value, less than 12 months		1,819,475		1,354,937
Unrealized losses, 12 months or greater		(3,676)	[1]	(7,060)	[2]
Fair value, 12 months or greater		177,438		354,315
Unrealized losses		(20,798)	[1]	(15,618)	[2]
Fair value		1,996,913		1,709,252
Equity Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(6,315)	[1]	(3,292)	[2]
Fair value, less than 12 months		144,058		53,591
Unrealized losses, 12 months or greater		(16)	[1]	0	[2]
Fair value, 12 months or greater		133		0
Unrealized losses		(6,331)	[1]	(3,292)	[2]
Fair value		144,191		53,591
Emerging Market Debt Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(1,837)	[1]	(676)	[2]
Fair value, less than 12 months		60,037		60,150
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(1,837)	[1]	(676)	[2]
Fair value		60,037		60,150
Convertible Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months	[2]			(220)
Fair value, less than 12 months				46,111
Unrealized losses, 12 months or greater	[2]			0
Fair value, 12 months or greater				0
Unrealized losses	[2]			(220)
Fair value				46,111
Preferred Equity Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(46)	[1]	(44)	[2]
Fair value, less than 12 months		2,917		4,449
Unrealized losses, 12 months or greater		0	[1]	0	[2]
Fair value, 12 months or greater		0		0
Unrealized losses		(46)	[1]	(44)	[2]
Fair value		2,917		4,449
Short-term Fixed Income Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months	[2]			(4)
Fair value, less than 12 months				6,736
Unrealized losses, 12 months or greater	[2]			0
Fair value, 12 months or greater				0
Unrealized losses	[2]			(4)
Fair value				6,736
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized losses, less than 12 months		(8,198)	[1]	(4,236)	[2]
Fair value, less than 12 months		207,012		171,037
Unrealized losses, 12 months or greater		(16)	[1]	0	[2]
Fair value, 12 months or greater		133		0
Unrealized losses		(8,214)	[1]	(4,236)	[2]
Fair value		$ 207,145		$ 171,037
[1]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive income at June 30, 2015.
[2]	Gross unrealized losses include unrealized losses on non-OTTI and non-credit OTTI securities recognized in accumulated other comprehensive income at December 31, 2014.

Investments (Analysis Of OTTI)

Investments (Analysis Of OTTI) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Investments [Abstract]
Total other-than-temporary impairment losses	$ (424)	$ (198)	$ (1,073)	$ (309)
Portion of loss recognized in other comprehensive (loss) income	0	0	0	0
Net impairment losses recognized in earnings	$ (424)	$ (198)	$ (1,073)	$ (309)

Investments (Credit Losses Roll

Investments (Credit Losses Rollforward) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Investments [Abstract]
Beginning balance	$ (795)	$ (1,520)	$ (838)	$ (1,553)
Addition for the amount related to the credit loss for which an other-than-temporary impairment was not previously recognized	0	0	0	0
Addition for the amount related to the credit loss for which an other-than-temporary impairment was previously recognized	0	0	0	0
Reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security	0	0	0	0
Reductions for securities sold during the period	39	79	82	112
Ending balance	$ (756)	$ (1,441)	$ (756)	$ (1,441)

Fair Value Measurement (Narrati

Fair Value Measurement (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers in to Level 3	$ 237,000	$ 2,886,000	$ 1,970,000	$ 5,003,000
Transfers out of Level 3	(4,886,000)	(1,589,000)	(9,176,000)	(1,852,000)
Net impairment losses recognized in earnings	424,000	198,000	1,073,000	309,000
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers in to Level 3	200,000		2,000,000
Transfers out of Level 3	$ (4,900,000)		$ (9,200,000)
Percentage of level 3 assets	10.80%		10.80%		9.50%
Net impairment losses recognized in earnings	$ 0	$ 0	$ 0	$ 0

Fair Value Measurement (Schedul

Fair Value Measurement (Schedule Of Available For Sale Investments, Other Investments, Derivative Instruments And Debt) (Details) - USD ($) $ in Thousands	Jun. 30, 2015		Dec. 31, 2014
Assets
Fixed maturity investments	$ 4,933,776		$ 5,092,581
Short-term investments	16,366		9,014
Equity securities	420,411		331,368
Other investments	623,868		541,454
Other assets (see Note 7)	70,570		99,504
Total assets	6,064,991		6,073,921
Liabilities
Other liabilities (see Note 7)	44,383		54,338
Debt	596,902		623,740
Total liabilities	641,285		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	196,815		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	16,366		9,014
Other investments	0		0
Other assets (see Note 7)	46,879		73,889
Total assets	5,215,910		5,244,242
Liabilities
Other liabilities (see Note 7)	22,199		18,972
Debt	596,902		623,740
Total liabilities	619,101		642,712
Fair Value, Inputs, Level 3 [Member]
Assets
Short-term investments	0		0
Other investments	623,868		541,454
Other assets (see Note 7)	23,691		25,615
Total assets	652,266		579,359
Liabilities
Other liabilities (see Note 7)	22,184		35,366
Debt	0		0
Total liabilities	22,184		35,366
US Government and Agencies Securities [Member]
Assets
Fixed maturity investments	483,511		587,411
US Government and Agencies Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	34,235		105,121
US Government and Agencies Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	449,276		482,290
US Government and Agencies Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0		0
US State and Municipal Debt Securities [Member]
Assets
Fixed maturity investments	40,537		39,413
US State and Municipal Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
US State and Municipal Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	40,537		39,413
US State and Municipal Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0		0
Foreign Government Securities [Member]
Assets
Fixed maturity investments	157,633		240,536
Foreign Government Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
Foreign Government Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	157,633		240,536
Foreign Government Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0		0
Government Guaranteed Corporate Securities [Member]
Assets
Fixed maturity investments	30,569		48,102
Government Guaranteed Corporate Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
Government Guaranteed Corporate Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	30,569		48,102
Government Guaranteed Corporate Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0		0
Corporate Securities [Member]
Assets
Fixed maturity investments	1,419,497		1,361,462
Corporate Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
Corporate Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	1,417,048		1,358,960
Corporate Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	2,449		2,502
Residential Mortgage Backed Securities [Member]
Assets
Fixed maturity investments	1,076,732		1,175,006
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	1,076,732		1,174,997
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0		9
Commercial Mortgage Backed Securities [Member]
Assets
Fixed maturity investments	1,003,518		979,419
Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	1,003,135		974,602
Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	383		4,817
Collateralized Loan and Debt Obligations [Member]
Assets
Fixed maturity investments	327,642	[1]	248,011	[2]
Collateralized Loan and Debt Obligations [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
Collateralized Loan and Debt Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	325,767		246,042
Collateralized Loan and Debt Obligations [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	1,875		1,969
Asset-backed Securities [Member]
Assets
Fixed maturity investments	394,137		413,221
Asset-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	0		0
Asset-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	394,137		410,228
Asset-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	0		2,993
Fixed Maturities [Member]
Assets
Fixed maturity investments	4,933,776		5,092,581
Fixed Maturities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Fixed maturity investments	34,235		105,121
Fixed Maturities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Fixed maturity investments	4,894,834		4,975,170
Fixed Maturities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Fixed maturity investments	4,707		12,290
Equity Investments [Member]
Assets
Equity securities	291,352		202,535
Equity Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	157,657		138,463
Equity Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	133,695		64,072
Equity Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0		0
Emerging Market Debt Funds [Member]
Assets
Equity securities	60,037		60,150
Emerging Market Debt Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	0		0
Emerging Market Debt Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	60,037		60,150
Emerging Market Debt Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0		0
Convertible Funds [Member]
Assets
Equity securities	48,571		46,111
Convertible Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	0		0
Convertible Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	48,571		46,111
Convertible Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0		0
Preferred Equity Investments [Member]
Assets
Equity securities	15,528		15,836
Preferred Equity Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	0		0
Preferred Equity Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	15,528		15,836
Preferred Equity Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0		0
Short-term Fixed Income Fund [Member]
Assets
Equity securities	4,923		6,736
Short-term Fixed Income Fund [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	4,923		6,736
Short-term Fixed Income Fund [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	0		0
Short-term Fixed Income Fund [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	0		0
Equity Securities [Member]
Assets
Equity securities	420,411		331,368
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Equity securities	162,580		145,199
Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Equity securities	257,831		186,169
Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Equity securities	$ 0		$ 0
[1]	Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million.
[2]	Balances include amounts related to collateralized debt obligations held with total fair values of $15.2 million.

Fair Value Measurement (Quantit

Fair Value Measurement (Quantitative Information Used As Level 3 Inputs) (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2015USD ($)	Dec. 31, 2014USD ($)
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Net weather and energy related derivative assets and liabilities	$ 26,187,000	$ 45,166,000
Derivatives recorded in other assets, fair value	70,570,000	99,504,000
Derivatives recorded in other liabilities, fair value	44,383,000	54,338,000
Energy Related Derivative [Member]
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]
Derivatives recorded in other assets, fair value	23,691,000	25,615,000
Derivatives recorded in other liabilities, fair value	22,184,000	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	1,507,000	(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	23,691,000	25,615,000
Derivatives recorded in other liabilities, fair value	$ 22,184,000	$ 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	$ 14,000	$ 0
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		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	$ 600,697	$ 639,431	$ 579,359	$ 638,844
Total equity income and realized gains included in earnings	14,469	16,322	35,131	35,525
Total equity losses and losses included in earnings	(10,901)	(5,501)	(19,071)	(11,172)
Total income included in other underwriting income (loss)	3,499	11,241	5,595	15,216
Total loss included in other underwriting income (loss)	(4,152)	(11,722)	(12,994)	(18,610)
Change in unrealized gains included in other comprehensive (loss) income	18	89	24	200
Change in unrealized losses included in other comprehensive (loss) income	(64)	(36)	(193)	(151)
Purchases	63,658	21,867	102,979	26,541
Issues	9,121	2,941	12,333	3,581
Sales	(19,430)	(6,780)	(36,833)	(20,743)
Settlements	0	0	(6,858)	(3,233)
Transfers in to Level 3	237	2,886	1,970	5,003
Transfers out of Level 3	(4,886)	(1,589)	(9,176)	(1,852)
Level 3, end of period	652,266	669,149	652,266	669,149
Fixed Maturity Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	9,500	8,985	12,290	7,328
Total equity income and realized gains included in earnings	0	36	113	53
Total equity losses and losses included in earnings	(2)	0	(11)	(26)
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	18	89	24	200
Change in unrealized losses included in other comprehensive (loss) income	(64)	(36)	(193)	(151)
Purchases	0	0	0	0
Issues	0	0	0	0
Sales	(96)	(856)	(310)	(1,040)
Settlements	0	0	0	0
Transfers in to Level 3	237	2,886	1,970	5,003
Transfers out of Level 3	(4,886)	(1,589)	(9,176)	(1,852)
Level 3, end of period	4,707	9,515	4,707	9,515
Other Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	575,974	621,914	541,454	617,478
Total equity income and realized gains included in earnings	14,469	16,286	35,018	35,472
Total equity losses and losses included in earnings	(10,899)	(5,501)	(19,060)	(11,146)
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	63,658	21,867	102,979	26,541
Issues	0	0	0	0
Sales	(19,334)	(5,924)	(36,523)	(19,703)
Settlements	0	0	0	0
Transfers in to Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Level 3, end of period	623,868	648,642	623,868	648,642
Other Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	15,223	8,532	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)	3,499	11,241	5,595	15,216
Total loss included in other underwriting income (loss)	(4,152)	(11,722)	(12,994)	(18,610)
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	0	0	0	0
Issues	9,121	2,941	12,333	3,581
Sales	0	0	0	0
Settlements	0	0	(6,858)	(3,233)
Transfers in to Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Level 3, end of period	23,691	10,992	23,691	10,992
Other Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of period	(17,385)	(13,448)	(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)	7,806	12,622	20,865	20,048
Total loss included in other underwriting income (loss)	(3,691)	(12,177)	(7,220)	(16,953)
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	0	0	0	0
Issues	(12,324)	(5,883)	(18,748)	(7,163)
Sales	0	0	0	0
Settlements	3,410	8,602	18,285	13,353
Transfers in to Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Level 3, end of period	$ (22,184)	$ (10,284)	$ (22,184)	$ (10,284)

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		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net income available to common and participating common shareholders		$ 76,018	$ 74,975	$ 176,309	$ 171,267
Less amount allocated to participating common shareholders	[1]	(2,273)	(2,212)	(5,237)	(4,988)
Net income allocated to common shareholders		$ 73,745	$ 72,763	$ 171,072	$ 166,279
Weighted average shares - basic		43,736,541	43,350,911	43,640,052	43,265,200
Weighted average shares - diluted		43,896,721	43,350,911	43,792,626	43,265,626
Basic earnings per common share		$ 1.69	$ 1.68	$ 3.92	$ 3.84
Diluted earnings per common share		$ 1.68	$ 1.68	$ 3.91	$ 3.84
Employee Stock Option [Member]
Share equivalents		150,384	0	148,204	283
Restricted Stock [Member]
Share equivalents		9,796	0	4,370	143
[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		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Dividends Declared [Line Items]
Dividends declared per common share	$ 0.35	$ 0.34	$ 0.70	$ 0.68
Series A Preferred Stock [Member]
Dividends Declared [Line Items]
Dividends declared per preferred share	0.484375	0.484375	0.968750	0.968750
Series B Preferred Stock [Member]
Dividends Declared [Line Items]
Dividends declared per preferred share	$ 0.468750	$ 0.468750	$ 0.937500	$ 0.937500

Accumulated Other Comprehensi53

Accumulated Other Comprehensive Income (Schedule Of Changes In Accumulated Other Comprehensive Income By Component) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive Income [Line Items]
Beginning balance		$ 77,759	$ 89,359	$ 76,706	$ 62,731
Other comprehensive (loss) income before reclassifications		(31,508)	48,674	(14,232)	79,564
Amounts reclassified from accumulated other comprehensive income	[1]	(9,286)	(1,995)	(25,509)	(6,257)
Other comprehensive (loss) income		(40,794)	46,679	(39,741)	73,307
Ending balance		36,965	136,038	36,965	136,038
Gains and losses on cash flow hedges [Member]
Accumulated Other Comprehensive Income [Line Items]
Beginning balance		(1,744)	(1,832)	(1,766)	(1,855)
Other comprehensive (loss) income before reclassifications		0	0	0	0
Amounts reclassified from accumulated other comprehensive income	[1]	22	22	44	45
Other comprehensive (loss) income		22	22	44	45
Ending balance		(1,722)	(1,810)	(1,722)	(1,810)
Unrealized gains on available for sale securities [Member]
Accumulated Other Comprehensive Income [Line Items]
Beginning balance		110,589	69,330	86,100	45,950
Other comprehensive (loss) income before reclassifications		(57,671)	39,676	(16,937)	67,341
Amounts reclassified from accumulated other comprehensive income	[1]	(9,308)	(2,017)	(25,553)	(6,302)
Other comprehensive (loss) income		(66,979)	37,659	(42,490)	61,039
Ending balance		43,610	106,989	43,610	106,989
Foreign currency translation adjustments [Member]
Accumulated Other Comprehensive Income [Line Items]
Beginning balance		(31,086)	21,861	(7,628)	18,636
Other comprehensive (loss) income before reclassifications		26,163	8,998	2,705	12,223
Amounts reclassified from accumulated other comprehensive income	[1]	0	0	0	0
Other comprehensive (loss) income		26,163	8,998	2,705	12,223
Ending balance		$ (4,923)	$ 30,859	$ (4,923)	$ 30,859
[1]	All amounts are net of tax.

Accumulated Other Comprehensi54

Accumulated Other Comprehensive Income (Schedule Of Reclassifications Out Of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 9,062	$ 9,732	$ 18,121	$ 18,783
Net realized and unrealized gains	(9,680)	(3,411)	(27,869)	(8,283)
Net impairment losses recognized in earnings	424	198	1,073	309
Total before income taxes	(85,718)	(83,303)	(197,987)	(188,191)
Income tax expense (benefit)	1,512	140	5,302	548
Total net of income taxes	(84,206)	(83,163)	(192,685)	(187,643)
Gains and losses on cash flow hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	22	22	44	45
Total before income taxes	22	22	44	45
Income tax expense (benefit)	0	0	0	0
Total net of income taxes	22	22	44	45
Unrealized gains on available for sale securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net realized and unrealized gains	(9,589)	(2,068)	(27,359)	(6,331)
Net impairment losses recognized in earnings	424	198	1,073	309
Total before income taxes	(9,165)	(1,870)	(26,286)	(6,022)
Income tax expense (benefit)	(143)	(147)	733	(280)
Total net of income taxes	$ (9,308)	$ (2,017)	$ (25,553)	$ (6,302)

Derivatives (Schedule Of Deriva

Derivatives (Schedule Of Derivative Fair Value And Notional Amount) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	$ 70,570	$ 99,504
Derivatives recorded in other liabilities, fair value	44,383	54,338
Net derivative asset, fair value	26,187	45,166
Derivative assets traded under master netting agreements	70,600	99,500
Derivative liabilities traded under master netting agreements	$ 44,400	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	$ 91	651
Derivatives recorded in other liabilities, fair value	306	123
Derivatives recorded in other assets, notional principal amount	24,185	42,694
Derivatives recorded in other liabilities, notional principal amount	26,895	20,945
Credit Default Swap [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	27	0
Derivatives recorded in other liabilities, fair value	1	0
Derivatives recorded in other assets, notional principal amount	2,190	0
Derivatives recorded in other liabilities, notional principal amount	2,099	0
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	98	0
Derivatives recorded in other liabilities, fair value	176	20
Derivatives recorded in other assets, notional principal amount	1,900	0
Derivatives recorded in other liabilities, notional principal amount	46,000	12,549
Interest Rate Future [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	3	7
Derivatives recorded in other liabilities, fair value	3	0
Derivatives recorded in other assets, notional principal amount	54,348	7,595
Derivatives recorded in other liabilities, notional principal amount	9,672	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
TBA [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	46,660	73,231
Derivatives recorded in other liabilities, fair value	21,713	18,820
Derivatives recorded in other assets, notional principal amount	44,700	70,000
Derivatives recorded in other liabilities, notional principal amount	20,700	18,000
Energy and weather contracts [Member]
Derivatives, Fair Value [Line Items]
Derivatives recorded in other assets, fair value	23,691	25,615
Derivatives recorded in other liabilities, fair value	22,184	35,366
Derivatives recorded in other assets, notional principal amount	76,702	81,624
Derivatives recorded in other liabilities, notional principal amount	$ 130,539	$ 135,050

Derivatives (Schedule Of Deri56

Derivatives (Schedule Of Derivative Gain) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	$ 91	$ 1,343	$ 510	$ 1,952
Total gains from derivatives	3,006	1,131	7,678	1,254
Foreign Exchange Forward [Member]
Derivative [Line Items]
Derivatives included in net foreign exchange losses from foreign exchange forward contracts	(343)	(172)	1,126	(399)
Interest Rate Future [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(27)	115	95	135
Credit Default Swap [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	9	14	9	14
Interest Rate Swap [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	320	(316)	(235)	(1,081)
Interest Rate Swaption [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	0	(1)	28	428
TBA [Member]
Derivative [Line Items]
Derivatives included in net realized and unrealized gains	(211)	1,531	613	2,456
Energy and weather contracts [Member]
Derivative [Line Items]
Derivatives included in other underwriting income (loss) from energy and weather contracts	$ 3,258	$ (40)	$ 6,042	$ (299)

Stock-Based Employee Compensa57

Stock-Based Employee Compensation And Other Stock Plans (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised		$ 300,000		$ 300,000
Proceeds from stock options exercised		$ 500,000		$ 500,000
Restricted shares and RSUs, grants in period	31,690	97,646	504,352	433,417
Restricted shares and RSUs weighted average grant date fair value	$ 2,000,000	$ 5,100,000	$ 30,000,000	$ 22,700,000
Aggregate fair value of restricted shares and RSUs vested	7,800,000	8,300,000	21,600,000	18,500,000
Expenses related to employee stock purchase plan	$ 79,000	$ 55,000	$ 144,000	$ 109,000
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	160,000	160,000	160,000	160,000
Number of options exercised	0	15,000	0	15,000
Compensation costs recognized in earnings	$ 500,000	$ 900,000	$ 1,000,000	$ 2,000,000
Compensation costs not yet recognized - stock options	1,600,000	3,700,000	1,600,000	3,700,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs recognized in earnings	7,600,000	6,600,000	16,900,000	15,800,000
Compensation costs not yet recognized - restricted stock	$ 34,000,000	$ 31,800,000	$ 34,000,000	$ 31,800,000
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	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
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	31,690	97,646	504,352	433,417
Settled			(445,083)
Forfeited			(3,301)
Unvested, end of period	1,346,862		1,346,862
Number of Shares/Units, Outstanding, end of period	1,346,862		1,290,894
Aggregate Intrinsic Value, Outstanding, end of period	$ 88,489

Segment Reporting (Summary Of T

Segment Reporting (Summary Of The Segment Revenues, Results And Reserve For Losses And Loss Expenses) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Gross premiums written		$ 861,184	$ 689,425	$ 2,162,616	$ 1,846,940
Ceded premiums written		(302,101)	(177,998)	(838,579)	(536,808)
Net premiums written		559,083	511,427	1,324,037	1,310,132
Net premiums earned		458,135	481,538	847,994	877,804
Other underwriting income (loss)		1,389	(4,824)	3,795	(6,062)
Total revenue		459,524	476,714	851,789	871,742
Net losses and loss expenses		239,122	259,196	411,058	436,092
Acquisition expenses		84,971	78,601	167,064	150,758
General and administrative expenses		54,965	58,312	109,855	117,813
Total expenses		379,058	396,109	687,977	704,663
Underwriting income		80,466	80,605	163,812	167,079
Net investment income		32,252	39,302	74,113	80,292
Corporate expenses		(12,634)	(28,143)	(24,902)	(41,848)
Net foreign exchange losses		(12,981)	(319)	(20,533)	(3,283)
Net realized and unrealized gains		9,680	3,411	27,869	8,283
Net impairment losses recognized in earnings		(424)	(198)	(1,073)	(309)
Amortization of intangibles		(1,579)	(1,623)	(3,178)	(3,240)
Interest expense		(9,062)	(9,732)	(18,121)	(18,783)
Income before income taxes		$ 85,718	$ 83,303	$ 197,987	$ 188,191
Net loss ratio		52.20%	53.80%	48.50%	49.60%
Acquisition expense ratio		18.50%	16.30%	19.70%	17.20%
General and administrative expense ratio	[1]	14.80%	18.00%	15.90%	18.20%
Combined ratio		85.50%	88.10%	84.10%	85.00%
Reserve for losses and loss expenses		$ 3,833,525	$ 3,963,393	$ 3,833,525	$ 3,963,393	$ 3,846,859
Insurance [Member]
Segment Reporting Information [Line Items]
Gross premiums written		468,866	321,526	1,205,084	973,802
Ceded premiums written		(278,567)	(142,488)	(710,746)	(451,737)
Net premiums written		190,299	179,038	494,338	522,065
Net premiums earned		201,460	218,563	337,324	362,584
Other underwriting income (loss)		0	0	0	0
Total revenue		201,460	218,563	337,324	362,584
Net losses and loss expenses		145,483	149,567	219,995	238,100
Acquisition expenses		17,702	15,128	33,585	27,389
General and administrative expenses		28,567	35,969	57,409	72,668
Total expenses		191,752	200,664	310,989	338,157
Underwriting income		$ 9,708	$ 17,899	$ 26,335	$ 24,427
Net loss ratio		72.20%	68.50%	65.20%	65.70%
Acquisition expense ratio		8.80%	6.90%	10.00%	7.60%
General and administrative expense ratio		14.20%	16.40%	17.00%	20.00%
Combined ratio		95.20%	91.80%	92.20%	93.30%
Reserve for losses and loss expenses		$ 2,157,769	$ 2,143,921	$ 2,157,769	$ 2,143,921
Reinsurance [Member]
Segment Reporting Information [Line Items]
Gross premiums written		392,318	367,899	957,532	873,138
Ceded premiums written		(23,534)	(35,510)	(127,833)	(85,071)
Net premiums written		368,784	332,389	829,699	788,067
Net premiums earned		256,675	262,975	510,670	515,220
Other underwriting income (loss)		1,389	(4,824)	3,795	(6,062)
Total revenue		258,064	258,151	514,465	509,158
Net losses and loss expenses		93,639	109,629	191,063	197,992
Acquisition expenses		67,269	63,473	133,479	123,369
General and administrative expenses		26,398	22,343	52,446	45,145
Total expenses		187,306	195,445	376,988	366,506
Underwriting income		$ 70,758	$ 62,706	$ 137,477	$ 142,652
Net loss ratio		36.50%	41.70%	37.40%	38.50%
Acquisition expense ratio		26.20%	24.10%	26.10%	23.90%
General and administrative expense ratio		10.30%	8.50%	10.30%	8.70%
Combined ratio		73.00%	74.30%	73.80%	71.10%
Reserve for losses and loss expenses		$ 1,675,756	$ 1,819,472	$ 1,675,756	$ 1,819,472
[1]	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		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenue from External Customer [Line Items]
Gross premiums written	$ 861,184	$ 689,425	$ 2,162,616	$ 1,846,940
Net premiums written	559,083	511,427	1,324,037	1,310,132
Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	468,866	321,526	1,205,084	973,802
Net premiums written	190,299	179,038	494,338	522,065
Agriculture Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	112,012	80,540	628,928	608,434
Net premiums written	22,677	45,826	225,137	327,471
Casualty And Other Specialty Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	146,056	108,030	246,738	175,683
Net premiums written	65,302	56,475	110,360	93,288
Professional Lines Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	96,736	74,650	151,496	113,430
Net premiums written	43,443	29,846	67,674	44,416
Property, Marine And Energy Insurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	114,062	58,306	177,922	76,255
Net premiums written	58,877	46,891	91,167	56,890
Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	392,318	367,899	957,532	873,138
Net premiums written	368,784	332,389	829,699	788,067
Catastrophe Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	139,833	158,372	264,240	285,020
Net premiums written	122,305	123,411	175,765	202,374
Property Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	30,560	42,887	156,260	209,300
Net premiums written	30,118	42,886	153,567	209,208
Casualty Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	48,132	30,875	106,230	115,857
Net premiums written	48,132	30,868	106,230	114,260
Professional Lines Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	134,241	84,117	178,098	109,736
Net premiums written	134,241	84,117	178,098	109,736
Specialty Reinsurance [Member]
Revenue from External Customer [Line Items]
Gross premiums written	39,552	51,648	252,704	153,225
Net premiums written	$ 33,988	$ 51,107	$ 216,039	$ 152,489

Commitments And Contingencies61

Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Reinsurance Recoverables	$ 942.8	$ 889.1
Collateral held related to ceded reinsurance agreements	221	199.7
Amount of letters of credit outstanding	192.4	209.9
Securities pledged as collateral obligation	151	130.6
Cash and investments pledged under letters of credit facility	$ 219.4	$ 240

Commitments And Contingencies62

Commitments And Contingencies (Schedule Of Percentage Of Net Premiums Written) (Details)	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Revenue from External Customer [Line Items]
Percentage of net premium written	53.30%	49.90%
Aon Benfield [Member]
Revenue from External Customer [Line Items]
Percentage of net premium written	16.20%	16.00%
Willis Companies [Member]
Revenue from External Customer [Line Items]
Percentage of net premium written	10.50%	11.80%
Marsh & Mclennan Companies, Inc. [Member]
Revenue from External Customer [Line Items]
Percentage of net premium written	26.60%	22.10%

Commitments And Contingencies63

Commitments And Contingencies (Deposits) (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
UNITED STATES [Member]
Statutory Accounting Practices [Line Items]
Assets Held by Insurance Regulators	$ 204	$ 205.2

Commitments And Contingencies64

Commitments And Contingencies (Schedule Of Future Minimum Lease Commitments) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 14,663
2,017	14,111
2,018	13,811
2,019	13,251
2,020	13,501
2021 and thereafter	28,570
Total	97,907
Total lease expenses under operating leases	$ 6,400	$ 8,200

Subsequent Event (Narrative) (D

Subsequent Event (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Jul. 31, 2015
Subsequent Event [Line Items]
Acquisition transaction costs	$ 3.5	$ 4.5
Subsequent Event [Member]
Subsequent Event [Line Items]
Investment banking fees			$ 15

Subsequent Event (Purchase Pric

Subsequent Event (Purchase Price) (Details) - USD ($) $ / shares in Units, $ in Thousands		Jul. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Subsequent Event [Line Items]
Number of Montpelier common shares outstanding immediately prior to the closing of the Merger			45,156,845	44,765,153
Subsequent Event [Member]
Subsequent Event [Line Items]
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
Total consideration		1,470,846
Total consideration received by Montpelier common shareholders		1,921,947
Net purchase price		$ 1,470,846
Subsequent Event [Member] | Montpelier [Member]
Subsequent Event [Line Items]
Number of Montpelier common shares outstanding immediately prior to the closing of the Merger		43,827,753
Fair value of restricted share units attributable to service period prior to merger date(1)	[1]	$ 33,327
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
[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 Endurance ordinary shares for each outstanding Montpelier restricted share unit rounded down to the next whole number of Endurance ordinary shares. The fair value of the Montpelier restricted share units was determined based on the closing price of Endurance 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.