Everest Re (EG) 10-Q 5 Aug 21 2021 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Aug. 01, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Fiscal Year Focus	2021
Document Transition Report	false
Entity File Number	1-15731
Entity Registrant Name	EVEREST RE GROUP, LTD.
Entity Incorporation State Country Code	D0
Entity Tax Identification Number	98-0365432
Entity Address Address Line 1	Seon Place – 4th Floor
Entity Address Address Line 2	141 Front Street
Entity Address Address Line 3	PO Box HM 845
Entity Address City Or Town	Hamilton
Entity Address Postal Zip Code	HM 19
Entity Address Country	BM
City Area Code	441
Local Phone Number	295-0006
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Security 12b Title	Common Shares, $0.01 par value
Trading Symbol	RE
Security Exchange Name	NYSE
Entity Common Stock Shares Outstanding		39,872,807
Amendment Flag	false
Entity Central Index Key	0001095073
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
ASSETS:
Fixed maturities - available for sale, at market value (amortized cost: 2021, $20,718,717; 2020, $19,225,067, credit allowances: 2021, $(24,650); 2020, $(1,745))	$ 21,275,199	$ 20,040,173
Equity securities, at fair value	1,485,833	1,472,236
Short-term investments (cost: 2021, $629,943 ; 2020, $1,135,088)	629,943	1,134,950
Other invested assets (cost: 2021, $2,558,631 ; 2020, $2,012,581)	2,558,631	2,012,581
Cash	1,106,345	801,651
Total investments and cash	27,055,951	25,461,591
Accrued investment income	170,907	141,304
Premiums receivable	3,199,024	2,680,562
Reinsurance receivables	2,032,363	1,994,555
Funds held by reinsureds	798,780	716,655
Deferred acquisition costs	748,897	622,053
Prepaid reinsurance premiums	495,657	412,015
Income taxes net recoverable		17,253
Other assets	868,477	742,369
TOTAL ASSETS	35,370,056	32,788,357
LIABILITIES:
Reserve for losses and loss adjustment expenses	17,645,762	16,398,997
Future policy benefit reserve	36,497	37,723
Unearned premium reserve	4,024,050	3,501,359
Funds held under reinsurance treaties	17,520	15,807
Other net payable to reinsurers	379,524	294,347
Losses in course of payment	198,352	127,971
Long term notes due 5/1/2067	223,724	223,674
Borrowings from FHLB	310,000	310,000
Accrued interest on debt and borrowings	9,641	10,460
Unsettled securities payable	124,559	206,693
Income taxes net payable	35,089
Other liabilities	571,511	558,432
Total liabilities	24,953,267	23,062,181
Commitments and contingencies (Note 7)
SHAREHOLDERS' EQUITY:
Preferred shares, par value: $0.01; 50,000 shares authorized; no shares issued and outstanding
Common shares, par value: $0.01; 200,000 shares authorized; (2021) 69,817 and (2020) 69,620 outstanding before treasury shares	698	696
Additional paid-in capital	2,256,390	2,245,301
Accumulated other comprehensive income (loss), net of deferred income tax expense (benefit) of $56,797 at 2021 and $80,451 at 2020	357,178	534,899
Treasury shares, at cost; 29,802 shares (2021) and 29,636 shares (2020)	(3,662,499)	(3,622,172)
Retained earnings	11,465,022	10,567,452
Total shareholders' equity	10,416,789	9,726,176
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	35,370,056	32,788,357
Senior Notes [Member] | 4.868% Senior Notes due 6/1/2044 [Member]
LIABILITIES:
Senior notes	397,254	397,194
Senior Notes [Member] | 3.5% Senior notes due 10/15/2050 [Member]
LIABILITIES:
Senior notes	$ 979,784	$ 979,524

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Fixed maturities - available for sale, at market value, amortized cost	$ 20,718,717	$ 19,225,067
Fixed maturities - available for sale, at market value, allowance for credit loss	(24,650)	(1,745)
Short-term investments, at cost	629,943	1,135,088
Other invested assets, at cost	$ 2,558,631	$ 2,012,581
Preferred shares, par value	$ 0.01	$ 0.01
Preferred shares, authorized	50,000,000	50,000,000
Preferred shares, issued	0	0
Preferred shares, outstanding	0	0
Common shares, par value	$ 0.01	$ 0.01
Common Stock, Shares Authorized	200,000,000	200,000,000
Common shares, outstanding	69,817,000	69,620,000
Accumulated other comprehensive income (loss), net deferred income tax expense (benefit)	$ 56,797	$ 80,451
Treasury shares	29,802,000	29,636,000
Senior Notes [Member] | 4.868% Senior Notes due 6/1/2044 [Member]
Debt instrument, maturity date	Jun. 1, 2044	Jun. 1, 2044
Senior Notes [Member] | 3.5% Senior notes due 10/15/2050 [Member]
Debt instrument, maturity date	Oct. 15, 2050	Oct. 15, 2050
Subordinated Debt [Member] | 6.6 % Long Term Subordinated Notes [Member]
Debt instrument, maturity date	May 1, 2067	May 1, 2067

Consolidated Statements Of Oper

Consolidated Statements Of Operations And Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
REVENUES:
Premiums earned	$ 2,558,372	$ 2,042,405	$ 4,946,237	$ 4,079,219
Net investment income	407,095	38,083	667,508	185,883
Net realized capital gains (losses):
Credit allowances on fixed maturity securities	(15,927)	(4,063)	(22,904)	(25,837)
Other net realized capital gains (losses)	120,036	188,711	165,915	(103)
Total net realized capital gains (losses)	104,109	184,648	143,011	(25,940)
Other income (expense)	7,114	(20,621)	63,707	(12,631)
Total revenues	3,076,690	2,244,515	5,820,463	4,226,531
CLAIMS AND EXPENSES:
Incurred losses and loss adjustment expenses	1,586,141	1,407,016	3,297,560	2,837,856
Commission, brokerage, taxes and fees	557,749	466,316	1,046,760	914,838
Other underwriting expenses	140,844	118,130	283,075	246,990
Corporate expenses	16,168	8,733	28,546	18,566
Interest, fees and bond issue cost amortization expense	15,607	7,253	31,246	14,836
Total claims and expenses	2,316,509	2,007,448	4,687,187	4,033,086
INCOME (LOSS) BEFORE TAXES	760,181	237,067	1,133,276	193,445
Income tax expense (benefit)	80,199	46,187	111,432	(14,047)
NET INCOME (LOSS)	679,982	190,880	1,021,844	207,492
Other comprehensive income (loss), net of tax:
Unrealized appreciation (depreciation) ("URA(D)") on securities arising during the period	84,171	551,753	(204,444)	272,354
Reclassification adjustment for realized losses (gains) included in net income (loss)	1,590	(7,257)	(2,076)	24,142
Total URA(D) on securities arising during the period	85,761	544,496	(206,520)	296,496
Foreign currency translation adjustments	34,295	20,586	24,713	(30,238)
Reclassification adjustment for amortization of net (gain) loss included in net income (loss)	2,043	1,806	4,086	2,726
Total benefit plan net gain (loss) for the period	2,043	1,806	4,086	2,726
Total other comprehensive income (loss), net of tax	122,099	566,888	(177,721)	268,984
COMPREHENSIVE INCOME (LOSS)	$ 802,081	$ 757,768	$ 844,123	$ 476,476
EARNINGS PER COMMON SHARE:
Basic	$ 16.97	$ 4.78	$ 25.50	$ 5.14
Diluted	$ 16.95	$ 4.77	$ 25.47	$ 5.13

Consolidated Statements Of Chan

Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock Outstanding [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss), Net of Deferred Income Taxes [Member]	Retained Earnings [Member]	Retained Earnings [Member]Cumulative Effect Period Of Adoption Adjustment [Member]	Treasury Stock [Member]
Balance at Dec. 31, 2019			$ 694	$ 2,219,660	$ 28,152	$ 10,306,571		$ (3,422,152)
Balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2019							$ (4,214)
Balance, shares at Dec. 31, 2019		40,798,963
Issued during the period, net, shares		159,423
Treasury shares acquired, shares		(970,892)
Issued during the period, net			2
Share-based compensation plans				(3,181)
Net increase (decrease) during the period					(297,903)
Net income (loss)						16,612
Dividends declared ($1.55 per share 2021 and $1.55 per share 2020)						(63,277)
Purchase of treasury shares								(200,020)
Balance at Mar. 31, 2020			696	2,216,479	(269,751)	10,255,692		(3,622,172)
Balance, shares at Mar. 31, 2020		39,987,494
Balance at Dec. 31, 2019			694	2,219,660	28,152	10,306,571		(3,422,152)
Balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2019							(4,214)
Balance, shares at Dec. 31, 2019		40,798,963
Net increase (decrease) during the period	$ 268,984
Net income (loss)	207,492
Dividends declared ($1.55 per share 2021 and $1.55 per share 2020)	(125,205)
Balance at Jun. 30, 2020	9,286,299		696	2,225,993	297,137	10,384,645		(3,622,172)
Balance, shares at Jun. 30, 2020		39,971,645
Balance at Mar. 31, 2020			696	2,216,479	(269,751)	10,255,692		(3,622,172)
Balance, shares at Mar. 31, 2020		39,987,494
Issued during the period, net, shares		(15,849)
Treasury shares acquired, shares		0
Issued during the period, net
Share-based compensation plans				9,514
Net increase (decrease) during the period	566,888				566,888
Net income (loss)	190,880					190,880
Dividends declared ($1.55 per share 2021 and $1.55 per share 2020)	(61,927)					(61,927)
Purchase of treasury shares
Balance at Jun. 30, 2020	9,286,299		696	2,225,993	297,137	10,384,645		(3,622,172)
Balance, shares at Jun. 30, 2020		39,971,645
Balance at Dec. 31, 2020	$ 9,726,176		696	2,245,301	534,899	10,567,452		(3,622,172)
Balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2020
Balance, shares at Dec. 31, 2020	69,620,000	39,983,481
Issued during the period, net, shares		196,481
Treasury shares acquired, shares		(97,462)
Issued during the period, net			2
Share-based compensation plans				436
Net increase (decrease) during the period					(299,820)
Net income (loss)						341,862
Dividends declared ($1.55 per share 2021 and $1.55 per share 2020)						(62,228)
Purchase of treasury shares								(23,545)
Balance at Mar. 31, 2021			698	2,245,737	235,079	10,847,086		(3,645,717)
Balance, shares at Mar. 31, 2021		40,082,500
Balance at Dec. 31, 2020	$ 9,726,176		696	2,245,301	534,899	10,567,452		(3,622,172)
Balance (Accounting Standards Update 2016-13 [Member]) at Dec. 31, 2020
Balance, shares at Dec. 31, 2020	69,620,000	39,983,481
Net increase (decrease) during the period	$ (177,721)
Net income (loss)	1,021,844
Dividends declared ($1.55 per share 2021 and $1.55 per share 2020)	(124,274)
Balance at Jun. 30, 2021	$ 10,416,789		698	2,256,390	357,178	11,465,022		(3,662,499)
Balance, shares at Jun. 30, 2021	69,817,000	40,015,340
Balance at Mar. 31, 2021			698	2,245,737	235,079	10,847,086		(3,645,717)
Balance, shares at Mar. 31, 2021		40,082,500
Issued during the period, net, shares		940
Treasury shares acquired, shares		(68,100)
Issued during the period, net
Share-based compensation plans				10,653
Net increase (decrease) during the period	$ 122,099				122,099
Net income (loss)	679,982					679,982
Dividends declared ($1.55 per share 2021 and $1.55 per share 2020)	(62,045)					(62,046)
Purchase of treasury shares								(16,782)
Balance at Jun. 30, 2021	$ 10,416,789		$ 698	$ 2,256,390	$ 357,178	$ 11,465,022		$ (3,662,499)
Balance, shares at Jun. 30, 2021	69,817,000	40,015,340

Consolidated Statements Of Ch_2

Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020
Consolidated Statements Of Changes In Shareholders' Equity [Abstract]
Dividends declared	$ 1.55	$ 1.55	$ 1.55	$ 1.55

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 1,021,844	$ 207,492
Adjustments to reconcile net income to net cash provided by operating activities:
Decrease (increase) in premiums receivable	(499,647)	(252,609)
Decrease (increase) in funds held by reinsureds, net	(79,485)	(23,498)
Decrease (increase) in reinsurance receivables	15,836	(147,515)
Decrease (increase) in income taxes	76,452	(25,000)
Decrease (increase) in prepaid reinsurance premiums	(71,566)	(29,699)
Increase (decrease) in reserve for losses and loss adjustment expenses	1,144,620	800,816
Increase (decrease) in future policy benefit reserve	(1,226)	(1,933)
Increase (decrease) in unearned premiums	500,077	159,744
Increase (decrease) in other net payable to reinsurers	72,850	89,499
Increase (decrease) in losses in course of payment	70,653	147,427
Change in equity adjustments in limited partnerships	(377,120)	84,066
Distribution of limited partnership income	49,053	40,447
Change in other assets and liabilities, net	(211,735)	(10,313)
Non-cash compensation expense	22,439	19,175
Amortization of bond premium (accrual of bond discount)	37,928	20,547
Net realized capital (gains) losses	(143,011)	25,940
Net cash provided by (used in) operating activities	1,627,962	1,104,586
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from fixed maturities matured/called - available for sale, at market value	1,897,536	1,261,650
Proceeds from fixed maturities sold - available for sale, at market value	599,737	990,273
Proceeds from equity securities sold, at fair value	474,663	213,185
Distributions from other invested assets	112,398	164,975
Cost of fixed maturities acquired - available for sale, at market value	(3,949,973)	(2,301,701)
Cost of equity securities acquired, at fair value	(360,016)	(224,086)
Cost of other invested assets acquired	(309,691)	(343,332)
Net change in short-term investments	506,285	(439,457)
Net change in unsettled securities transactions	(103,527)	49,504
Net cash provided by (used in) investing activities	(1,132,588)	(628,989)
CASH FLOWS FROM FINANCING ACTIVITIES:
Common shares issued during the period for share-based compensation, net of expense	(11,349)	(12,841)
Purchase of treasury shares	(40,328)	(200,019)
Dividends paid to shareholders	(124,274)	(125,205)
Cost of debt repurchase		(10,647)
Cost of shares withheld on settlements of share-based compensation awards	(13,713)	(14,141)
Net cash provided by (used in) financing activities	(189,664)	(362,853)
EFFECT OF EXCHANGE RATE CHANGES ON CASH	(1,016)	1,699
Net increase (decrease) in cash	304,694	114,443
Cash, beginning of period	801,651	808,036
Cash, end of period	1,106,345	922,479
SUPPLEMENTAL CASH FLOW INFORMATION:
Income taxes paid (recovered)	34,780	10,895
Interest paid	$ 31,695	$ 14,992

General

General	6 Months Ended
	Jun. 30, 2021
General [Abstract]
General	1. GENERAL Everest Re Group, Ltd. (“Group”), a Bermuda company, through its subsidiaries, principally provides reinsurance and insurance in the U.S., Bermuda and international markets. As used in this document, “Company” means Group and its subsidiaries.

Basis Of Presentation

Basis Of Presentation	6 Months Ended
	Jun. 30, 2021
Basis Of Presentation [Abstract]
Basis Of Presentation	2. BASIS OF PRESENTATION The unaudited consolidated financial statements of the Company as of June 30, 2021 and December 31, 2020 and for the three and six months ended June 30, 2021 and 2020 include all adjustments, consisting of normal recurring accruals, which, in the opinion of management, are necessary for a fair statement of the results on an interim basis. Certain financial information, which is normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”), has been omitted since it is not required for interim reporting purposes. The December 31, 2020 consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by GAAP. The results for the three and six months ended June 30, 2021 and 2020 are not necessarily indicative of the results for a full year. These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the years ended December 31, 2020, 2019 and 2018, included in the Company’s most recent Form 10-K filing. The Company consolidates the results of operations and financial position of all voting interest entities ("VOE") in which the Company has a controlling financial interest and all variable interest entities ("VIE") in which the Company is considered to be the primary beneficiary. The consolidation assessment, including the determination as to whether an entity qualifies as a VIE or VOE, depends on the facts and circumstances surrounding each entity. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities (and disclosure of contingent assets and liabilities) at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Ultimate actual results could differ, possibly materially, from those estimates. This is particularly true given the fluid and continuing nature of the COVID-19 Pandemic. This is an ongoing event and so is the Company’s evaluation and analysis. While the Company’s analysis considers all aspects of its operations, it does not take into account legal, regulatory or legislative intervention that could retroactively mandate or expand coverage provisions. Given the uncertainties in the current public health and economic environment, there could be an adverse impact on results for the Property & Casualty industry and the Company for the remainder of the year. The impact is dependent on the shape and length of the economic recovery. All intercompany accounts and transactions have been eliminated. Certain reclassifications and format changes have been made to prior years’ amounts to conform to the 2021 presentation. Application of Recently Issued Accounting Standard Changes. Accounting for Income Taxes. In December 2019, The Financial Accounting Standards Board (“FASB”) issued ASU 2019-12, which provides simplification of existing guidance for income taxes, including the removal of certain exceptions related to recognition of deferred tax liabilities on foreign subsidiaries. The guidance is effective for annual reporting periods beginning after December 15, 2020 and interim periods within that annual reporting period. The Company adopted the guidance as of January 1, 2021. The adoption of ASU 2019-12 did not have a material impact on the Company’s financial statements. Accounting for Long Duration Contracts. In August 2018, FASB issued ASU 2018-12, which discusses changes to the recognition, measurement and presentation of long duration contracts. The main provisions of this guidance address the following: 1) In determining liability for future policy benefits, companies must review cash flow assumptions at least annually and the discount rate assumption at each reporting period date 2) Amortization of deferred acquisition costs has been simplified to be in constant level proportion to either premiums, gross profits or gross margins 3) Disaggregated roll forwards of beginning and ending liabilities for future policy benefits are required. The guidance was originally effective for annual reporting periods beginning after December 15, 2020 and interim periods within that annual reporting period. However, FASB issued ASU 2019-09 in November 2019 and then ASU 2020-11 in November 2021, which ultimately defers the effective date of ASU 2018-12 until annual reporting periods beginning after December 15, 2022. The Company is currently evaluating the impact of the adoption of ASU 2018-12 on its financial statements. Any issued guidance and pronouncements, other than those directly referenced above, are deemed by the Company to be either not applicable or immaterial to its financial statements.

Investments

Investments	6 Months Ended
	Jun. 30, 2021
Investments [Abstract]
Investments	3. INVESTMENTS The following tables show amortized cost, allowance for credit losses, gross unrealized appreciation, gross unrealized depreciation and market value of available for sale, fixed maturity securities as of the dates indicated: At June 30, 2021 Amortized Allowance for Unrealized Unrealized Market (Dollars in thousands) Cost Credit Losses Appreciation Depreciation Value Fixed maturity securities U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,259,149 $ - $ 29,365 $ ( 12,756) $ 1,275,758 Obligations of U.S. states and political subdivisions 574,398 - 35,933 ( 986) 609,345 Corporate securities 7,155,688 ( 18,475) 285,509 ( 63,018) 7,359,704 Asset-backed securities 3,141,971 ( 4,915) 35,316 ( 2,955) 3,169,417 Mortgage-backed securities Commercial 1,026,809 - 55,125 ( 3,535) 1,078,399 Agency residential 2,255,348 - 47,124 ( 12,205) 2,290,267 Non-agency residential 8,220 - 6 ( 15) 8,211 Foreign government securities 1,494,989 - 80,268 ( 21,296) 1,553,961 Foreign corporate securities 3,802,145 ( 1,260) 167,015 ( 37,763) 3,930,137 Total fixed maturity securities $ 20,718,717 $ ( 24,650) $ 735,661 $ ( 154,529) $ 21,275,199 At December 31, 2020 Amortized Allowance for Unrealized Unrealized Market (Dollars in thousands) Cost Credit Losses Appreciation Depreciation Value Fixed maturity securities U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,325,156 $ - $ 49,084 $ ( 7,134) $ 1,367,106 Obligations of U.S. states and political subdivisions 543,895 - 34,654 ( 1,254) 577,295 Corporate securities 6,824,800 ( 1,220) 380,677 ( 55,231) 7,149,026 Asset-backed securities 2,540,809 - 30,691 ( 5,698) 2,565,802 Mortgage-backed securities Commercial 915,923 - 75,275 ( 895) 990,303 Agency residential 2,206,139 - 64,663 ( 3,063) 2,267,739 Non-agency residential 5,187 - 9 ( 2) 5,194 Foreign government securities 1,565,260 ( 22) 102,587 ( 22,450) 1,645,375 Foreign corporate securities 3,297,898 ( 503) 204,023 ( 29,085) 3,472,333 Total fixed maturity securities $ 19,225,067 $ ( 1,745) $ 941,663 $ ( 124,812) $ 20,040,173 The amortized cost and market value of fixed maturity securities are shown in the following table by contractual maturity. Mortgage-backed securities are generally more likely to be prepaid than other fixed maturity securities. As the stated maturity of such securities may not be indicative of actual maturities, the totals for mortgage-backed and asset-backed securities are shown separately. At June 30, 2021 At December 31, 2020 Amortized Market Amortized Market (Dollars in thousands) Cost Value Cost Value Fixed maturity securities – available for sale: Due in one year or less $ 1,628,113 $ 1,638,768 $ 1,365,793 $ 1,374,674 Due after one year through five years 6,432,847 6,618,429 6,529,189 6,774,785 Due after five years through ten years 4,890,259 5,091,435 4,414,211 4,751,903 Due after ten years 1,335,150 1,380,273 1,247,816 1,309,773 Asset-backed securities 3,141,971 3,169,417 2,540,809 2,565,802 Mortgage-backed securities: Commercial 1,026,809 1,078,399 915,923 990,303 Agency residential 2,255,348 2,290,267 2,206,139 2,267,739 Non-agency residential 8,220 8,211 5,187 5,194 Total fixed maturity securities $ 20,718,717 $ 21,275,199 $ 19,225,067 $ 20,040,173 The changes in net unrealized appreciation (depreciation) for the Company’s investments are derived from the following sources for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Increase (decrease) during the period between the market value and cost of investments carried at market value, and deferred taxes thereon: Fixed maturity securities $ 97,127 $ 614,077 $ ( 235,581) $ 337,053 Change in unrealized appreciation (depreciation), pre-tax 97,127 614,077 ( 235,581) 337,053 Deferred tax benefit (expense) ( 11,366) ( 69,581) 29,061 ( 40,557) Change in unrealized appreciation (depreciation), net of deferred taxes, included in shareholders’ equity $ 85,761 $ 544,496 $ ( 206,520) $ 296,496 The Company reviews all of its fixed maturity, available for sale securities whose fair value has fallen below their amortized cost at the time of review. The Company then assesses whether the decline in value is due to non-credit related or credit related factors. In making its assessment, the Company evaluates the current market and interest rate environment as well as specific issuer information. Generally, a change in a security’s value caused by a change in the market, interest rate or foreign exchange environment does not constitute a credit impairment, but rather a non-credit related decline in market value. Non-credit related declines in market value are recorded as unrealized losses in accumulated other comprehensive income (loss). If the Company intends to sell the security or is more likely than not to sell the security, the Company records the entire fair value adjustment in net realized capital gains (losses) in the Company’s consolidated statements of operations and comprehensive income (loss). If the Company determines that the decline is credit related and the Company does not have the intent to sell the security; and it is more likely than not that the Company will not have to sell the security before recovery of its cost basis, the Company establishes a credit allowance equal to the estimated credit loss and is recorded in net realized capital gains (losses) in the Company’s consolidated statements of operations and comprehensive income (loss). The amount of the allowance for a given security will generally be the difference between a discounted cash flow model and the Company’s carrying value. The fair value adjustment that is non-credit related is recorded as a component of other comprehensive income (loss), net of tax, and is included in accumulated other comprehensive income (loss) in the Company’s consolidated balance sheets. The Company will adjust the credit allowance account for future changes in credit loss estimates for a security and record this adjustment through net realized capital gains (losses) in the Company’s consolidated statements of operations and comprehensive income (loss). The Company does not create an allowance for uncollectible interest. If interest is not received when due, the interest receivable is immediately reversed and no additional interest is accrued. If future interest is received that has not been accrued, it is recorded as income at that time. The Company’s assessments are based on the issuers’ current and expected future financial position, timeliness with respect to interest and/or principal payments, speed of repayments and any applicable credit enhancements or breakeven constant default rates on mortgage-backed and asset-backed securities, as well as relevant information provided by rating agencies, investment advisors and analysts. Retrospective adjustments are employed to recalculate the values of asset-backed securities. All of the Company’s asset-backed and mortgage-backed securities have a pass-through structure. Each acquisition lot is reviewed to recalculate the effective yield. The recalculated effective yield is used to derive a book value as if the new yield were applied at the time of acquisition. Outstanding principal factors from the time of acquisition to the adjustment date are used to calculate the prepayment history for all applicable securities. Conditional prepayment rates, computed with life to date factor histories and weighted average maturities, are used in the calculation of projected prepayments for pass-through security types. The tables below display the aggregate market value and gross unrealized depreciation of fixed maturity securities, by security type and contractual maturity, in each case subdivided according to length of time that individual securities had been in a continuous unrealized loss position for the periods indicated: Duration of Unrealized Loss at June 30, 2021 By Security Type Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities - available for sale U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 341,846 $ ( 12,494) $ 2,620 $ ( 262) $ 344,466 $ ( 12,756) Obligations of U.S. states and political subdivisions 23,662 ( 986) - - 23,662 ( 986) Corporate securities 1,598,159 ( 61,141) 37,936 ( 1,877) 1,636,095 ( 63,018) Asset-backed securities 710,904 ( 2,955) - - 710,904 ( 2,955) Mortgage-backed securities Commercial 134,941 ( 3,535) - - 134,941 ( 3,535) Agency residential 1,020,232 ( 11,327) 43,983 ( 878) 1,064,215 ( 12,205) Non-agency residential 1,309 ( 15) - - 1,309 ( 15) Foreign government securities 304,722 ( 20,686) 3,107 ( 610) 307,829 ( 21,296) Foreign corporate securities 861,693 ( 34,534) 30,035 ( 3,229) 891,728 ( 37,763) Total fixed maturity securities $ 4,997,468 $ ( 147,673) $ 117,681 $ ( 6,856) $ 5,115,149 $ ( 154,529) Duration of Unrealized Loss at June 30, 2021 By Maturity Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities Due in one year or less $ 260,687 $ ( 15,951) $ 5,846 $ ( 471) $ 266,533 $ ( 16,422) Due in one year through five years 1,385,520 ( 51,928) 48,824 ( 3,048) 1,434,344 ( 54,976) Due in five years through ten years 1,153,553 ( 48,557) 19,028 ( 2,459) 1,172,581 ( 51,016) Due after ten years 330,322 ( 13,405) - - 330,322 ( 13,405) Asset-backed securities 710,904 ( 2,955) - - 710,904 ( 2,955) Mortgage-backed securities 1,156,482 ( 14,877) 43,983 ( 878) 1,200,465 ( 15,755) Total fixed maturity securities $ 4,997,468 $ ( 147,673) $ 117,681 $ ( 6,856) $ 5,115,149 $ ( 154,529) The aggregate market value and gross unrealized losses related to investments in an unrealized loss position at June 30, 2021 were $ 5,115,149 thousand and $ 154,529 thousand, respectively. The market value of securities for the single issuer (the United States government) whose securities comprised the largest unrealized loss position at June 30, 2021, did not exceed 1.6% of the overall market value of the Company’s fixed maturity securities. The market value of the securities for the issuer with the second largest unrealized loss position at June 30, 2021, comprised less than 0.3% of the Company’s fixed maturity securities. In addition, as indicated on the above table, there was no significant concentration of unrealized losses in any one market sector. The $ 147,673 thousand of unrealized losses related to fixed maturity securities that have been in an unrealized loss position for less than one year were generally comprised of domestic and foreign corporate securities, U.S. Treasury and government securities, foreign government securities and agency residential mortgage-backed securities. Of these unrealized losses, $ 133,996 thousand were related to securities that were rated investment grade by at least one nationally recognized statistical rating agency. The $ 6,856 thousand of unrealized losses related to fixed maturity securities in an unrealized loss position for more than one year related primarily to foreign and domestic corporate securities. Of these unrealized losses, $ 6,678 thousand were related to securities that were rated investment grade by at least one nationally recognized statistical rating agency. There was no gross unrealized depreciation for mortgage-backed securities related to sub-prime and alt-A loans. In all instances, there were no projected cash flow shortfalls to recover the full book value of the investments and the related interest obligations. The mortgage-backed securities still have excess credit coverage and are current on interest and principal payments. The Company, given the size of its investment portfolio and capital position, does not have the intent to sell these securities; and it is more likely than not that the Company will not have to sell the security before recovery of its cost basis. In addition, all securities currently in an unrealized loss position are current with respect to principal and interest payments. The tables below display the aggregate market value and gross unrealized depreciation of fixed maturity securities, by security type and contractual maturity, in each case subdivided according to length of time that individual securities had been in a continuous unrealized loss position for the periods indicated: Duration of Unrealized Loss at December 31, 2020 By Security Type Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities - available for sale U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 135,190 $ ( 7,134) $ - $ - $ 135,190 $ ( 7,134) Obligations of U.S. states and political subdivisions 19,524 ( 999) 4,059 ( 255) 23,583 ( 1,254) Corporate securities 669,755 ( 26,159) 247,962 ( 29,072) 917,717 ( 55,231) Asset-backed securities 235,566 ( 4,768) 85,595 ( 930) 321,161 ( 5,698) Mortgage-backed securities Commercial 53,511 ( 578) 6,592 ( 317) 60,103 ( 895) Agency residential 434,447 ( 2,016) 50,353 ( 1,047) 484,800 ( 3,063) Non-agency residential 185 ( 2) - - 185 ( 2) Foreign government securities 114,755 ( 8,813) 150,812 ( 13,637) 265,567 ( 22,450) Foreign corporate securities 354,548 ( 17,489) 115,595 ( 11,596) 470,143 ( 29,085) Total fixed maturity securities $ 2,017,481 $ ( 67,958) $ 660,968 $ ( 56,854) $ 2,678,449 $ ( 124,812) Duration of Unrealized Loss at December 31, 2020 By Maturity Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities Due in one year or less $ 96,144 $ ( 4,942) $ 112,419 $ ( 12,071) $ 208,563 $ ( 17,013) Due in one year through five years 653,816 ( 32,469) 283,866 ( 21,319) 937,682 ( 53,788) Due in five years through ten years 422,517 ( 19,392) 49,749 ( 2,034) 472,266 ( 21,426) Due after ten years 121,295 ( 3,791) 72,394 ( 19,136) 193,689 ( 22,927) Asset-backed securities 235,566 ( 4,768) 85,595 ( 930) 321,161 ( 5,698) Mortgage-backed securities 488,143 ( 2,596) 56,945 ( 1,364) 545,088 ( 3,960) Total fixed maturity securities $ 2,017,481 $ ( 67,958) $ 660,968 $ ( 56,854) $ 2,678,449 $ ( 124,812) The aggregate market value and gross unrealized losses related to investments in an unrealized loss position at December 31, 2020 were $ 2,678,449 thousand and $ 124,812 thousand, respectively. The market value of securities for the single issuer whose securities comprised the largest unrealized loss position at December 31, 2020, did not exceed 0.7.% of the overall market value of the Company’s fixed maturity securities. The market value of the securities for the issuer with the second largest unrealized loss comprised less than 0.1% of the Company’s fixed maturity securities. In addition, as indicated on the above table, there was no significant concentration of unrealized losses in any one market sector. The $ 67,958 thousand of unrealized losses related to fixed maturity securities that have been in an unrealized loss position for less than one year were generally comprised of domestic and foreign corporate securities and foreign government securities. Of these unrealized losses, $ 63,424 thousand were related to securities that were rated investment grade by at least one nationally recognized statistical rating agency. The $ 56,854 thousand of unrealized losses related to fixed maturity securities in an unrealized loss position for more than one year related primarily to domestic and foreign corporate securities, foreign government securities and agency residential mortgage-backed securities. Of these unrealized losses, $ 33,533 thousand were related to securities that were rated investment grade by at least one nationally recognized statistical rating agency. There was no gross unrealized depreciation for mortgage-backed securities related to sub-prime and alt-A loans. In all instances, there were no projected cash flow shortfalls to recover the full book value of the investments and the related interest obligations. The mortgage-backed securities still have excess credit coverage and are current on interest and principal payments. The components of net investment income are presented in the table below for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Fixed maturities $ 148,262 $ 133,918 $ 289,178 $ 271,842 Equity securities 3,493 3,662 8,331 7,183 Short-term investments and cash 773 1,687 953 3,862 Other invested assets: Limited partnerships 239,966 ( 88,254) 354,299 ( 66,686) Other 25,855 ( 2,962) 31,874 ( 16,033) Gross investment income before adjustments 418,349 48,051 684,635 200,168 Funds held interest income (expense) 3,287 2,021 11,253 10,237 Future policy benefit reserve income (expense) ( 170) ( 303) ( 461) ( 514) Gross investment income 421,466 49,769 695,427 209,891 Investment expenses ( 14,371) ( 11,686) ( 27,919) ( 24,008) Net investment income $ 407,095 $ 38,083 $ 667,508 $ 185,883 The Company records results from limited partnership investments on the equity method of accounting with changes in value reported through net investment income. The net investment income from limited partnerships is dependent upon the Company’s share of the net asset values of interests underlying each limited partnership. Due to the timing of receiving financial information from these partnerships, the results are generally reported on a one month or quarter lag. If the Company determines there has been a significant decline in value of a limited partnership during this lag period, a loss will be recorded in the period in which the Company identifies the decline. The Company had contractual commitments to invest up to an additional $ 2,866,741 thousand in limited partnerships and private placement loan securities at June 30, 2021. These commitments will be funded when called in accordance with the partnership and loan agreements, which have investment periods that expire, unless extended, through 2026 The Company participates in a private placement liquidity sweep facility (“the facility”). The primary purpose of the facility is to enhance the Company’s return on its short-term investments and cash positions. The facility invests in high quality, short-duration securities and permits daily liquidity. The Company consolidates its participation in the facility. As of June 30, 2021, the market value of investments in the facility consolidated within the Company’s balance sheets was $ 575,807 thousand. The components of net realized capital gains (losses) are presented in the tables below for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Fixed maturity securities, market value: Allowance for credit losses $ ( 15,927) $ ( 4,063) $ ( 22,904) $ ( 25,837) Gains (losses) from sales 10,060 9,619 19,234 ( 4,457) Fixed maturity securities, fair value: Gains (losses) from sales - - - - Gains (losses) from fair value adjustments - ( 272) - ( 1,395) Equity securities, fair value: Gains (losses) from sales 3,755 16,274 9,993 ( 11,325) Gains (losses) from fair value adjustments 103,525 161,694 132,581 17,691 Other invested assets 2,748 1,293 4,094 ( 1,034) Short-term investments gain (loss) ( 52) 103 13 417 Total net realized capital gains (losses) $ 104,109 $ 184,648 $ 143,011 $ ( 25,940) Roll Forward of Allowance for Credit Losses Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 Foreign Foreign Foreign Foreign Corporate Asset-Backed Government Corporate Corporate Asset-Backed Government Corporate Securities Securities Securities Securities Total Securities Securities Securities Securities Total (Dollars in thousands) Beginning Balance $ ( 3,603) $ ( 4,915) $ - $ ( 205) $ ( 8,723) $ ( 1,220) $ - $ ( 22) $ ( 503) $ ( 1,745) Credit losses on securities where credit losses were not previously recorded ( 13,537) - - ( 1,055) ( 14,592) ( 15,920) ( 4,915) - ( 1,055) ( 21,890) Increases in allowance on previously - impaired securities ( 1,468) - - - ( 1,468) ( 1,468) - - - ( 1,468) Decreases in allowance on previously - impaired securities - - - - - - - - - - Reduction in allowance due to disposals 133 - - - 133 133 - 22 298 453 Balance as of June 30, 2021 $ ( 18,475) $ ( 4,915) $ - $ ( 1,260) $ ( 24,650) $ ( 18,475) $ ( 4,915) $ - $ ( 1,260) $ ( 24,650) Roll Forward of Allowance for Credit Losses Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 Foreign Foreign Foreign Foreign Corporate Government Corporate Corporate Government Corporate Securities Securities Securities Total Securities Securities Securities Total Beginning Balance $ ( 17,305) $ ( 519) $ ( 3,950) $ ( 21,774) $ - $ - $ - $ - Credit losses on securities where credit losses were not previously recorded ( 10,355) - ( 605) ( 10,960) ( 27,660) ( 519) ( 4,555) ( 32,734) Increases in allowance on previously - impaired securities ( 782) - ( 300) ( 1,082) ( 782) - ( 300) ( 1,082) Decreases in allowance on previously - impaired securities 3,431 212 693 4,336 3,431 212 693 4,336 Reduction in allowance due to disposals 2,758 215 670 3,643 2,758 215 670 3,643 Balance as of June 30, 2020 $ ( 22,253) $ ( 92) $ ( 3,492) $ ( 25,837) $ ( 22,253) $ ( 92) $ ( 3,492) $ ( 25,837) The Company recorded as net realized capital gains (losses) in the consolidated statements of operations and comprehensive income (loss) fair value re-measurements, allowances for credit losses per ASU 2016-13 and write-downs in the value of securities deemed to be impaired on an other-than-temporary basis in prior years as displayed in the table above. The proceeds and split between gross gains and losses, from sales of fixed maturity and equity securities, are presented in the table below for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Proceeds from sales of fixed maturity securities $ 371,459 $ 488,320 $ 599,737 $ 990,273 Gross gains from sales 19,870 21,355 34,734 35,356 Gross losses from sales ( 9,810) ( 11,736) ( 15,500) ( 39,813) Proceeds from sales of equity securities $ 193,350 $ 100,344 $ 474,663 $ 213,185 Gross gains from sales 5,803 18,172 18,107 20,756 Gross losses from sales ( 2,048) ( 1,898) ( 8,114) ( 32,081)

Reserve For Losses, LAE And Fut

Reserve For Losses, LAE And Future Policy Benefit Reserve	6 Months Ended
	Jun. 30, 2021
Reserve For Losses, LAE And Future Policy Benefit Reserve [Abstract]
Reserve For Losses, LAE And Future Policy Benefit Reserve	4. RESERVE FOR LOSSES, LAE AND FUTURE POLICY BENEFIT RESERVE Activity in the reserve for losses and LAE is summarized for the periods indicated: Six Months Ended June 30, (Dollars in thousands) 2021 2020 Gross reserves beginning of period $ 16,398,997 $ 13,611,313 Less reinsurance recoverables ( 1,843,691) ( 1,640,712) Net reserves beginning of period 14,555,306 11,970,601 Incurred related to: Current year 3,302,013 2,835,129 Prior years ( 4,453) 2,727 Total incurred losses and LAE 3,297,560 2,837,856 Paid related to: Current year 710,677 570,460 Prior years 1,394,838 1,579,931 Total paid losses and LAE 2,105,515 2,150,391 Foreign exchange/translation adjustment 35,651 ( 74,372) Net reserves end of period 15,783,002 12,583,694 Plus reinsurance recoverables 1,862,760 1,692,947 Gross reserves end of period $ 17,645,762 $ 14,276,641 (Some amounts may not reconcile due to rounding.) Current year incurred losses were $ 3,302,013 thousand and $ 2,835,129 thousand for the six months ended June 30, 2021 and 2020, respectively. The increase in current year incurred losses in 2021 compared to 2020 was primarily due to a $ 270,000 thousand increase in catastrophe losses and the impact of the increase in premiums earned. In addition, current year incurred losses for the three and six months ended June 30, 2020 included $ 159,978 thousand and $ 309,978 thousand of losses associated with the COVID-19 Pandemic which did not recur in 2021.

Fair Value

Fair Value	6 Months Ended
	Jun. 30, 2021
Fair Value [Abstract]
Fair Value	5. FAIR VALUE GAAP guidance regarding fair value measurements address how companies should measure fair value when they are required to use fair value measures for recognition or disclosure purposes under GAAP and provides a common definition of fair value to be used throughout GAAP. It defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly fashion between market participants at the measurement date. In addition, it establishes a three-level valuation hierarchy for the disclosure of fair value measurements. The valuation hierarchy is based on the transparency of inputs to the valuation of an asset or liability. The level in the hierarchy within which a given fair value measurement falls is determined based on the lowest level input that is significant to the measurement, with Level 1 being the highest priority and Level 3 being the lowest priority. The levels in the hierarchy are defined as follows: Level 1: Inputs to the valuation methodology are observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in an active market; Level 2: Inputs to the valuation methodology include quoted prices for similar assets and liabilities in active markets, and inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument; Level 3: Inputs to the valuation methodology are unobservable and significant to the fair value measurement. The Company’s fixed maturity and equity securities are primarily managed by third party investment asset managers. The investment asset managers managing publicly traded securities obtain prices from nationally recognized pricing services. These services seek to utilize market data and observations in their evaluation process. They use pricing applications that vary by asset class and incorporate available market information and when fixed maturity securities do not trade on a daily basis the services will apply available information through processes such as benchmark curves, benchmarking of like securities, sector groupings and matrix pricing. In addition, they use model processes, such as the Option Adjusted Spread model to develop prepayment and interest rate scenarios for securities that have prepayment features. The investment asset managers do not make any changes to prices received from either the pricing services or the investment brokers. In addition, the investment asset managers have procedures in place to review the reasonableness of the prices from the service providers and may request verification of the prices. In addition, the Company continually performs analytical reviews of price changes and tests the prices on a random basis to an independent pricing source. No material variances were noted during these price validation procedures. In limited situations, where financial markets are inactive or illiquid, the Company may use its own assumptions about future cash flows and risk-adjusted discount rates to determine fair value. At June 30, 2021, $ 1,525,734 thousand of fixed maturities, market value were fair valued using unobservable inputs. The majority of these fixed maturities were valued by investment managers’ valuation committees and many of these fair values were substantiated by valuations from independent third parties. The Company has procedures in place to evaluate these independent third party valuations. At December 31, 2020, $ 1,330,224 thousand of fixed maturities, market value were fair valued using unobservable inputs. The Company internally manages a public equity portfolio which had a fair value at June 30, 2021 and December 31, 2020 of $ 1,116,408 thousand and $ 784,746 thousand, respectively, and all prices were obtained from publicly published sources. Equity securities denominated in U.S. currency with quoted prices in active markets for identical assets are categorized as Level 1 since the quoted prices are directly observable. Equity securities traded on foreign exchanges are categorized as Level 2 due to the added input of a foreign exchange conversion rate to determine fair or market value. The Company uses foreign currency exchange rates published by nationally recognized sources. All categories of fixed maturity securities listed in the tables below are generally categorized as Level 2, since a particular security may not have traded but the pricing services are able to use valuation models with observable market inputs such as interest rate yield curves and prices for similar fixed maturity securities in terms of issuer, maturity and seniority. For foreign government securities and foreign corporate securities, the fair values provided by the third party pricing services in local currencies, and where applicable, are converted to U.S. dollars using currency exchange rates from nationally recognized sources. In addition to the valuations from investment managers, some of the fixed maturities with fair values categorized as Level 3 result when prices are not available from the nationally recognized pricing services. The asset managers may obtain non-binding price quotes for the securities from brokers. The single broker quotes are provided by market makers or broker-dealers who are recognized as market participants in the markets in which they are providing the quotes. The prices received from brokers are reviewed for reasonableness by the third party asset managers and the Company. If the broker quotes are for foreign denominated securities, the quotes are converted to U.S. dollars using currency exchange rates from nationally recognized sources. In limited circumstances when broker prices are not available for private placements, the Company will value the securities using comparable market information or receive fair values from investment managers. The composition and valuation inputs for the presented fixed maturities categories Level 1 and Level 2 are as follows: • U.S. Treasury securities and obligations of U.S. government agencies and corporations are primarily comprised of U.S. Treasury bonds and the fair value is based on observable market inputs such as quoted prices, reported trades, quoted prices for similar issuances or benchmark yields; • Obligations of U.S. states and political subdivisions are comprised of state and municipal bond issuances and the fair values are based on observable market inputs such as quoted market prices, quoted prices for similar securities, benchmark yields and credit spreads; • Corporate securities are primarily comprised of U.S. corporate and public utility bond issuances and the fair values are based on observable market inputs such as quoted market prices, quoted prices for similar securities, benchmark yields and credit spreads; • Asset-backed and mortgage-backed securities fair values are based on observable inputs such as quoted prices, reported trades, quoted prices for similar issuances or benchmark yields and cash flow models using observable inputs such as prepayment speeds, collateral performance and default spreads; • Foreign government securities are comprised of global non-U.S. sovereign bond issuances and the fair values are based on observable market inputs such as quoted market prices, quoted prices for similar securities and models with observable inputs such as benchmark yields and credit spreads and then, where applicable, converted to U.S. dollars using an exchange rate from a nationally recognized source; • Foreign corporate securities are comprised of global non-U.S. corporate bond issuances and the fair values are based on observable market inputs such as quoted market prices, quoted prices for similar securities and models with observable inputs such as benchmark yields and credit spreads and then, where applicable, converted to U.S. dollars using an exchange rate from a nationally recognized source. The following table presents the fair value measurement levels for all assets and liabilities, which the Company has recorded at fair value (fair and market value) as of the periods indicated: Fair Value Measurement Using: Quoted Prices in Active Significant Markets for Other Significant Identical Observable Unobservable Assets Inputs Inputs (Dollars in thousands) June 30, 2021 (Level 1) (Level 2) (Level 3) Assets: Fixed maturities, market value U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,275,758 $ - $ 1,275,758 $ - Obligations of U.S. States and political subdivisions 609,345 - 609,345 - Corporate securities 7,359,704 - 6,654,133 705,571 Asset-backed securities 3,169,417 - 2,354,141 815,276 Mortgage-backed securities Commercial 1,078,399 - 1,078,399 - Agency residential 2,290,267 - 2,290,267 - Non-agency residential 8,211 - 8,211 - Foreign government securities 1,553,961 - 1,553,961 - Foreign corporate securities 3,930,137 - 3,925,250 4,887 Total fixed maturities, market value 21,275,199 - 19,749,465 1,525,734 Equity securities, fair value 1,485,833 1,412,711 73,122 - The following table presents the fair value measurement levels for all assets and liabilities, which the Company has recorded at fair value as of the periods indicated: Fair Value Measurement Using: Quoted Prices in Active Significant Markets for Other Significant Identical Observable Unobservable Assets Inputs Inputs (Dollars in thousands) December 31, 2020 (Level 1) (Level 2) (Level 3) Assets: Fixed maturities, market value U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,367,106 $ - $ 1,367,106 $ - Obligations of U.S. States and political subdivisions 577,295 - 577,295 - Corporate securities 7,149,026 - 6,447,534 701,492 Asset-backed securities 2,565,802 - 1,942,769 623,033 Mortgage-backed securities Commercial 990,303 - 990,303 - Agency residential 2,267,739 - 2,267,739 - Non-agency residential 5,194 - 5,194 - Foreign government securities 1,645,375 - 1,645,375 - Foreign corporate securities 3,472,333 - 3,466,634 5,699 Total fixed maturities, market value 20,040,173 - 18,709,949 1,330,224 Equity securities, fair value 1,472,236 1,368,704 103,532 - In addition, $ 289,278 thousand and $ 224,698 thousand of investments within other invested assets on the consolidated balance sheets as of June 30, 2021 and December 31, 2020, respectively, are not included within the fair value hierarchy tables as the assets are measured at NAV as a practical expedient to determine fair value. The following tables present the activity under Level 3, fair value measurements using significant unobservable inputs for fixed maturities, for the periods indicated: Total Fixed Maturities, Market Value Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 Corporate Asset-Backed Foreign Corporate Asset-Backed Foreign (Dollars in thousands) Securities Securities Corporate Total Securities Securities Corporate Total Beginning balance fixed maturities at market value $ 704,542 $ 785,360 $ 5,598 $ 1,495,500 $ 701,492 $ 623,033 $ 5,699 $ 1,330,224 Total gains or (losses) (realized/unrealized) Included in earnings ( 13,761) 206 137 ( 13,418) ( 15,550) ( 3,962) 140 ( 19,372) Included in other comprehensive income (loss) 4,582 7,610 ( 85) 12,107 7,418 4,475 ( 36) 11,857 Purchases, issuances and settlements 10,208 22,100 ( 763) 31,545 12,211 191,730 ( 916) 203,025 Transfers in and/or (out) of Level 3 - - - - - - - - Ending balance $ 705,571 $ 815,276 $ 4,887 $ 1,525,734 $ 705,571 $ 815,276 $ 4,887 $ 1,525,734 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date $ ( 17,279) $ ( 4,915) $ - $ ( 22,194) $ ( 17,279) $ ( 4,915) $ - $ ( 22,194) (Some amounts may not reconcile due to rounding.) Total Fixed Maturities, Market Value Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 Corporate Asset-Backed Foreign Corporate Asset-Backed Foreign (Dollars in thousands) Securities Securities Corporate Total Securities Securities Corporate Total Beginning balance fixed maturities at market value $ 713,081 $ 238,631 $ - $ 951,712 $ 617,588 $ 153,641 $ 1,750 $ 772,979 Total gains or (losses) (realized/unrealized) Included in earnings ( 248) 121 ( 97) ( 224) ( 462) 125 ( 97) ( 434) Included in other comprehensive income (loss) ( 549) 18,092 ( 40) 17,503 ( 3,906) 2,210 ( 40) ( 1,736) Purchases, issuances and settlements 14,345 38,886 5,434 58,665 113,409 139,754 3,684 256,847 Transfers in and/or (out) of Level 3 ( 4,795) - 977 ( 3,818) ( 4,795) - 977 ( 3,818) Ending balance $ 721,834 $ 295,730 $ 6,274 $ 1,023,838 $ 721,834 $ 295,730 $ 6,274 $ 1,023,838 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date $ - $ - $ - $ - $ ( 539) $ - $ - $ ( 539) (Some amounts may not reconcile due to rounding.) Total Fixed Maturities, Fair Value Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 Foreign Foreign (Dollars in thousands) Corporate Total Corporate Total Beginning balance fixed maturities at market value $ 4,703 $ 4,703 $ 5,826 $ 5,826 Total gains or (losses) (realized/unrealized) Included in earnings ( 272) ( 272) ( 1,395) ( 1,395) Included in other comprehensive income (loss) - - - - Purchases, issuances and settlements - - - - Transfers in and/or (out) of Level 3 - - - - Ending balance $ 4,431 $ 4,431 $ 4,431 $ 4,431 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date $ - $ - $ - $ - (Some amounts may not reconcile due to rounding.) The following table presents the activity under Level 3, fair value measurements using significant unobservable inputs for equity securities, for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Common Stock Balance, beginning of period $ - $ - $ - $ - Total (gains) or losses (realized/unrealized) Included in earnings - - - - Included in other comprehensive income (loss) - - - - Purchases, issuances and settlements - 9,877 - 9,877 Transfers in and/or (out) of Level 3 - - - - Balance, end of period $ - $ 9,877 $ - $ 9,877 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to liabilities still held at the reporting date $ - $ - $ - $ - (Some amounts may not reconcile due to rounding.)

Earnings Per Common Share

Earnings Per Common Share	6 Months Ended
	Jun. 30, 2021
Earnings Per Common Share [Abstract]
Earnings Per Common Share	6. EARNINGS PER COMMON SHARE Basic earnings per share are calculated by dividing net income by the weighted average number of common shares outstanding. Diluted earnings per share reflect the potential dilution that would occur if options granted under various share-based compensation plans were exercised resulting in the issuance of common shares that would participate in the earnings of the entity. Net income (loss) per common share has been computed as per below, based upon weighted average common basic and dilutive shares outstanding. Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands, except per share amounts) 2021 2020 2021 2020 Net income (loss) per share: Numerator Net income (loss) $ 679,982 $ 190,880 $ 1,021,844 $ 207,492 Less: dividends declared-common shares and unvested common shares ( 62,045) ( 61,927) ( 124,274) ( 125,205) Undistributed earnings 617,937 128,953 897,570 82,287 Percentage allocated to common shareholders (1) 98.6 % 98.7 % 98.7 % 98.7 % 609,411 127,233 885,595 81,224 Add: dividends declared-common shareholders 61,245 61,148 122,659 123,637 Numerator for basic and diluted earnings per common share $ 670,656 $ 188,381 $ 1,008,254 $ 204,861 Denominator Denominator for basic earnings per weighted-average common shares 39,527 39,449 39,535 39,827 Effect of dilutive securities: Options 41 69 48 81 Denominator for diluted earnings per adjusted weighted-average common shares 39,567 39,519 39,582 39,908 Per common share net income (loss) Basic $ 16.97 $ 4.78 $ 25.50 $ 5.14 Diluted $ 16.95 $ 4.77 $ 25.47 $ 5.13 (1) Basic weighted-average common shares outstanding 39,527 39,449 39,535 39,827 Basic weighted-average common shares outstanding and unvested common shares expected to vest 40,080 39,983 40,069 40,348 Percentage allocated to common shareholders 98.6 % 98.7 % 98.7 % 98.7 % (Some amounts may not reconcile due to rounding.) There were no anti-diluted options outstanding for the three and six months ended June 30, 2021 and 2020. All outstanding options expire on or between February 22, 2022 and September 19, 2022.

Commitments And Contingencies

Commitments And Contingencies	6 Months Ended
	Jun. 30, 2021
Commitments And Contingencies [Abstract]
Commitments And Contingencies	7. COMMITMENTS AND CONTINGENCIES In the ordinary course of business, the Company is involved in lawsuits, arbitrations and other formal and informal dispute resolution procedures, the outcomes of which will determine the Company’s rights and obligations under insurance and reinsurance agreements. In some disputes, the Company seeks to enforce its rights under an agreement or to collect funds owing to it. In other matters, the Company is resisting attempts by others to collect funds or enforce alleged rights. These disputes arise from time to time and are ultimately resolved through both informal and formal means, including negotiated resolution, arbitration and litigation. In all such matters, the Company believes that its positions are legally and commercially reasonable. The Company considers the statuses of these proceedings when determining its reserves for unpaid loss and loss adjustment expenses. Aside from litigation and arbitrations related to these insurance and reinsurance agreements, the Company is not a party to any other material litigation or arbitration. The Company had one equity index put option contract at June 30, 2021, based on the Standard & Poor’s 500 (“S&P 500”) index. Based on historical index volatilities and trends and the June 30, 2021 S&P 500 index value, the Company estimates the probability that the equity index put option contract of the S&P 500 index falling below the strike price on the exercise date to be less than 0.1%. The theoretical maximum payout under this equity index put option contract would occur if on the exercise date the S&P 500 index value was zero. At June 30, 2021, the present value of the theoretical maximum payout using a 3% discount factor was $ 150,077 thousand. Conversely, if the contract had expired on June 30, 2021, with the S&P index at 4,297.50, there would have been no settlement amount. The Company has entered into separate annuity agreements with The Prudential Insurance of America (“The Prudential”) and an additional unaffiliated life insurance company in which the Company has either purchased annuity contracts or become the assignee of annuity proceeds that are meant to settle claim payment obligations in the future. In both instances, the Company would become contingently liable if either The Prudential or the unaffiliated life insurance company were unable to make payments related to the respective annuity contract. The table below presents the estimated cost to replace all such annuities for which the Company was contingently liable for the periods indicated: At June 30, At December 31, (Dollars in thousands) 2021 2020 The Prudential $ 139,236 $ 140,773 Unaffiliated life insurance company 33,492 35,128

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	6 Months Ended
	Jun. 30, 2021
Other Comprehensive Income (Loss) [Abstract]
Other Comprehensive Income (Loss)	8. OTHER COMPREHENSIVE INCOME (LOSS) The following table presents the components of comprehensive income (loss) in the consolidated statements of operations for the periods indicated: Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 (Dollars in thousands) Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized appreciation (depreciation) ("URA(D)") on securities - non-credit related $ 94,009 $ ( 9,838) $ 84,171 $ ( 235,157) $ 30,713 $ ( 204,444) Reclassification of net realized losses (gains) included in net income (loss) 3,118 ( 1,528) 1,590 ( 424) ( 1,652) ( 2,076) Foreign currency translation adjustments 38,022 ( 3,727) 34,295 29,034 ( 4,321) 24,713 Reclassification of benefit plan liability amortization included in net income (loss) 2,586 ( 543) 2,043 5,172 ( 1,086) 4,086 Total other comprehensive income (loss) $ 137,735 $ ( 15,636) $ 122,099 $ ( 201,375) $ 23,654 $ ( 177,721) Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 (Dollars in thousands) Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized appreciation (depreciation) ("URA(D)") on securities - non-credit related $ 620,926 $ ( 69,173) $ 551,753 $ 305,725 $ ( 33,371) $ 272,354 Reclassification of net realized losses (gains) included in net income (loss) ( 6,849) ( 408) ( 7,257) 31,328 ( 7,186) 24,142 Foreign currency translation adjustments 22,825 ( 2,239) 20,586 ( 35,898) 5,660 ( 30,238) Reclassification of benefit plan liability amortization included in net income (loss) 2,286 ( 480) 1,806 3,451 ( 725) 2,726 Total other comprehensive income (loss) $ 639,188 $ ( 72,300) $ 566,888 $ 304,606 $ ( 35,622) $ 268,984 The following table presents details of the amounts reclassified from AOCI for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, Affected line item within the statements of AOCI component 2021 2020 2021 2020 operations and comprehensive income (loss) (Dollars in thousands) URA(D) on securities $ 3,118 $ ( 6,849) $ ( 424) $ 31,328 Other net realized capital gains (losses) ( 1,528) ( 408) ( 1,652) ( 7,186) Income tax expense (benefit) $ 1,590 $ ( 7,257) $ ( 2,076) $ 24,142 Net income (loss) Benefit plan net gain (loss) $ 2,586 $ 2,286 $ 5,172 $ 3,451 Other underwriting expenses ( 543) ( 480) ( 1,086) ( 725) Income tax expense (benefit) $ 2,043 $ 1,806 $ 4,086 $ 2,726 Net income (loss) The following table presents the components of accumulated other comprehensive income (loss), net of tax, in the consolidated balance sheets for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Beginning balance of URA (D) on securities $ 431,878 $ 56,426 $ 724,159 $ 304,425 Current period change in URA (D) of investments - non-credit related 85,761 544,496 ( 206,520) 296,496 Ending balance of URA (D) on securities 517,639 600,922 517,639 600,922 Beginning balance of foreign currency translation adjustments ( 124,972) ( 252,541) ( 115,390) ( 201,717) Current period change in foreign currency translation adjustments 34,295 20,586 24,713 ( 30,238) Ending balance of foreign currency translation adjustments ( 90,677) ( 231,955) ( 90,677) ( 231,955) Beginning balance of benefit plan net gain (loss) ( 71,827) ( 73,636) ( 73,870) ( 74,556) Current period change in benefit plan net gain (loss) 2,043 1,806 4,086 2,726 Ending balance of benefit plan net gain (loss) ( 69,784) ( 71,830) ( 69,784) ( 71,830) Ending balance of accumulated other comprehensive income (loss) $ 357,178 $ 297,137 $ 357,178 $ 297,137 (Some amounts may not reconcile due to rounding.)

Credit Facilities

Credit Facilities	6 Months Ended
	Jun. 30, 2021
Credit Facilities [Abstract]
Credit Facilities	9. CREDIT FACILITIES The Company has three active credit facilities for a total commitment of up to $ 1,300,000 thousand and an additional credit facility for a total commitment of up to £ 52,175 thousand, providing for the issuance of letters of credit and/or unsecured revolving credit lines. The following table presents the interest and fees incurred in connection with these credit facilities for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Credit facility interest and fees incurred $ 70 $ 332 $ 175 $ 455 Loan interest and fees incurred - Federal Home Loan Bank 275 - 546 - Total interest and fees incurred $ 345 $ 332 $ 721 $ 455 The terms and outstanding amounts for each facility are discussed below: Group Credit Facility Effective May 26, 2016, Group, Everest Reinsurance (Bermuda), Ltd. (“Bermuda Re”) and Everest International Reinsurance, Ltd. (“Everest International”), both direct subsidiaries of Group, entered into a five year, $ 800,000 thousand senior credit facility with a syndicate of lenders, which amended and restated in its entirety the June 22, 2012, four year, $ 800,000 thousand senior credit facility. Both the May 26, 2016 and June 22, 2012 senior credit facilities, which have similar terms, are referred to as the “2016 Group Credit Facility”. Wells Fargo Corporation (“Wells Fargo Bank”) is the administrative agent for the 2016 Group Credit Facility, which consists of two tranches. Tranche one provides up to $ 200,000 thousand of unsecured revolving credit for liquidity and general corporate purposes, and for the issuance of unsecured standby letters of credit. Tranche two exclusively provides up to $ 600,000 thousand for the issuance of standby letters of credit on a collateralized basis. The interest on the revolving loans shall, at the Company’s option, be either (1) the Base Rate (as defined below) or (2) an adjusted London Interbank Offered Rate (“LIBOR”) plus a margin. The Base Rate is the higher of (a) the prime commercial lending rate established by Wells Fargo Bank, (b) the Federal Funds Rate plus 0.5% per annum or (c) the one month LIBOR Rate plus 1.0% per annum. The amount of margin and the fees payable for the Group Credit Facility depends on Group’s senior unsecured debt rating. Effective May 26, 2021, the term of the 2016 Group Credit Facility expired. The Company elected not to renew this facility to allow for the replacement by new credit facilities, including the 2021 Bermuda Re Wells Fargo Letter of Credit Facility, detailed below. As a result, Tranche One of the Group Credit Facility (unsecured revolving credit in the amount of $ 200,000 thousand) is no longer effective or available for use. The $, 600000 thousand of credit availability in Tranche two will be in run-off and able to support standby letters of credit currently in force through December 31, 2021. As of December 31, 2021, the entirety of the 2016 Group Credit Facility will have expired and will no longer be effective. This collateralized letter of credit capacity will be replaced with additional bilateral collateralized letters of credit. The Group Credit Facility requires Group to maintain a debt to capital ratio of not greater than 0.35 to 1 and to maintain a minimum net worth. Minimum net worth is an amount equal to the sum of $ 5,370,979 thousand plus 25% of consolidated net income for each of Group’s fiscal quarters, for which statements are available ending on or after March 31, 2016 and for which consolidated net income is positive, plus 25% of any increase in consolidated net worth during such period attributable to the issuance of ordinary and preferred shares, which at June 30, 2021, was $ 6,649,276 thousand. As of June 30, 2021, the Company was in compliance with all Group Credit Facility covenants. On March 25, 2020, Group borrowed $ 50,000 thousand under Tranche one of the credit facility as an unsecured revolving credit loan. The loan was fully paid off on June 26, 2020. The following table summarizes the outstanding letters of credit and/or borrowings for the periods indicated: (Dollars in thousands) At June 30, 2021 At December 31, 2020 Bank Commitment In Use Date of Expiry Commitment In Use Date of Expiry Wells Fargo Bank Group Credit Facility Tranche One $ - $ - $ 200,000 $ 164,242 12/31/2021 Tranche Two 600,000 402,284 12/31/2021 600,000 589,690 12/31/2021 Total Wells Fargo Bank Group Credit Facility $ 600,000 $ 402,284 $ 800,000 $ 753,932 Bermuda Re Wells Fargo Letter of Credit Facility Effective February 23, 2021, Bermuda Re entered into a letter of credit issuance facility with Wells Fargo referred to as the “2021 Bermuda Re Wells Fargo Letter of Credit Facility.” The Bermuda Re Wells Fargo Letter of Credit Facility originally provided for the issuance of up to $ 50,000 thousand of secured letters of credit. Effective May 5, 2021, the agreement was amended to provide for the issuance of up to $ 500,000 thousand of secured letters of credit. The following table summarizes the outstanding letters of credit for the periods indicated: (Dollars in thousands) At June 30, 2021 Bank Commitment In Use Date of Expiry Wells Fargo Bank Bilateral LOC Agreement $ 500,000 $ 404,421 12/31/2021 $ 500,000 $ 404,421 Bermuda Re Citibank Letter of Credit Facility Effective December 31, 2020, Bermuda Re renewed its letter of credit issuance facility with Citibank N.A. referred to as the “Bermuda Re Letter of Credit Facility”, which commitment is reconfirmed annually with updated fees. The current renewal of the Bermuda Re Letter of Credit Facility provides for the issuance of up to $ 200,000 thousand of secured letters of credit. The interest on drawn letters of credit shall be (A) 0.35% per annum of the principal amount of issued standard letters of credit (expiry of 15 months or less) and (B) 0.45% per annum of the principal amount of issued extended tenor letters of credit (expiry maximum of up to 60 months). The commitment fee on undrawn credit shall be 0.15% per annum. The following table summarizes the outstanding letters of credit for the periods indicated: (Dollars in thousands) At June 30, 2021 At December 31, 2020 Bank Commitment In Use Date of Expiry Commitment In Use Date of Expiry Citibank Bilateral Letter of Credit Agreement $ 200,000 $ 1,264 11/24/2021 $ 200,000 $ 4,425 02/28/2021 449 12/16/2021 3,672 11/24/2021 138,869 12/31/2021 448 12/16/2021 4,425 02/28/2022 115 12/20/2021 443 03/01/2022 136,383 12/31/2021 822 08/15/2022 39,619 12/30/2024 155 12/20/2022 821 08/15/2022 27,126 06/30/2025 - Total Citibank Bilateral Agreement $ 200,000 $ 173,553 $ 200,000 $ 185,483 Everest International Credit Facility Effective May 12, 2020, Everest International amended its credit facility with Lloyds Bank plc (“Everest International Credit Facility”). The current amendment of the Everest International Credit Facility provides up to £ 52,175 thousand for the issuance of standby letters of credit on a collateralized basis. The Company pays a commitment fee of 0.1% per annum on the average daily amount of the remainder of (1) the aggregate amount available under the facility and (2) the aggregate amount of drawings outstanding under the facility. The Company pays a credit commission fee of 0.35% per annum on drawings outstanding under the facility. The Everest International Credit Facility requires Group to maintain a debt to capital ratio of not greater than 0.35 to 1 and to maintain a minimum net worth. Minimum net worth is an amount equal to the sum of $ 6,393,047 thousand ( 70% of consolidated net worth as of December 31, 2019), plus 25% of consolidated net income for each of Group’s fiscal quarters, for which statements are available ending on or after January 1, 2020 and for which net income is positive, plus 25% of any increase in consolidated net worth of Group during such period attributable to the issuance of ordinary and preferred shares, which at June 30, 2021, was $ 6,786,229 thousand. As of June 30, 2021, the Company was in compliance with all Everest International Credit Facility requirements. The following table summarizes the outstanding letters of credit for the periods indicated: (Dollars in thousands) At June 30, 2021 At December 31, 2020 Bank Commitment In Use Date of Expiry Commitment In Use Date of Expiry Lloyd's Bank plc £ 52,175 £ 52,175 12/31/2024 £ 52,175 £ 52,175 12/31/2023 - - - - Total Lloyd's Bank Credit Facility £ 52,175 £ 52,175 £ 52,175 £ 52,175 Federal Home Loan Bank Membership Everest Reinsurance Company (“Everest Re”) is a member of the Federal Home Loan Bank of New York (“FHLBNY”), which allows Everest Re to borrow up to 10% of its statutory admitted assets. As of June 30, 2021, Everest Re had admitted assets of approximately $ 18,197,177 thousand which provides borrowing capacity of up to approximately $ 1,819,717 thousand. During 2020, Everest Re borrowed $ 400,000 thousand under its FHLBNY capacity. The borrowings have interest payable at an interest rate of 0.35%. As of June 30, 2021, $ 310,000 thousand of these borrowings remain outstanding, with maturities in November December 2021 4.5% of borrowed funds be used to acquire additional membership stock.

Collateralized Reinsurance And

Collateralized Reinsurance And Trust Agreements	6 Months Ended
	Jun. 30, 2021
Collateralized Reinsurance And Trust Agreements [Abstract]
Collateralized Reinsurance And Trust Agreements	10. COLLATERALIZED REINSURANCE AND TRUST AGREEMENTS Certain subsidiaries of Group have established trust agreements, which effectively use the Company’s investments as collateral, as security for assumed losses payable to certain non-affiliated ceding companies. At June 30, 2021, the total amount on deposit in trust accounts was $ 1,418,185 thousand. The Company reinsures some of its catastrophe exposures with the segregated accounts of Mt. Logan Re. Mt. Logan Re is a Collateralized insurer registered in Bermuda and 100% of the voting common shares are owned by Group. Each segregated account invests predominantly in a diversified set of catastrophe exposures, diversified by risk/peril and across different geographic regions globally. The following table summarizes the premiums and losses that are ceded by the Company to Mt. Logan Re segregated accounts and assumed by the Company from Mt. Logan Re segregated accounts. Three Months Ended Six Months Ended June 30, June 30, Mt. Logan Re Segregated Accounts 2021 2020 2021 2020 (Dollars in thousands) Ceded written premiums $ 56,183 $ 48,522 $ 155,293 $ 158,710 Ceded earned premiums 71,422 71,143 149,529 161,693 Ceded losses and LAE 31,052 40,936 111,895 86,051 Assumed written premiums 2,741 2,795 5,217 5,554 Assumed earned premiums 2,741 2,795 5,217 5,554 Assumed losses and LAE - - - - Each segregated account is permitted to assume net risk exposures equal to the amount of its available posted collateral, which in the aggregate was $ 831,634 thousand and $ 806,564 thousand at June 30, 2021 and December 31, 2020, respectively. Of this amount, Group had investments recorded at $ 67,881 thousand and $ 67,645 thousand at June 30, 2021 and December 31, 2020, respectively, in the segregated accounts. Effective April 1, 2018, the Company entered into a retroactive reinsurance transaction with one of the Mt. Logan Re segregated accounts to retrocede $ 269,198 thousand of casualty reserves held by Bermuda Re related to accident years 2002 through 2015. As consideration for entering the agreement, the Company transferred cash of $ 252,000 thousand to the Mt. Logan Re segregated account. The maximum liability to be retroceded under the agreement will be $ 319,000 thousand. The Company will retain liability for any amounts exceeding the maximum liability. As of June 30, 2021 and December 21, 2020, the Company has a reinsurance recoverable of $ 228,727 thousand and $ 254,907 thousand, respectively. In addition, the Company has a deferred gain liability of $ 36,064 thousand and $ 38,782 thousand as of June 30, 2021 and December 31, 2020, respectively, reported in other liabilities. The Company entered into various collateralized reinsurance agreements with Kilimanjaro Re Limited (“Kilimanjaro”), a Bermuda based special purpose reinsurer, to provide the Company with catastrophe reinsurance coverage. These agreements are multi-year reinsurance contracts which cover named storm and earthquake events. The table below summarizes the various agreements. (Dollars in thousands) Class Description Effective Date Expiration Date Limit Series 2017-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/13/2017 4/13/2022 50,000 Series 2017-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/13/2017 4/13/2022 75,000 Series 2017-1 Class C-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/13/2017 4/13/2022 175,000 Series 2018-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/6/2022 62,500 Series 2018-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/6/2022 200,000 Series 2018-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/5/2023 62,500 Series 2018-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/5/2023 200,000 Series 2019-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2023 150,000 Series 2019-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2023 275,000 Series 2019-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2024 150,000 Series 2019-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2024 275,000 Series 2020-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 150,000 Series 2020-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 85,000 Series 2020-1 Class C-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 85,000 Series 2020-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 150,000 Series 2020-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 90,000 Series 2020-1 Class C-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 90,000 Total available limit as of June 30, 2021 $ 2,325,000 Recoveries under these collateralized reinsurance agreements with Kilimanjaro are primarily dependent on estimated industry level insured losses from covered events, as well as, the geographic location of the events. The estimated industry level of insured losses is obtained from published estimates by an independent recognized authority on insured property losses. Currently, none of the published insured loss estimates for catastrophe events during the applicable covered periods of the various agreements have exceeded the single event retentions or aggregate retentions under the terms of the agreements that would result in a recovery. Kilimanjaro has financed the various property catastrophe reinsurance coverages by issuing catastrophe bonds to unrelated, external investors. The proceeds from the issuance of the Notes listed below are held in reinsurance trusts throughout the duration of the applicable reinsurance agreements and invested solely in U.S. government money market funds with a rating of at least “AAAm” by Standard & Poor’s. (Dollars in thousands) Note Series Issue Date Maturity Date Amount Series 2017-1 Class A-2 4/13/2017 4/13/2022 50,000 Series 2017-1 Class B-2 4/13/2017 4/13/2022 75,000 Series 2017-1 Class C-2 4/13/2017 4/13/2022 175,000 Series 2018-1 Class A-1 4/30/2018 5/6/2022 62,500 Series 2018-1 Class B-1 4/30/2018 5/6/2022 200,000 Series 2018-1 Class A-2 4/30/2018 5/5/2023 62,500 Series 2018-1 Class B-2 4/30/2018 5/5/2023 200,000 Series 2019-1 Class A-1 12/12/2019 12/19/2023 150,000 Series 2019-1 Class B-1 12/12/2019 12/19/2023 275,000 Series 2019-1 Class A-2 12/12/2019 12/19/2024 150,000 Series 2019-1 Class B-2 12/12/2019 12/19/2024 275,000 Series 2020-1 Class A-1 4/8/2021 4/21/2025 150,000 Series 2020-1 Class B-1 4/8/2021 4/21/2025 85,000 Series 2020-1 Class C-1 4/8/2021 4/21/2025 85,000 Series 2020-1 Class A-2 4/8/2021 4/20/2026 150,000 Series 2020-1 Class B-2 4/8/2021 4/20/2026 90,000 Series 2020-1 Class C-2 4/8/2021 4/20/2026 90,000

Senior Notes

Senior Notes	6 Months Ended
	Jun. 30, 2021
Senior Notes [Abstract]
Senior Notes	11. SENIOR NOTES The table below displays Everest Reinsurance Holdings’ (“Holdings”) outstanding senior notes. Market value is based on quoted market prices, but due to limited trading activity, these senior notes are considered Level 2 in the fair value hierarchy. June 30, 2021 December 31, 2020 Consolidated Balance Consolidated Balance (Dollars in thousands) Date Issued Date Due Principal Amounts Sheet Amount Market Value Sheet Amount Market Value 4.868% Senior notes 6/5/2014 6/1/2044 400,000 $ 397,254 $ 505,284 $ 397,194 $ 528,000 3.5% Senior notes 10/07/2020 10/15/2050 1,000,000 979,784 1,068,990 979,524 1,138,100 On June 5, 2014, Holdings issued $ 400,000 thousand of 30 year senior notes with an interest coupon rate of 4.868%, which will mature on June 1, 2044. Interest is paid semi-annually on June 1 and December 1 of each year. On October 7, 2020, Holdings issued $ 1,000,000 thousand of 30 year senior notes with an interest coupon rate of 3.50%, which will mature on October 15, 2050. Interest is paid semi-annually on April 15 and October 15 of each year. Interest expense incurred in connection with these senior notes is as follows for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars In thousands 2021 2020 2021 2020 Interest expense incurred 4.868% Senior notes $ 4,868 $ 4,868 $ 9,736 $ 9,736 Interest expense incurred 3.5% Senior notes 8,805 - 17,610 -

Long Term Subordinated Notes

Long Term Subordinated Notes	6 Months Ended
	Jun. 30, 2021
Long Term Subordinated Notes [Abstract]
Long Term Subordinated Notes	12. LONG TERM SUBORDINATED NOTES The table below displays Holdings’ outstanding fixed to floating rate long term subordinated notes. Market value is based on quoted market prices, but due to limited trading activity, these subordinated notes are considered Level 2 in the fair value hierarchy. Maturity Date June 30, 2021 December 31, 2020 Original Consolidated Balance Market Consolidated Balance Market (Dollars in thousands) Date Issued Principal Amount Scheduled Final Sheet Amount Value Sheet Amount Value Long term subordinated notes 4/26/2007 $ 400,000 5/15/2037 5/1/2067 $ 223,724 $ 214,772 $ 223,674 $ 206,447 During the fixed rate interest period from May 3, 2007 through May 14, 2017, interest was at the annual rate of 6.6%, payable semi-annually in arrears on November 15 and May 15 of each year, commencing on November 15, 2007. During the floating rate interest period from May 15, 2017 through maturity, interest will be based on the 3 month LIBOR plus 238.5 basis points, reset quarterly, payable quarterly in arrears on February 15, May 15, August 15 and November 15 of each year, subject to Holdings’ right to defer interest on one or more occasions for up to ten 2.54%. Holdings may redeem the long term subordinated notes on or after May 15, 2017, in whole or in part at 100% of the principal amount plus accrued and unpaid interest; however, redemption on or after the scheduled maturity date and prior to May 1, 2047 is subject to a replacement capital covenant. This covenant is for the benefit of certain senior note holders and it mandates that Holdings receive proceeds from the sale of another subordinated debt issue, of at least similar size, before it may redeem the subordinated notes. Effective upon the maturity of the Company’s 5.40% senior notes on October 15, 2014, the Company’s 4.868% senior notes, due on June 1, 2044, have become the Company’s long term indebtedness that ranks senior to the long term subordinated notes. The Company repurchased and retired $ 11,483 thousand and $ 13,183 thousand of its outstanding long term subordinated notes during the three and six months ended June 30, 2020, respectively. The Company realized a gain of $ 2,034 thousand and $ 2,536 thousand from the repurchase of the long term subordinated notes for the three and six months ended June 30, 2020, respectively. No repurchases of debt were made during the three and six months ended June 30, 2021. On March 19, 2009, Group announced the commencement of a cash tender offer for any and all of the 6.60% fixed to floating rate long term subordinated notes. Upon expiration of the tender offer, the Company had reduced its outstanding debt by $ 161,441 thousand. In addition, during 2020, the Company repurchased and retired $ 13,183 thousand of the notes. Interest expense incurred in connection with these long term subordinated notes is as follows for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Interest expense incurred $ 1,460 $ 2,000 $ 2,922 $ 4,539

Segment Reporting

Segment Reporting	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Segment Reporting	13. SEGMENT REPORTING The Reinsurance operation writes worldwide property and casualty reinsurance and specialty lines of business, on both a treaty and facultative basis, through reinsurance brokers, as well as directly with ceding companies. Business is written in the U.S., Bermuda, and Ireland offices, as well as, through branches in Canada, Singapore, the United Kingdom and Switzerland. The Insurance operation writes property and casualty insurance directly and through brokers, surplus lines brokers and general agents within the U.S., Canada and Europe through its offices in the U.S., Canada, Ireland and branches in Switzerland and the Netherlands. These segments are managed independently, but conform with corporate guidelines with respect to pricing, risk management, control of aggregate catastrophe exposures, capital, investments and support operations. Management generally monitors and evaluates the financial performance of these operating segments based upon their underwriting results. Underwriting results include earned premium less losses and loss adjustment expenses (“LAE”) incurred, commission and brokerage expenses and other underwriting expenses. The Company measures its underwriting results using ratios, in particular loss, commission and brokerage and other underwriting expense ratios, which, respectively, divide incurred losses, commissions and brokerage and other underwriting expenses by premiums earned. The Company does not maintain separate balance sheet data for its operating segments. Accordingly, the Company does not review and evaluate the financial results of its operating segments based upon balance sheet data. The following tables present the underwriting results for the operating segments for the periods indicated: Three Months Ended Six Months Ended Reinsurance June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Gross written premiums $ 2,148,235 $ 1,538,348 $ 4,207,250 $ 3,316,119 Net written premiums 2,059,919 1,424,089 3,972,868 3,037,183 Premiums earned $ 1,920,801 $ 1,502,256 $ 3,698,253 $ 2,987,476 Incurred losses and LAE 1,168,139 1,005,677 2,440,045 2,026,319 Commission and brokerage 473,258 387,339 881,982 757,695 Other underwriting expenses 47,065 39,698 99,061 83,837 Underwriting gain (loss) $ 232,339 $ 69,542 $ 277,165 $ 119,625 Three Months Ended Six Months Ended Insurance June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Gross written premiums $ 1,041,905 $ 830,990 $ 1,914,323 $ 1,624,090 Net written premiums 749,492 593,389 1,390,479 1,181,774 Premiums earned $ 637,571 $ 540,149 $ 1,247,984 $ 1,091,743 Incurred losses and LAE 418,002 401,339 857,515 811,537 Commission and brokerage 84,490 78,977 164,777 157,143 Other underwriting expenses 93,779 78,432 184,014 163,153 Underwriting gain (loss) $ 41,300 $ ( 18,599) $ 41,678 $ ( 40,090) The following table reconciles the underwriting results for the operating segments to income before taxes as reported in the consolidated statements of operations and comprehensive income (loss) for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Underwriting gain (loss) $ 273,639 $ 50,943 $ 318,843 $ 79,535 Net investment income 407,095 38,083 667,508 185,883 Net realized capital gains (losses) 104,109 184,648 143,011 ( 25,940) Corporate expenses ( 16,168) ( 8,733) ( 28,546) ( 18,566) Interest, fee and bond issue cost amortization expense ( 15,607) ( 7,253) ( 31,246) ( 14,836) Other income (expense) 7,114 ( 20,621) 63,707 ( 12,631) Income (loss) before taxes $ 760,181 $ 237,067 $ 1,133,276 $ 193,445 The Company produces business in the U.S., Bermuda and internationally. The net income deriving from and assets residing in the individual foreign countries in which the Company writes business are not identifiable in the Company’s financial records. Based on gross written premium, the table below presents the largest country, other than the U.S., in which the Company writes business, for the periods indicated: Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 United Kingdom gross written premium $ 249,314 $ 236,100 $ 615,462 $ 542,808 No other country represented more than 5% of the Company’s revenues.

Share-Based Compensation Plans

Share-Based Compensation Plans	6 Months Ended
	Jun. 30, 2021
Share-Based Compensation Plans [Abstract]
Share-Based Compensation Plans	14. SHARE-BASED COMPENSATION PLANS For the three months ended June 30, 2021, a total of 2,275 restricted stock awards were granted: 2,275 restricted share awards were granted on May 12, 2021 with a fair value of $ 264.845 per share. For the six months ended June 30, 2021, a total of 207,541 restricted stock awards were granted: 194,610, 10,656 and 2,275 restricted share awards were granted on February 23, 2021, February 24, 2021 and May 12, 2021, with a fair value of $ 242.24 per share, $ 244.445 per share and $ 264.845 per share, respectively. Additionally, 22,205 performance share unit awards were granted on February 23, 2021, with a fair value of $ 242.24 per unit.

Retirement Benefits

Retirement Benefits	6 Months Ended
	Jun. 30, 2021
Retirement Benefits [Abstract]
Retirement Benefits	15. RETIREMENT BENEFITS The Company maintains both qualified and non-qualified defined benefit pension plans for its U.S. employees employed prior to April 1, 2010. Generally, the Company computes the benefits based on average earnings over a period prescribed by the plans and credited length of service. The Company’s non-qualified defined benefit pension plan provided compensating pension benefits for participants whose benefits have been curtailed under the qualified plan due to Internal Revenue Code limitations. Effective January 1, 2018, participants of the Company’s non-qualified defined benefit pension plan may no longer accrue additional service benefits. Net periodic benefit cost for U.S. employees included the following components for the periods indicated: Pension Benefits Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Service cost $ 2,738 $ 2,041 $ 5,476 $ 6,052 Interest cost 1,999 2,563 3,998 5,046 Expected return on plan assets ( 5,580) ( 5,197) ( 11,161) ( 10,394) Amortization of net (income) loss 2,731 2,462 5,461 3,675 Net periodic benefit cost $ 1,888 $ 1,869 $ 3,774 $ 4,379 Other Benefits Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Service cost $ 281 $ 311 $ 564 $ 452 Interest cost 181 215 362 429 Amortization of prior service cost ( 144) ( 176) ( 289) ( 224) Net periodic benefit cost $ 318 $ 350 $ 637 $ 657 The service cost component of net periodic benefit costs is included within other underwriting expenses on the consolidated statement of operations and comprehensive income (loss). In accordance with ASU 2017-07, other staff compensation costs are also primarily recorded within this line item. The Company did no t make any contributions to the qualified pension benefit plan for the three and six months ended June 30, 2021 and 2020, respectively.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2021
Income Taxes [Abstract]
Income Taxes	16. INCOME TAXES The Company is domiciled in Bermuda and has significant subsidiaries and/or branches in Canada, Ireland, the Netherlands, Singapore, Switzerland, the United Kingdom, and the United States. The Company’s Bermuda domiciled subsidiaries are exempt from income taxation under Bermuda law until 2035. The Company’s non-Bermudian subsidiaries and branches are subject to income taxation at varying rates in their respective domiciles. The Company generally applies the estimated Annualized Effective Tax Rate (“AETR”) approach for calculating its tax provision for interim periods as prescribed by ASC 740-270, Interim Reporting. Under the AETR approach, the estimated annualized effective tax rate is applied to the interim year-to-date pre-tax income/loss to determine the income tax expense or benefit for the year-to-date period. The tax expense or benefit for the quarter represents the difference between the year-to-date tax expense or benefit for the current year-to-date period less such amount for the immediately preceding year-to-date period. Management considers the impact of all known events in its estimation of the Company’s annual pre-tax income/loss and annualized effective tax rate.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	17. SUBSEQUENT EVENTS The Company has evaluated known recognized and non-recognized subsequent events. Between July and August 2021, numerous wildfires have occurred in the western United States and severe floods have occurred in Central Europe, both of which have caused widespread damage. The Company is in the preliminary stage of assessing the impact of these events on the Company’s financial results for the third quarter of 2021. It is difficult at this time to provide an accurate estimate of the financial impact of these events, including as a result of the preliminary nature of the information available and provided thus far by industry participants, the magnitude and recent occurrence of the events and other factors. The estimated losses for these events will be reported in the Company’s third quarter 2021 financial results. However, the Company anticipates that the losses from these events will negatively impact third quarter 2021 financial statements.

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2021
Investments [Abstract]
Summary Of Unrealized Appreciation (Depreciation) Of Available For Sale, Fixed Maturity And Equity Security Investments	At June 30, 2021 Amortized Allowance for Unrealized Unrealized Market (Dollars in thousands) Cost Credit Losses Appreciation Depreciation Value Fixed maturity securities U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,259,149 $ - $ 29,365 $ ( 12,756) $ 1,275,758 Obligations of U.S. states and political subdivisions 574,398 - 35,933 ( 986) 609,345 Corporate securities 7,155,688 ( 18,475) 285,509 ( 63,018) 7,359,704 Asset-backed securities 3,141,971 ( 4,915) 35,316 ( 2,955) 3,169,417 Mortgage-backed securities Commercial 1,026,809 - 55,125 ( 3,535) 1,078,399 Agency residential 2,255,348 - 47,124 ( 12,205) 2,290,267 Non-agency residential 8,220 - 6 ( 15) 8,211 Foreign government securities 1,494,989 - 80,268 ( 21,296) 1,553,961 Foreign corporate securities 3,802,145 ( 1,260) 167,015 ( 37,763) 3,930,137 Total fixed maturity securities $ 20,718,717 $ ( 24,650) $ 735,661 $ ( 154,529) $ 21,275,199 At December 31, 2020 Amortized Allowance for Unrealized Unrealized Market (Dollars in thousands) Cost Credit Losses Appreciation Depreciation Value Fixed maturity securities U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,325,156 $ - $ 49,084 $ ( 7,134) $ 1,367,106 Obligations of U.S. states and political subdivisions 543,895 - 34,654 ( 1,254) 577,295 Corporate securities 6,824,800 ( 1,220) 380,677 ( 55,231) 7,149,026 Asset-backed securities 2,540,809 - 30,691 ( 5,698) 2,565,802 Mortgage-backed securities Commercial 915,923 - 75,275 ( 895) 990,303 Agency residential 2,206,139 - 64,663 ( 3,063) 2,267,739 Non-agency residential 5,187 - 9 ( 2) 5,194 Foreign government securities 1,565,260 ( 22) 102,587 ( 22,450) 1,645,375 Foreign corporate securities 3,297,898 ( 503) 204,023 ( 29,085) 3,472,333 Total fixed maturity securities $ 19,225,067 $ ( 1,745) $ 941,663 $ ( 124,812) $ 20,040,173
Summary Of Amortized Cost And Market Value Of Fixed Maturity Securities, By Contractual Maturity	At June 30, 2021 At December 31, 2020 Amortized Market Amortized Market (Dollars in thousands) Cost Value Cost Value Fixed maturity securities – available for sale: Due in one year or less $ 1,628,113 $ 1,638,768 $ 1,365,793 $ 1,374,674 Due after one year through five years 6,432,847 6,618,429 6,529,189 6,774,785 Due after five years through ten years 4,890,259 5,091,435 4,414,211 4,751,903 Due after ten years 1,335,150 1,380,273 1,247,816 1,309,773 Asset-backed securities 3,141,971 3,169,417 2,540,809 2,565,802 Mortgage-backed securities: Commercial 1,026,809 1,078,399 915,923 990,303 Agency residential 2,255,348 2,290,267 2,206,139 2,267,739 Non-agency residential 8,220 8,211 5,187 5,194 Total fixed maturity securities $ 20,718,717 $ 21,275,199 $ 19,225,067 $ 20,040,173
Summary Of Changes In Net Unrealized Appreciation (Depreciation) For The Company's Investments	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Increase (decrease) during the period between the market value and cost of investments carried at market value, and deferred taxes thereon: Fixed maturity securities $ 97,127 $ 614,077 $ ( 235,581) $ 337,053 Change in unrealized appreciation (depreciation), pre-tax 97,127 614,077 ( 235,581) 337,053 Deferred tax benefit (expense) ( 11,366) ( 69,581) 29,061 ( 40,557) Change in unrealized appreciation (depreciation), net of deferred taxes, included in shareholders’ equity $ 85,761 $ 544,496 $ ( 206,520) $ 296,496
Summary Of Aggregate Market Value And Gross Unrealized Depreciation Of Fixed Maturity And Equity Securities, By Security Type	Duration of Unrealized Loss at June 30, 2021 By Security Type Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities - available for sale U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 341,846 $ ( 12,494) $ 2,620 $ ( 262) $ 344,466 $ ( 12,756) Obligations of U.S. states and political subdivisions 23,662 ( 986) - - 23,662 ( 986) Corporate securities 1,598,159 ( 61,141) 37,936 ( 1,877) 1,636,095 ( 63,018) Asset-backed securities 710,904 ( 2,955) - - 710,904 ( 2,955) Mortgage-backed securities Commercial 134,941 ( 3,535) - - 134,941 ( 3,535) Agency residential 1,020,232 ( 11,327) 43,983 ( 878) 1,064,215 ( 12,205) Non-agency residential 1,309 ( 15) - - 1,309 ( 15) Foreign government securities 304,722 ( 20,686) 3,107 ( 610) 307,829 ( 21,296) Foreign corporate securities 861,693 ( 34,534) 30,035 ( 3,229) 891,728 ( 37,763) Total fixed maturity securities $ 4,997,468 $ ( 147,673) $ 117,681 $ ( 6,856) $ 5,115,149 $ ( 154,529) Duration of Unrealized Loss at December 31, 2020 By Security Type Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities - available for sale U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 135,190 $ ( 7,134) $ - $ - $ 135,190 $ ( 7,134) Obligations of U.S. states and political subdivisions 19,524 ( 999) 4,059 ( 255) 23,583 ( 1,254) Corporate securities 669,755 ( 26,159) 247,962 ( 29,072) 917,717 ( 55,231) Asset-backed securities 235,566 ( 4,768) 85,595 ( 930) 321,161 ( 5,698) Mortgage-backed securities Commercial 53,511 ( 578) 6,592 ( 317) 60,103 ( 895) Agency residential 434,447 ( 2,016) 50,353 ( 1,047) 484,800 ( 3,063) Non-agency residential 185 ( 2) - - 185 ( 2) Foreign government securities 114,755 ( 8,813) 150,812 ( 13,637) 265,567 ( 22,450) Foreign corporate securities 354,548 ( 17,489) 115,595 ( 11,596) 470,143 ( 29,085) Total fixed maturity securities $ 2,017,481 $ ( 67,958) $ 660,968 $ ( 56,854) $ 2,678,449 $ ( 124,812)
Summary Of Aggregate Market Value And Gross Unrealized Depreciation Of Fixed Maturity And Equity Securities, By Contractual Maturity	Duration of Unrealized Loss at June 30, 2021 By Maturity Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities Due in one year or less $ 260,687 $ ( 15,951) $ 5,846 $ ( 471) $ 266,533 $ ( 16,422) Due in one year through five years 1,385,520 ( 51,928) 48,824 ( 3,048) 1,434,344 ( 54,976) Due in five years through ten years 1,153,553 ( 48,557) 19,028 ( 2,459) 1,172,581 ( 51,016) Due after ten years 330,322 ( 13,405) - - 330,322 ( 13,405) Asset-backed securities 710,904 ( 2,955) - - 710,904 ( 2,955) Mortgage-backed securities 1,156,482 ( 14,877) 43,983 ( 878) 1,200,465 ( 15,755) Total fixed maturity securities $ 4,997,468 $ ( 147,673) $ 117,681 $ ( 6,856) $ 5,115,149 $ ( 154,529) Duration of Unrealized Loss at December 31, 2020 By Maturity Less than 12 months Greater than 12 months Total Gross Gross Gross Unrealized Unrealized Unrealized (Dollars in thousands) Market Value Depreciation Market Value Depreciation Market Value Depreciation Fixed maturity securities Due in one year or less $ 96,144 $ ( 4,942) $ 112,419 $ ( 12,071) $ 208,563 $ ( 17,013) Due in one year through five years 653,816 ( 32,469) 283,866 ( 21,319) 937,682 ( 53,788) Due in five years through ten years 422,517 ( 19,392) 49,749 ( 2,034) 472,266 ( 21,426) Due after ten years 121,295 ( 3,791) 72,394 ( 19,136) 193,689 ( 22,927) Asset-backed securities 235,566 ( 4,768) 85,595 ( 930) 321,161 ( 5,698) Mortgage-backed securities 488,143 ( 2,596) 56,945 ( 1,364) 545,088 ( 3,960) Total fixed maturity securities $ 2,017,481 $ ( 67,958) $ 660,968 $ ( 56,854) $ 2,678,449 $ ( 124,812)
Summary Of Components Of Net Investment Income	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Fixed maturities $ 148,262 $ 133,918 $ 289,178 $ 271,842 Equity securities 3,493 3,662 8,331 7,183 Short-term investments and cash 773 1,687 953 3,862 Other invested assets: Limited partnerships 239,966 ( 88,254) 354,299 ( 66,686) Other 25,855 ( 2,962) 31,874 ( 16,033) Gross investment income before adjustments 418,349 48,051 684,635 200,168 Funds held interest income (expense) 3,287 2,021 11,253 10,237 Future policy benefit reserve income (expense) ( 170) ( 303) ( 461) ( 514) Gross investment income 421,466 49,769 695,427 209,891 Investment expenses ( 14,371) ( 11,686) ( 27,919) ( 24,008) Net investment income $ 407,095 $ 38,083 $ 667,508 $ 185,883
Summary Of Components Of Net Realized Capital Gains (Losses)	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Fixed maturity securities, market value: Allowance for credit losses $ ( 15,927) $ ( 4,063) $ ( 22,904) $ ( 25,837) Gains (losses) from sales 10,060 9,619 19,234 ( 4,457) Fixed maturity securities, fair value: Gains (losses) from sales - - - - Gains (losses) from fair value adjustments - ( 272) - ( 1,395) Equity securities, fair value: Gains (losses) from sales 3,755 16,274 9,993 ( 11,325) Gains (losses) from fair value adjustments 103,525 161,694 132,581 17,691 Other invested assets 2,748 1,293 4,094 ( 1,034) Short-term investments gain (loss) ( 52) 103 13 417 Total net realized capital gains (losses) $ 104,109 $ 184,648 $ 143,011 $ ( 25,940) Roll Forward of Allowance for Credit Losses Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 Foreign Foreign Foreign Foreign Corporate Asset-Backed Government Corporate Corporate Asset-Backed Government Corporate Securities Securities Securities Securities Total Securities Securities Securities Securities Total (Dollars in thousands) Beginning Balance $ ( 3,603) $ ( 4,915) $ - $ ( 205) $ ( 8,723) $ ( 1,220) $ - $ ( 22) $ ( 503) $ ( 1,745) Credit losses on securities where credit losses were not previously recorded ( 13,537) - - ( 1,055) ( 14,592) ( 15,920) ( 4,915) - ( 1,055) ( 21,890) Increases in allowance on previously - impaired securities ( 1,468) - - - ( 1,468) ( 1,468) - - - ( 1,468) Decreases in allowance on previously - impaired securities - - - - - - - - - - Reduction in allowance due to disposals 133 - - - 133 133 - 22 298 453 Balance as of June 30, 2021 $ ( 18,475) $ ( 4,915) $ - $ ( 1,260) $ ( 24,650) $ ( 18,475) $ ( 4,915) $ - $ ( 1,260) $ ( 24,650) Roll Forward of Allowance for Credit Losses Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 Foreign Foreign Foreign Foreign Corporate Government Corporate Corporate Government Corporate Securities Securities Securities Total Securities Securities Securities Total Beginning Balance $ ( 17,305) $ ( 519) $ ( 3,950) $ ( 21,774) $ - $ - $ - $ - Credit losses on securities where credit losses were not previously recorded ( 10,355) - ( 605) ( 10,960) ( 27,660) ( 519) ( 4,555) ( 32,734) Increases in allowance on previously - impaired securities ( 782) - ( 300) ( 1,082) ( 782) - ( 300) ( 1,082) Decreases in allowance on previously - impaired securities 3,431 212 693 4,336 3,431 212 693 4,336 Reduction in allowance due to disposals 2,758 215 670 3,643 2,758 215 670 3,643 Balance as of June 30, 2020 $ ( 22,253) $ ( 92) $ ( 3,492) $ ( 25,837) $ ( 22,253) $ ( 92) $ ( 3,492) $ ( 25,837)
Summary Of Gross Gains (Losses) From Sales Of Fixed Maturity And Equity Securities	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Proceeds from sales of fixed maturity securities $ 371,459 $ 488,320 $ 599,737 $ 990,273 Gross gains from sales 19,870 21,355 34,734 35,356 Gross losses from sales ( 9,810) ( 11,736) ( 15,500) ( 39,813) Proceeds from sales of equity securities $ 193,350 $ 100,344 $ 474,663 $ 213,185 Gross gains from sales 5,803 18,172 18,107 20,756 Gross losses from sales ( 2,048) ( 1,898) ( 8,114) ( 32,081)

Reserve For Losses, LAE And F_2

Reserve For Losses, LAE And Future Policy Benefit Reserve (Tables)	6 Months Ended
	Jun. 30, 2021
Reserve For Losses, LAE And Future Policy Benefit Reserve [Abstract]
Summary Of Activity In The Reserve For Losses And LAE	Six Months Ended June 30, (Dollars in thousands) 2021 2020 Gross reserves beginning of period $ 16,398,997 $ 13,611,313 Less reinsurance recoverables ( 1,843,691) ( 1,640,712) Net reserves beginning of period 14,555,306 11,970,601 Incurred related to: Current year 3,302,013 2,835,129 Prior years ( 4,453) 2,727 Total incurred losses and LAE 3,297,560 2,837,856 Paid related to: Current year 710,677 570,460 Prior years 1,394,838 1,579,931 Total paid losses and LAE 2,105,515 2,150,391 Foreign exchange/translation adjustment 35,651 ( 74,372) Net reserves end of period 15,783,002 12,583,694 Plus reinsurance recoverables 1,862,760 1,692,947 Gross reserves end of period $ 17,645,762 $ 14,276,641 (Some amounts may not reconcile due to rounding.)

Fair Value (Tables)

Fair Value (Tables)	6 Months Ended
	Jun. 30, 2021
Fair Value [Abstract]
Fair Value Measurement Levels For All Assets And Liabilities	Fair Value Measurement Using: Quoted Prices in Active Significant Markets for Other Significant Identical Observable Unobservable Assets Inputs Inputs (Dollars in thousands) June 30, 2021 (Level 1) (Level 2) (Level 3) Assets: Fixed maturities, market value U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,275,758 $ - $ 1,275,758 $ - Obligations of U.S. States and political subdivisions 609,345 - 609,345 - Corporate securities 7,359,704 - 6,654,133 705,571 Asset-backed securities 3,169,417 - 2,354,141 815,276 Mortgage-backed securities Commercial 1,078,399 - 1,078,399 - Agency residential 2,290,267 - 2,290,267 - Non-agency residential 8,211 - 8,211 - Foreign government securities 1,553,961 - 1,553,961 - Foreign corporate securities 3,930,137 - 3,925,250 4,887 Total fixed maturities, market value 21,275,199 - 19,749,465 1,525,734 Equity securities, fair value 1,485,833 1,412,711 73,122 - Fair Value Measurement Using: Quoted Prices in Active Significant Markets for Other Significant Identical Observable Unobservable Assets Inputs Inputs (Dollars in thousands) December 31, 2020 (Level 1) (Level 2) (Level 3) Assets: Fixed maturities, market value U.S. Treasury securities and obligations of U.S. government agencies and corporations $ 1,367,106 $ - $ 1,367,106 $ - Obligations of U.S. States and political subdivisions 577,295 - 577,295 - Corporate securities 7,149,026 - 6,447,534 701,492 Asset-backed securities 2,565,802 - 1,942,769 623,033 Mortgage-backed securities Commercial 990,303 - 990,303 - Agency residential 2,267,739 - 2,267,739 - Non-agency residential 5,194 - 5,194 - Foreign government securities 1,645,375 - 1,645,375 - Foreign corporate securities 3,472,333 - 3,466,634 5,699 Total fixed maturities, market value 20,040,173 - 18,709,949 1,330,224 Equity securities, fair value 1,472,236 1,368,704 103,532 -
Activity Under Level 3, Fair Value Measurements Using Significant Unobservable Inputs By Asset Type	Total Fixed Maturities, Market Value Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 Corporate Asset-Backed Foreign Corporate Asset-Backed Foreign (Dollars in thousands) Securities Securities Corporate Total Securities Securities Corporate Total Beginning balance fixed maturities at market value $ 704,542 $ 785,360 $ 5,598 $ 1,495,500 $ 701,492 $ 623,033 $ 5,699 $ 1,330,224 Total gains or (losses) (realized/unrealized) Included in earnings ( 13,761) 206 137 ( 13,418) ( 15,550) ( 3,962) 140 ( 19,372) Included in other comprehensive income (loss) 4,582 7,610 ( 85) 12,107 7,418 4,475 ( 36) 11,857 Purchases, issuances and settlements 10,208 22,100 ( 763) 31,545 12,211 191,730 ( 916) 203,025 Transfers in and/or (out) of Level 3 - - - - - - - - Ending balance $ 705,571 $ 815,276 $ 4,887 $ 1,525,734 $ 705,571 $ 815,276 $ 4,887 $ 1,525,734 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date $ ( 17,279) $ ( 4,915) $ - $ ( 22,194) $ ( 17,279) $ ( 4,915) $ - $ ( 22,194) (Some amounts may not reconcile due to rounding.) Total Fixed Maturities, Market Value Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 Corporate Asset-Backed Foreign Corporate Asset-Backed Foreign (Dollars in thousands) Securities Securities Corporate Total Securities Securities Corporate Total Beginning balance fixed maturities at market value $ 713,081 $ 238,631 $ - $ 951,712 $ 617,588 $ 153,641 $ 1,750 $ 772,979 Total gains or (losses) (realized/unrealized) Included in earnings ( 248) 121 ( 97) ( 224) ( 462) 125 ( 97) ( 434) Included in other comprehensive income (loss) ( 549) 18,092 ( 40) 17,503 ( 3,906) 2,210 ( 40) ( 1,736) Purchases, issuances and settlements 14,345 38,886 5,434 58,665 113,409 139,754 3,684 256,847 Transfers in and/or (out) of Level 3 ( 4,795) - 977 ( 3,818) ( 4,795) - 977 ( 3,818) Ending balance $ 721,834 $ 295,730 $ 6,274 $ 1,023,838 $ 721,834 $ 295,730 $ 6,274 $ 1,023,838 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date $ - $ - $ - $ - $ ( 539) $ - $ - $ ( 539) (Some amounts may not reconcile due to rounding.) Total Fixed Maturities, Fair Value Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 Foreign Foreign (Dollars in thousands) Corporate Total Corporate Total Beginning balance fixed maturities at market value $ 4,703 $ 4,703 $ 5,826 $ 5,826 Total gains or (losses) (realized/unrealized) Included in earnings ( 272) ( 272) ( 1,395) ( 1,395) Included in other comprehensive income (loss) - - - - Purchases, issuances and settlements - - - - Transfers in and/or (out) of Level 3 - - - - Ending balance $ 4,431 $ 4,431 $ 4,431 $ 4,431 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date $ - $ - $ - $ - (Some amounts may not reconcile due to rounding.)
Fair Value Measurements Using Significant Unobservable Inputs For Equity Index Put Option Contracts	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Common Stock Balance, beginning of period $ - $ - $ - $ - Total (gains) or losses (realized/unrealized) Included in earnings - - - - Included in other comprehensive income (loss) - - - - Purchases, issuances and settlements - 9,877 - 9,877 Transfers in and/or (out) of Level 3 - - - - Balance, end of period $ - $ 9,877 $ - $ 9,877 The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to liabilities still held at the reporting date $ - $ - $ - $ - (Some amounts may not reconcile due to rounding.)

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2021
Earnings Per Common Share [Abstract]
Schedule Of Net Income (Loss) Per Common Share	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands, except per share amounts) 2021 2020 2021 2020 Net income (loss) per share: Numerator Net income (loss) $ 679,982 $ 190,880 $ 1,021,844 $ 207,492 Less: dividends declared-common shares and unvested common shares ( 62,045) ( 61,927) ( 124,274) ( 125,205) Undistributed earnings 617,937 128,953 897,570 82,287 Percentage allocated to common shareholders (1) 98.6 % 98.7 % 98.7 % 98.7 % 609,411 127,233 885,595 81,224 Add: dividends declared-common shareholders 61,245 61,148 122,659 123,637 Numerator for basic and diluted earnings per common share $ 670,656 $ 188,381 $ 1,008,254 $ 204,861 Denominator Denominator for basic earnings per weighted-average common shares 39,527 39,449 39,535 39,827 Effect of dilutive securities: Options 41 69 48 81 Denominator for diluted earnings per adjusted weighted-average common shares 39,567 39,519 39,582 39,908 Per common share net income (loss) Basic $ 16.97 $ 4.78 $ 25.50 $ 5.14 Diluted $ 16.95 $ 4.77 $ 25.47 $ 5.13 (1) Basic weighted-average common shares outstanding 39,527 39,449 39,535 39,827 Basic weighted-average common shares outstanding and unvested common shares expected to vest 40,080 39,983 40,069 40,348 Percentage allocated to common shareholders 98.6 % 98.7 % 98.7 % 98.7 % (Some amounts may not reconcile due to rounding.)

Commitments And Contingencies (

Commitments And Contingencies (Tables)	6 Months Ended
	Jun. 30, 2021
Commitments And Contingencies [Abstract]
Summary Of Estimated Cost To Replace Annuities For Contingent Liability	At June 30, At December 31, (Dollars in thousands) 2021 2020 The Prudential $ 139,236 $ 140,773 Unaffiliated life insurance company 33,492 35,128

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	6 Months Ended
	Jun. 30, 2021
Other Comprehensive Income (Loss) [Abstract]
Components Of Comprehensive Income (Loss) In The Consolidated Statements Of Operations	Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 (Dollars in thousands) Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized appreciation (depreciation) ("URA(D)") on securities - non-credit related $ 94,009 $ ( 9,838) $ 84,171 $ ( 235,157) $ 30,713 $ ( 204,444) Reclassification of net realized losses (gains) included in net income (loss) 3,118 ( 1,528) 1,590 ( 424) ( 1,652) ( 2,076) Foreign currency translation adjustments 38,022 ( 3,727) 34,295 29,034 ( 4,321) 24,713 Reclassification of benefit plan liability amortization included in net income (loss) 2,586 ( 543) 2,043 5,172 ( 1,086) 4,086 Total other comprehensive income (loss) $ 137,735 $ ( 15,636) $ 122,099 $ ( 201,375) $ 23,654 $ ( 177,721) Three Months Ended June 30, 2020 Six Months Ended June 30, 2020 (Dollars in thousands) Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized appreciation (depreciation) ("URA(D)") on securities - non-credit related $ 620,926 $ ( 69,173) $ 551,753 $ 305,725 $ ( 33,371) $ 272,354 Reclassification of net realized losses (gains) included in net income (loss) ( 6,849) ( 408) ( 7,257) 31,328 ( 7,186) 24,142 Foreign currency translation adjustments 22,825 ( 2,239) 20,586 ( 35,898) 5,660 ( 30,238) Reclassification of benefit plan liability amortization included in net income (loss) 2,286 ( 480) 1,806 3,451 ( 725) 2,726 Total other comprehensive income (loss) $ 639,188 $ ( 72,300) $ 566,888 $ 304,606 $ ( 35,622) $ 268,984
Reclassification From Accumulated Other Comprehensive Income	Three Months Ended Six Months Ended June 30, June 30, Affected line item within the statements of AOCI component 2021 2020 2021 2020 operations and comprehensive income (loss) (Dollars in thousands) URA(D) on securities $ 3,118 $ ( 6,849) $ ( 424) $ 31,328 Other net realized capital gains (losses) ( 1,528) ( 408) ( 1,652) ( 7,186) Income tax expense (benefit) $ 1,590 $ ( 7,257) $ ( 2,076) $ 24,142 Net income (loss) Benefit plan net gain (loss) $ 2,586 $ 2,286 $ 5,172 $ 3,451 Other underwriting expenses ( 543) ( 480) ( 1,086) ( 725) Income tax expense (benefit) $ 2,043 $ 1,806 $ 4,086 $ 2,726 Net income (loss)
Components Of Accumulated Other Comprehensive Income (Loss), Net Of Tax, In The Consolidated Balance Sheets	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Beginning balance of URA (D) on securities $ 431,878 $ 56,426 $ 724,159 $ 304,425 Current period change in URA (D) of investments - non-credit related 85,761 544,496 ( 206,520) 296,496 Ending balance of URA (D) on securities 517,639 600,922 517,639 600,922 Beginning balance of foreign currency translation adjustments ( 124,972) ( 252,541) ( 115,390) ( 201,717) Current period change in foreign currency translation adjustments 34,295 20,586 24,713 ( 30,238) Ending balance of foreign currency translation adjustments ( 90,677) ( 231,955) ( 90,677) ( 231,955) Beginning balance of benefit plan net gain (loss) ( 71,827) ( 73,636) ( 73,870) ( 74,556) Current period change in benefit plan net gain (loss) 2,043 1,806 4,086 2,726 Ending balance of benefit plan net gain (loss) ( 69,784) ( 71,830) ( 69,784) ( 71,830) Ending balance of accumulated other comprehensive income (loss) $ 357,178 $ 297,137 $ 357,178 $ 297,137 (Some amounts may not reconcile due to rounding.)

Credit Facilities (Tables)

Credit Facilities (Tables)	6 Months Ended
	Jun. 30, 2021
Line of Credit Facility [Line Items]
Summary Of Costs Incurred Connection With Credit Facilities	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Credit facility interest and fees incurred $ 70 $ 332 $ 175 $ 455 Loan interest and fees incurred - Federal Home Loan Bank 275 - 546 - Total interest and fees incurred $ 345 $ 332 $ 721 $ 455
Wells Fargo Bank Group Credit Facility [Member]
Line of Credit Facility [Line Items]
Summary Of Outstanding Letters Of Credit And Borrowings	(Dollars in thousands) At June 30, 2021 At December 31, 2020 Bank Commitment In Use Date of Expiry Commitment In Use Date of Expiry Wells Fargo Bank Group Credit Facility Tranche One $ - $ - $ 200,000 $ 164,242 12/31/2021 Tranche Two 600,000 402,284 12/31/2021 600,000 589,690 12/31/2021 Total Wells Fargo Bank Group Credit Facility $ 600,000 $ 402,284 $ 800,000 $ 753,932
Wells Fargo Bank Bilateral Loc Agreement [Member]
Line of Credit Facility [Line Items]
Summary Of Outstanding Letters Of Credit And Borrowings	(Dollars in thousands) At June 30, 2021 Bank Commitment In Use Date of Expiry Wells Fargo Bank Bilateral LOC Agreement $ 500,000 $ 404,421 12/31/2021 $ 500,000 $ 404,421
Citibank Bilateral Agreement [Member]
Line of Credit Facility [Line Items]
Summary Of Outstanding Letters Of Credit And Borrowings	(Dollars in thousands) At June 30, 2021 At December 31, 2020 Bank Commitment In Use Date of Expiry Commitment In Use Date of Expiry Citibank Bilateral Letter of Credit Agreement $ 200,000 $ 1,264 11/24/2021 $ 200,000 $ 4,425 02/28/2021 449 12/16/2021 3,672 11/24/2021 138,869 12/31/2021 448 12/16/2021 4,425 02/28/2022 115 12/20/2021 443 03/01/2022 136,383 12/31/2021 822 08/15/2022 39,619 12/30/2024 155 12/20/2022 821 08/15/2022 27,126 06/30/2025 - Total Citibank Bilateral Agreement $ 200,000 $ 173,553 $ 200,000 $ 185,483
Lloyds Bank plc Credit Facility [Member]
Line of Credit Facility [Line Items]
Summary Of Outstanding Letters Of Credit And Borrowings	(Dollars in thousands) At June 30, 2021 At December 31, 2020 Bank Commitment In Use Date of Expiry Commitment In Use Date of Expiry Lloyd's Bank plc £ 52,175 £ 52,175 12/31/2024 £ 52,175 £ 52,175 12/31/2023 - - - - Total Lloyd's Bank Credit Facility £ 52,175 £ 52,175 £ 52,175 £ 52,175

Collateralized Reinsurance An_2

Collateralized Reinsurance And Trust Agreements (Tables)	6 Months Ended
	Jun. 30, 2021
Collateralized Reinsurance And Trust Agreements [Abstract]
Premiums And Losses Ceded By The Company To Affiliate	Three Months Ended Six Months Ended June 30, June 30, Mt. Logan Re Segregated Accounts 2021 2020 2021 2020 (Dollars in thousands) Ceded written premiums $ 56,183 $ 48,522 $ 155,293 $ 158,710 Ceded earned premiums 71,422 71,143 149,529 161,693 Ceded losses and LAE 31,052 40,936 111,895 86,051 Assumed written premiums 2,741 2,795 5,217 5,554 Assumed earned premiums 2,741 2,795 5,217 5,554 Assumed losses and LAE - - - -
Summary of Collateralized Reinsurance Agreements	(Dollars in thousands) Class Description Effective Date Expiration Date Limit Series 2017-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/13/2017 4/13/2022 50,000 Series 2017-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/13/2017 4/13/2022 75,000 Series 2017-1 Class C-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/13/2017 4/13/2022 175,000 Series 2018-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/6/2022 62,500 Series 2018-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/6/2022 200,000 Series 2018-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/5/2023 62,500 Series 2018-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/30/2018 5/5/2023 200,000 Series 2019-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2023 150,000 Series 2019-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2023 275,000 Series 2019-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2024 150,000 Series 2019-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 12/12/2019 12/19/2024 275,000 Series 2020-1 Class A-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 150,000 Series 2020-1 Class B-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 85,000 Series 2020-1 Class C-1 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/21/2025 85,000 Series 2020-1 Class A-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 150,000 Series 2020-1 Class B-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 90,000 Series 2020-1 Class C-2 US, Canada, Puerto Rico – Named Storm and Earthquake Events 4/8/2021 4/20/2026 90,000 Total available limit as of June 30, 2021 $ 2,325,000
Schedule of Proceeds from Issuance of Notes Held in Reinsurance Trusts	(Dollars in thousands) Note Series Issue Date Maturity Date Amount Series 2017-1 Class A-2 4/13/2017 4/13/2022 50,000 Series 2017-1 Class B-2 4/13/2017 4/13/2022 75,000 Series 2017-1 Class C-2 4/13/2017 4/13/2022 175,000 Series 2018-1 Class A-1 4/30/2018 5/6/2022 62,500 Series 2018-1 Class B-1 4/30/2018 5/6/2022 200,000 Series 2018-1 Class A-2 4/30/2018 5/5/2023 62,500 Series 2018-1 Class B-2 4/30/2018 5/5/2023 200,000 Series 2019-1 Class A-1 12/12/2019 12/19/2023 150,000 Series 2019-1 Class B-1 12/12/2019 12/19/2023 275,000 Series 2019-1 Class A-2 12/12/2019 12/19/2024 150,000 Series 2019-1 Class B-2 12/12/2019 12/19/2024 275,000 Series 2020-1 Class A-1 4/8/2021 4/21/2025 150,000 Series 2020-1 Class B-1 4/8/2021 4/21/2025 85,000 Series 2020-1 Class C-1 4/8/2021 4/21/2025 85,000 Series 2020-1 Class A-2 4/8/2021 4/20/2026 150,000 Series 2020-1 Class B-2 4/8/2021 4/20/2026 90,000 Series 2020-1 Class C-2 4/8/2021 4/20/2026 90,000

Senior Notes (Tables)

Senior Notes (Tables)	6 Months Ended
	Jun. 30, 2021
Senior Notes [Abstract]
Schedule Of Outstanding Senior Notes	June 30, 2021 December 31, 2020 Consolidated Balance Consolidated Balance (Dollars in thousands) Date Issued Date Due Principal Amounts Sheet Amount Market Value Sheet Amount Market Value 4.868% Senior notes 6/5/2014 6/1/2044 400,000 $ 397,254 $ 505,284 $ 397,194 $ 528,000 3.5% Senior notes 10/07/2020 10/15/2050 1,000,000 979,784 1,068,990 979,524 1,138,100
Schedule Of Interest Expense Incurred In Connection With Senior Notes	Three Months Ended Six Months Ended June 30, June 30, (Dollars In thousands 2021 2020 2021 2020 Interest expense incurred 4.868% Senior notes $ 4,868 $ 4,868 $ 9,736 $ 9,736 Interest expense incurred 3.5% Senior notes 8,805 - 17,610 -

Long Term Subordinated Notes (T

Long Term Subordinated Notes (Tables)	6 Months Ended
	Jun. 30, 2021
Long Term Subordinated Notes [Abstract]
Schedule Of Outstanding Fixed To Floating Rate Long Term Subordinated Notes	Maturity Date June 30, 2021 December 31, 2020 Original Consolidated Balance Market Consolidated Balance Market (Dollars in thousands) Date Issued Principal Amount Scheduled Final Sheet Amount Value Sheet Amount Value Long term subordinated notes 4/26/2007 $ 400,000 5/15/2037 5/1/2067 $ 223,724 $ 214,772 $ 223,674 $ 206,447
Schedule Of Interest Expense Incurred In Connection With Long Term Subordinated Notes	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Interest expense incurred $ 1,460 $ 2,000 $ 2,922 $ 4,539

Segment Reporting (Tables)

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Schedule Of Underwriting Results For Operating Segments	Three Months Ended Six Months Ended Reinsurance June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Gross written premiums $ 2,148,235 $ 1,538,348 $ 4,207,250 $ 3,316,119 Net written premiums 2,059,919 1,424,089 3,972,868 3,037,183 Premiums earned $ 1,920,801 $ 1,502,256 $ 3,698,253 $ 2,987,476 Incurred losses and LAE 1,168,139 1,005,677 2,440,045 2,026,319 Commission and brokerage 473,258 387,339 881,982 757,695 Other underwriting expenses 47,065 39,698 99,061 83,837 Underwriting gain (loss) $ 232,339 $ 69,542 $ 277,165 $ 119,625 Three Months Ended Six Months Ended Insurance June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Gross written premiums $ 1,041,905 $ 830,990 $ 1,914,323 $ 1,624,090 Net written premiums 749,492 593,389 1,390,479 1,181,774 Premiums earned $ 637,571 $ 540,149 $ 1,247,984 $ 1,091,743 Incurred losses and LAE 418,002 401,339 857,515 811,537 Commission and brokerage 84,490 78,977 164,777 157,143 Other underwriting expenses 93,779 78,432 184,014 163,153 Underwriting gain (loss) $ 41,300 $ ( 18,599) $ 41,678 $ ( 40,090)
Schedule Of Underwriting Results For Operating Segments To Income (Loss) Before Taxes	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Underwriting gain (loss) $ 273,639 $ 50,943 $ 318,843 $ 79,535 Net investment income 407,095 38,083 667,508 185,883 Net realized capital gains (losses) 104,109 184,648 143,011 ( 25,940) Corporate expenses ( 16,168) ( 8,733) ( 28,546) ( 18,566) Interest, fee and bond issue cost amortization expense ( 15,607) ( 7,253) ( 31,246) ( 14,836) Other income (expense) 7,114 ( 20,621) 63,707 ( 12,631) Income (loss) before taxes $ 760,181 $ 237,067 $ 1,133,276 $ 193,445
Schedule Of Gross Written Premiums Derived From Largest Non-U.S. Market	Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 United Kingdom gross written premium $ 249,314 $ 236,100 $ 615,462 $ 542,808

Retirement Benefits (Tables)

Retirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2021
Defined Benefit Pension Plan [Member]
Net Periodic Benefit Cost For U.S. Employees	Pension Benefits Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Service cost $ 2,738 $ 2,041 $ 5,476 $ 6,052 Interest cost 1,999 2,563 3,998 5,046 Expected return on plan assets ( 5,580) ( 5,197) ( 11,161) ( 10,394) Amortization of net (income) loss 2,731 2,462 5,461 3,675 Net periodic benefit cost $ 1,888 $ 1,869 $ 3,774 $ 4,379
Post-Retirement Plan [Member]
Net Periodic Benefit Cost For U.S. Employees	Other Benefits Three Months Ended Six Months Ended June 30, June 30, (Dollars in thousands) 2021 2020 2021 2020 Service cost $ 281 $ 311 $ 564 $ 452 Interest cost 181 215 362 429 Amortization of prior service cost ( 144) ( 176) ( 289) ( 224) Net periodic benefit cost $ 318 $ 350 $ 637 $ 657

Basis Of Presentation (Narrativ

Basis Of Presentation (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Basis Of Accounting [Line Items]
Total shareholders' equity	$ 10,416,789		$ 9,726,176	$ 9,286,299
Retained Earnings [Member]
Basis Of Accounting [Line Items]
Total shareholders' equity	$ 11,465,022	$ 10,847,086	10,567,452	$ 10,384,645	$ 10,255,692	$ 10,306,571
Retained Earnings [Member] | Cumulative Effect Period Of Adoption Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Basis Of Accounting [Line Items]
Total shareholders' equity						$ (4,214)

Investments (Narrative) (Detail

Investments (Narrative) (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Additional contractual commitments	$ 2,866,741,000
Contractual commitments, investment period expiration date	Dec. 31, 2026
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Aggregate market value of investments in unrealized loss position	$ 5,115,149,000	$ 2,678,449,000
Gross unrealized losses on investments in unrealized loss position	154,529,000	124,812,000
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation	147,673,000	67,958,000
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	6,856,000	56,854,000
Market value of investments	$ 21,275,199,000	$ 20,040,173,000
Fixed Maturity Securities [Member] | Sales Revenue, Net [Member] | Issuer with the second the largest unrealized loss position [Member] | Issuer [Member]
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold of unrealized losses not exceeded by any one single issuer	0.30%	0.10%
Fixed Maturity Securities [Member] | US Government Securities [Member] | Sales Revenue, Net [Member] | Issuer [Member]
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold of unrealized losses not exceeded by any one single issuer	1.60%	0.70%
Investment Grade [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation	$ 133,996,000	$ 63,424,000
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation	6,678,000	33,533,000
Sub-prime and Alt-A Loans [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross unrealized depreciation	0	$ 0
Private Placement Liquidity Sweep [Member]
Schedule of Available-for-sale Securities [Line Items]
Market value of investments	$ 575,807,000

Investments (Summary Of Unreali

Investments (Summary Of Unrealized Appreciation (Depreciation) Of Available For Sale, Fixed Maturity And Equity Security Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 20,718,717
Allowance for credit losses	(24,650)	$ (8,723)	$ (1,745)	$ (25,837)	$ (21,774)
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,718,717		19,225,067
Allowance for credit losses	(24,650)		(1,745)
Unrealized Appreciation	735,661		941,663
Unrealized Depreciation	(154,529)		(124,812)
Market Value	21,275,199		20,040,173
U.S. Treasury Securities And Obligations Of U.S. Government Agencies And Corporations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,259,149		1,325,156
Allowance for credit losses
Unrealized Appreciation	29,365		49,084
Unrealized Depreciation	(12,756)		(7,134)
Market Value	1,275,758		1,367,106
Obligations Of U.S. States And Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	574,398		543,895
Allowance for credit losses
Unrealized Appreciation	35,933		34,654
Unrealized Depreciation	(986)		(1,254)
Market Value	609,345		577,295
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,155,688		6,824,800
Allowance for credit losses	(18,475)	(3,603)	(1,220)	(22,253)	(17,305)
Unrealized Appreciation	285,509		380,677
Unrealized Depreciation	(63,018)		(55,231)
Market Value	7,359,704		7,149,026
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,141,971		2,540,809
Allowance for credit losses	(4,915)	(4,915)
Unrealized Appreciation	35,316		30,691
Unrealized Depreciation	(2,955)		(5,698)
Market Value	3,169,417		2,565,802
Mortgage-Backed Securities: Commercial [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,026,809		915,923
Allowance for credit losses
Unrealized Appreciation	55,125		75,275
Unrealized Depreciation	(3,535)		(895)
Market Value	1,078,399		990,303
Mortgage Backed Securities: Agency residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,255,348		2,206,139
Allowance for credit losses
Unrealized Appreciation	47,124		64,663
Unrealized Depreciation	(12,205)		(3,063)
Market Value	2,290,267		2,267,739
Mortgage Backed Securities: Non-agency residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,220		5,187
Allowance for credit losses
Unrealized Appreciation	6		9
Unrealized Depreciation	(15)		(2)
Market Value	8,211		5,194
Foreign Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,494,989		1,565,260
Allowance for credit losses			(22)	(92)	(519)
Unrealized Appreciation	80,268		102,587
Unrealized Depreciation	(21,296)		(22,450)
Market Value	1,553,961		1,645,375
Foreign Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,802,145		3,297,898
Allowance for credit losses	(1,260)	$ (205)	(503)	$ (3,492)	$ (3,950)
Unrealized Appreciation	167,015		204,023
Unrealized Depreciation	(37,763)		(29,085)
Market Value	$ 3,930,137		$ 3,472,333

Investments (Summary Of Amortiz

Investments (Summary Of Amortized Cost And Market Value Of Fixed Maturity Securities, By Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities - available for sale, Amortized Cost	$ 20,718,717	$ 19,225,067
Fixed maturity securities - available for sale, Market Value	21,275,199	20,040,173
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities - available for sale, Due in one year or less, Amortized Cost	1,628,113	1,365,793
Fixed maturity securities - available for sale, Due after one year through five years, Amortized Cost	6,432,847	6,529,189
Fixed maturity securities - available for sale, Due after five years through ten years, Amortized Cost	4,890,259	4,414,211
Fixed maturity securities - available for sale, Due after ten years, Amortized Cost	1,335,150	1,247,816
Fixed maturity securities - available for sale, Due in one year or less, Market Value	1,638,768	1,374,674
Fixed maturity securities - available for sale, Due after one year through five years, Market Value	6,618,429	6,774,785
Fixed maturity securities - available for sale, Due after five years through ten years, Market Value	5,091,435	4,751,903
Fixed maturity securities - available for sale, Due after ten years, Market Value	1,380,273	1,309,773
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities - available for sale, Amortized Cost	3,141,971	2,540,809
Fixed maturity securities - available for sale, Market Value	3,169,417	2,565,802
Mortgage-Backed Securities: Commercial [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities - available for sale, Amortized Cost	1,026,809	915,923
Fixed maturity securities - available for sale, Market Value	1,078,399	990,303
Mortgage Backed Securities: Agency residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities - available for sale, Amortized Cost	2,255,348	2,206,139
Fixed maturity securities - available for sale, Market Value	2,290,267	2,267,739
Mortgage Backed Securities: Non-agency residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities - available for sale, Amortized Cost	8,220	5,187
Fixed maturity securities - available for sale, Market Value	$ 8,211	$ 5,194

Investments (Summary Of Changes

Investments (Summary Of Changes In Net Unrealized Appreciation (Depreciation) For The Company's Investments) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Schedule of Available-for-sale Securities [Line Items]
Change in unrealized appreciation (depreciation), pre-tax	$ 97,127	$ 614,077	$ (235,581)	$ 337,053
Deferred tax benefit (expense)	(11,366)	(69,581)	29,061	(40,557)
Total URA(D) on securities arising during the period	85,761	544,496	(206,520)	296,496
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Change in unrealized appreciation (depreciation), pre-tax	$ 97,127	$ 614,077	$ (235,581)	$ 337,053

Investments (Summary Of Aggrega

Investments (Summary Of Aggregate Market Value And Gross Unrealized Depreciation Of Fixed Maturity And Equity Securities, By Security Type) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	$ 4,997,468	$ 2,017,481
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(147,673)	(67,958)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	117,681	660,968
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(6,856)	(56,854)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	5,115,149	2,678,449
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(154,529)	(124,812)
U.S. Treasury Securities And Obligations Of U.S. Government Agencies And Corporations [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	341,846	135,190
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(12,494)	(7,134)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	2,620
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(262)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	344,466	135,190
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(12,756)	(7,134)
Obligations Of U.S. States And Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	23,662	19,524
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(986)	(999)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value		4,059
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation		(255)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	23,662	23,583
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(986)	(1,254)
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	1,598,159	669,755
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(61,141)	(26,159)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	37,936	247,962
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(1,877)	(29,072)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	1,636,095	917,717
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(63,018)	(55,231)
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	710,904	235,566
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(2,955)	(4,768)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value		85,595
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation		(930)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	710,904	321,161
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(2,955)	(5,698)
Mortgage-Backed Securities: Commercial [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	134,941	53,511
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(3,535)	(578)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value		6,592
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation		(317)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	134,941	60,103
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(3,535)	(895)
Mortgage Backed Securities: Agency residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	1,020,232	434,447
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(11,327)	(2,016)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	43,983	50,353
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(878)	(1,047)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	1,064,215	484,800
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(12,205)	(3,063)
Mortgage Backed Securities: Non-agency residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	1,309	185
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(15)	(2)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	1,309	185
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(15)	(2)
Foreign Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	304,722	114,755
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(20,686)	(8,813)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	3,107	150,812
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(610)	(13,637)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	307,829	265,567
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(21,296)	(22,450)
Foreign Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	861,693	354,548
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(34,534)	(17,489)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	30,035	115,595
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(3,229)	(11,596)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	891,728	470,143
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	$ (37,763)	$ (29,085)

Investments (Summary Of Aggre_2

Investments (Summary Of Aggregate Market Value And Gross Unrealized Depreciation Of Fixed Maturity And Equity Securities, By Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	$ 4,997,468	$ 2,017,481
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(147,673)	(67,958)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	117,681	660,968
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(6,856)	(56,854)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	5,115,149	2,678,449
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(154,529)	(124,812)
Due In One Year Or Less [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	260,687	96,144
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(15,951)	(4,942)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	5,846	112,419
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(471)	(12,071)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	266,533	208,563
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(16,422)	(17,013)
Due In One Year Through Five Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	1,385,520	653,816
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(51,928)	(32,469)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	48,824	283,866
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(3,048)	(21,319)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	1,434,344	937,682
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(54,976)	(53,788)
Due In Five Years Through Ten Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	1,153,553	422,517
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(48,557)	(19,392)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	19,028	49,749
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(2,459)	(2,034)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	1,172,581	472,266
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(51,016)	(21,426)
Due After Ten Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	330,322	121,295
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(13,405)	(3,791)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value		72,394
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation		(19,136)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	330,322	193,689
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(13,405)	(22,927)
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	710,904	235,566
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(2,955)	(4,768)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value		85,595
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation		(930)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	710,904	321,161
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	(2,955)	(5,698)
Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Market Value	1,156,482	488,143
Fixed maturity securities, Duration of Unrealized Loss, Less than 12 months, Gross Unrealized Depreciation	(14,877)	(2,596)
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Market Value	43,983	56,945
Fixed maturity securities, Duration of Unrealized Loss, Greater than 12 months, Gross Unrealized Depreciation	(878)	(1,364)
Fixed maturity securities, Duration of Unrealized Loss, Total, Market Value	1,200,465	545,088
Fixed maturity securities, Duration of Unrealized Loss, Total, Gross Unrealized Depreciation, Total	$ (15,755)	$ (3,960)

Investments (Summary Of Compone

Investments (Summary Of Components Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	$ 418,349	$ 48,051	$ 684,635	$ 200,168
Funds held interest income (expense)	3,287	2,021	11,253	10,237
Future policy benefit reserve income (expense)	(170)	(303)	(461)	(514)
Gross investment income	421,466	49,769	695,427	209,891
Investment expenses	(14,371)	(11,686)	(27,919)	(24,008)
Net investment income	407,095	38,083	667,508	185,883
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	148,262	133,918	289,178	271,842
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	3,493	3,662	8,331	7,183
Short Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	773	1,687	953	3,862
Limited Partnerships [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	239,966	(88,254)	354,299	(66,686)
Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	$ 25,855	$ (2,962)	$ 31,874	$ (16,033)

Investments (Summary Of Compo_2

Investments (Summary Of Components Of Net Realized Capital Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Schedule of Available-for-sale Securities [Line Items]
Total net realized capital gains (losses)	$ 104,109	$ 184,648	$ 143,011	$ (25,940)
Beginning Balance	(8,723)	(21,774)	(1,745)
Credit losses on securities where credit losses were not previously recorded	(14,592)	(10,960)	(21,890)	(32,734)
Increases in allowance on previously impaired securities	(1,468)	(1,082)	(1,468)	(1,082)
Decrease in allowance on previously impaired securities		4,336		4,336
Reduction in allowance due to disposals	133	3,643	453	3,643
Ending Balance	(24,650)	(25,837)	(24,650)	(25,837)
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Beginning Balance			(1,745)
Ending Balance	(24,650)		(24,650)
Fixed Maturity Securities [Member] | Market Value [Member]
Schedule of Available-for-sale Securities [Line Items]
Allowance for credit losses	(15,927)	(4,063)	(22,904)	(25,837)
Gains (losses) from sales	10,060	9,619	19,234	(4,457)
Fixed Maturity Securities [Member] | Fair Value [Member]
Schedule of Available-for-sale Securities [Line Items]
Gains (losses) from sales
Gains (losses) from fair value adjustments		(272)		(1,395)
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Beginning Balance	(3,603)	(17,305)	(1,220)
Credit losses on securities where credit losses were not previously recorded	(13,537)	(10,355)	(15,920)	(27,660)
Increases in allowance on previously impaired securities	(1,468)	(782)	(1,468)	(782)
Decrease in allowance on previously impaired securities		3,431		3,431
Reduction in allowance due to disposals	133	2,758	133	2,758
Ending Balance	(18,475)	(22,253)	(18,475)	(22,253)
Equity Securities [Member] | Fair Value [Member]
Schedule of Available-for-sale Securities [Line Items]
Gains (losses) from sales	3,755	16,274	9,993	(11,325)
Gains (losses) from fair value adjustments	103,525	161,694	132,581	17,691
Other Invested Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Gains (losses) from sales	2,748	1,293	4,094	(1,034)
Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Gains (losses) from sales	(52)	103	13	417
Asset Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Beginning Balance	(4,915)
Credit losses on securities where credit losses were not previously recorded			(4,915)
Increases in allowance on previously impaired securities
Decrease in allowance on previously impaired securities
Reduction in allowance due to disposals
Ending Balance	(4,915)		(4,915)
Foreign Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Beginning Balance		(519)	(22)
Credit losses on securities where credit losses were not previously recorded				(519)
Increases in allowance on previously impaired securities
Decrease in allowance on previously impaired securities		212		212
Reduction in allowance due to disposals		215	22	215
Ending Balance		(92)		(92)
Foreign Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Beginning Balance	(205)	(3,950)	(503)
Credit losses on securities where credit losses were not previously recorded	(1,055)	(605)	(1,055)	(4,555)
Increases in allowance on previously impaired securities		(300)		(300)
Decrease in allowance on previously impaired securities		693		693
Reduction in allowance due to disposals		670	298	670
Ending Balance	$ (1,260)	$ (3,492)	$ (1,260)	$ (3,492)

Investments (Summary Of Gross G

Investments (Summary Of Gross Gains (Losses) From Sales Of Fixed Maturity And Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities	$ 371,459	$ 488,320	$ 599,737	$ 990,273
Gross gains from sales	19,870	21,355	34,734	35,356
Gross losses from sales	(9,810)	(11,736)	(15,500)	(39,813)
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities	193,350	100,344	474,663	213,185
Gross gains from sales	5,803	18,172	18,107	20,756
Gross losses from sales	$ (2,048)	$ (1,898)	$ (8,114)	$ (32,081)

Reserve For Losses, LAE And F_3

Reserve For Losses, LAE And Future Policy Benefit Reserve (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Reserve For Losses LAE And Future Policy Benefit Reserve [Line Items]
Current year losses		$ 3,302,013	$ 2,835,129
Catastrophe Losses [Member]
Reserve For Losses LAE And Future Policy Benefit Reserve [Line Items]
Current year losses		$ 270,000
Covid-19 [Member]
Reserve For Losses LAE And Future Policy Benefit Reserve [Line Items]
Current year losses	$ 159,978		$ 309,978

Reserve For Losses, LAE And F_4

Reserve For Losses, LAE And Future Policy Benefit Reserve (Summary Of Activity In The Reserve For Losses And LAE) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Reserve For Losses, LAE And Future Policy Benefit Reserve [Abstract]
Gross reserves beginning of period	$ 16,398,997	$ 13,611,313
Less reinsurance recoverables	(1,843,691)	(1,640,712)
Net reserves beginning of period	14,555,306	11,970,601
Incurred related to: Current year	3,302,013	2,835,129
Incurred related to: Prior years	(4,453)	2,727
Total incurred losses and LAE	3,297,560	2,837,856
Paid related to: Current year	710,677	570,460
Paid related to: Prior years	1,394,838	1,579,931
Total paid losses and LAE	2,105,515	2,150,391
Foreign exchange/translation adjustment	35,651	(74,372)
Net reserves end of period	15,783,002	12,583,694
Plus reinsurance recoverables	1,862,760	1,692,947
Gross reserves end of period	$ 17,645,762	$ 14,276,641

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of public equity portfolio	$ 1,116,408	$ 784,746
Other invested assets	868,477	742,369
Fair Value [Member] | Investments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other invested assets	289,278	224,698
Fixed Maturities [Member] | Market Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale Securities	$ 1,525,734	$ 1,330,224

Fair Value (Fair Value Measurem

Fair Value (Fair Value Measurement Levels For All Assets And Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	$ 21,275,199	$ 20,040,173
Equity securities, fair value	1,485,833	1,472,236
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, fair value	1,412,711	1,368,704
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, fair value	73,122	103,532
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, fair value
Fixed Maturity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	21,275,199	20,040,173
Fixed Maturity Securities [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Fixed Maturity Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	19,749,465	18,709,949
Fixed Maturity Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	1,525,734	1,330,224
U.S. Treasury Securities And Obligations Of U.S. Government Agencies And Corporations [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	1,275,758	1,367,106
U.S. Treasury Securities And Obligations Of U.S. Government Agencies And Corporations [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
U.S. Treasury Securities And Obligations Of U.S. Government Agencies And Corporations [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	1,275,758	1,367,106
U.S. Treasury Securities And Obligations Of U.S. Government Agencies And Corporations [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Obligations Of U.S. States And Political Subdivisions [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	609,345	577,295
Obligations Of U.S. States And Political Subdivisions [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Obligations Of U.S. States And Political Subdivisions [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	609,345	577,295
Obligations Of U.S. States And Political Subdivisions [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	7,359,704	7,149,026
Corporate Securities [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Corporate Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	6,654,133	6,447,534
Corporate Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	705,571	701,492
Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	3,169,417	2,565,802
Asset-Backed Securities [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Asset-Backed Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	2,354,141	1,942,769
Asset-Backed Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	815,276	623,033
Mortgage-Backed Securities: Commercial [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	1,078,399	990,303
Mortgage-Backed Securities: Commercial [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Mortgage-Backed Securities: Commercial [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	1,078,399	990,303
Mortgage-Backed Securities: Commercial [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Mortgage Backed Securities: Agency residential [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	2,290,267	2,267,739
Mortgage Backed Securities: Agency residential [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Mortgage Backed Securities: Agency residential [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	2,290,267	2,267,739
Mortgage Backed Securities: Agency residential [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Mortgage Backed Securities: Non-agency residential [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	8,211	5,194
Mortgage Backed Securities: Non-agency residential [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Mortgage Backed Securities: Non-agency residential [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	8,211	5,194
Mortgage Backed Securities: Non-agency residential [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Foreign Government Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	1,553,961	1,645,375
Foreign Government Securities [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Foreign Government Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	1,553,961	1,645,375
Foreign Government Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Foreign Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	3,930,137	3,472,333
Foreign Corporate Securities [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value
Foreign Corporate Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	3,925,250	3,466,634
Foreign Corporate Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturities - available for sale, at market value	$ 4,887	$ 5,699

Fair Value (Activity Under Leve

Fair Value (Activity Under Level 3, Fair Value Measurements Using Significant Unobservable Inputs By Asset Type) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Market Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities	$ 1,495,500	$ 951,712	$ 1,330,224	$ 772,979
Total gains or (losses) (realized/unrealized) Included in earnings	(13,418)	(224)	(19,372)	(434)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)	12,107	17,503	11,857	(1,736)
Purchases, issuances and settlements	31,545	58,665	203,025	256,847
Transfer in and/or (out) of Level 3		(3,818)		(3,818)
Ending balance	1,525,734	1,023,838	1,525,734	1,023,838
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	(22,194)		(22,194)	(539)
Market Value [Member] | Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities	704,542	713,081	701,492	617,588
Total gains or (losses) (realized/unrealized) Included in earnings	(13,761)	(248)	(15,550)	(462)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)	4,582	(549)	7,418	(3,906)
Purchases, issuances and settlements	10,208	14,345	12,211	113,409
Transfer in and/or (out) of Level 3		(4,795)		(4,795)
Ending balance	705,571	721,834	705,571	721,834
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	(17,279)		(17,279)	(539)
Market Value [Member] | Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities	785,360	238,631	623,033	153,641
Total gains or (losses) (realized/unrealized) Included in earnings	206	121	(3,962)	125
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)	7,610	18,092	4,475	2,210
Purchases, issuances and settlements	22,100	38,886	191,730	139,754
Transfer in and/or (out) of Level 3
Ending balance	815,276	295,730	815,276	295,730
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	(4,915)		(4,915)
Market Value [Member] | Foreign Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities	5,598		5,699	1,750
Total gains or (losses) (realized/unrealized) Included in earnings	137	(97)	140	(97)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)	(85)	(40)	(36)	(40)
Purchases, issuances and settlements	(763)	5,434	(916)	3,684
Transfer in and/or (out) of Level 3		977		977
Ending balance	4,887	6,274	4,887	6,274
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date
Fair Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities		4,703		5,826
Total gains or (losses) (realized/unrealized) Included in earnings		(272)		(1,395)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)
Purchases, issuances and settlements
Transfer in and/or (out) of Level 3
Ending balance		4,431		4,431
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date
Fair Value [Member] | Foreign Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities		4,703		5,826
Total gains or (losses) (realized/unrealized) Included in earnings		(272)		(1,395)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)
Purchases, issuances and settlements
Transfer in and/or (out) of Level 3
Ending balance		4,431		4,431
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date

Fair Value (Fair Value Measur_2

Fair Value (Fair Value Measurements Using Significant Unobservable Inputs For Equity Index Put Option Contracts) (Details) - Common Stock [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance, beginning of period
Total (gains) or losses (realized/unrealized) Included in earnings
Total (gains) or losses (realized/unrealized) Included in other comprehensive income (loss)
Purchases, issuances and settlements		9,877		9,877
Transfers in and/or (out) of Level 3
Balance, end of period		9,877		9,877
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to liabilities still held at the reporting date

Earnings Per Common Share (Narr

Earnings Per Common Share (Narrative) (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive options	0	0	0	0
Minimum [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Options expiration date			Feb. 22, 2022
Maximum [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Options expiration date			Sep. 19, 2022

Earnings Per Common Share (Sche

Earnings Per Common Share (Schedule Of Net Income (Loss) Per Common Share) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Common Share [Abstract]
Net income (loss)	$ 679,982,000	$ 190,880,000	$ 1,021,844,000	$ 207,492,000
Less: dividends declared-common shares and nonvested common shares	(62,045,000)	(61,927,000)	(124,274,000)	(125,205,000)
Undistributed earnings	$ 617,937,000	$ 128,953,000	$ 897,570,000	$ 82,287,000
Percentage allocated to common shareholders	98.60%	98.70%	98.70%	98.70%
Net income (loss) available to common stockholders, total	$ 609,411,000	$ 127,233,000	$ 885,595,000	$ 81,224,000
Add: dividends declared-common shareholders	61,245,000	61,148,000	122,659,000	123,637,000
Numerator for basic and diluted earnings per common share	$ 670,656,000	$ 188,381,000	$ 1,008,254,000	$ 204,861,000
Denominator for basic earnings per weighted-average common shares	39,527,000	39,449,000	39,535,000	39,827,000
Effect of dilutive securities: Options	41,000	69,000	48,000	81,000
Denominator for diluted earnings per adjusted weighted-average common shares	39,567,000	39,519,000	39,582,000	39,908,000
Per common share net income (loss)
Basic	$ 16.97	$ 4.78	$ 25.50	$ 5.14
Diluted	$ 16.95	$ 4.77	$ 25.47	$ 5.13
Basic weighted-average common shares outstanding	39,527,000	39,449,000	39,535,000	39,827,000
Basic weighted-average common shares outstanding and nonvested common shares expected to vest	40,080,000	39,983,000	40,069,000	40,348,000

Commitments And Contingencies_2

Commitments And Contingencies (Narrative) (Details) - Equity Index Put Option [Member] - Standard & Poor's 500 [Member]	6 Months Ended
	Jun. 30, 2021USD ($)Item$ / Item
Derivative [Line Items]
Number of equity index put option contracts | Item	1
Probability of falling below strike price, percentage	0.10%
Index | $ / Item	4,297.50
Theoretical [Member]
Derivative [Line Items]
Maximum discount factor	3.00%
Maximum payout occurs based on index value	$ 150,077,000
If Contracts Expire [Member]
Derivative [Line Items]
Settlement amount	$ 0

Commitments And Contingencies_3

Commitments And Contingencies (Summary Of Estimated Cost To Replace Annuities For Contingent Liability) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
The Prudential [Member]
Loss Contingencies [Line Items]
Estimated cost to replace annuities	$ 139,236	$ 140,773
Unaffiliated Life Insurance Company [Member]
Loss Contingencies [Line Items]
Estimated cost to replace annuities	$ 33,492	$ 35,128

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Components Of Comprehensive Income (Loss) In The Consolidated Statements Of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total, Before Tax	$ 137,735	$ 639,188	$ (201,375)	$ 304,606
Total, Tax Effect	(15,636)	(72,300)	23,654	(35,622)
Total, Net of Tax	122,099	566,888	(177,721)	268,984
URA(D) On Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Before Tax	94,009	620,926	(235,157)	305,725
Tax Effect	(9,838)	(69,173)	30,713	(33,371)
Net of Tax	84,171	551,753	(204,444)	272,354
Reclassification, Before Tax	3,118	(6,849)	(424)	31,328
Reclassification, Tax Effect	(1,528)	(408)	(1,652)	(7,186)
Reclassification, Net of Tax	1,590	(7,257)	(2,076)	24,142
Total, Net of Tax	85,761	544,496	(206,520)	296,496
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Before Tax	38,022	22,825	29,034	(35,898)
Tax Effect	(3,727)	(2,239)	(4,321)	5,660
Net of Tax	34,295	20,586	24,713	(30,238)
Total, Net of Tax	34,295	20,586	24,713	(30,238)
Benefit Plan Net Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification, Before Tax	2,586	2,286	5,172	3,451
Reclassification, Tax Effect	(543)	(480)	(1,086)	(725)
Reclassification, Net of Tax	2,043	1,806	4,086	2,726
Total, Net of Tax	$ 2,043	$ 1,806	$ 4,086	$ 2,726

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) (Reclassification From Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense (benefit)	$ (80,199)	$ (46,187)	$ (111,432)	$ 14,047
NET INCOME (LOSS)	679,982	190,880	1,021,844	207,492
URA(D) On Securities [Member] | Reclassification From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other net realized capital gains (losses)	3,118	(6,849)	(424)	31,328
Income tax expense (benefit)	(1,528)	(408)	(1,652)	(7,186)
NET INCOME (LOSS)	1,590	(7,257)	(2,076)	24,142
Benefit Plan Net Gain (Loss) [Member] | Reclassification From Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other underwriting expenses	2,586	2,286	5,172	3,451
Income tax expense (benefit)	(543)	(480)	(1,086)	(725)
NET INCOME (LOSS)	$ 2,043	$ 1,806	$ 4,086	$ 2,726

Other Comprehensive Income (L_5

Other Comprehensive Income (Loss) (Components Of Accumulated Other Comprehensive Income (Loss), Net Of Tax, In The Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance		$ 9,726,176			$ 9,726,176
Current period change	$ 122,099		$ 566,888		(177,721)	$ 268,984
Balance	10,416,789		9,286,299		10,416,789	9,286,299
URA(D) On Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	431,878	724,159	56,426	$ 304,425	724,159	304,425
Current period change	85,761		544,496		(206,520)	296,496
Balance	517,639	431,878	600,922	56,426	517,639	600,922
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(124,972)	(115,390)	(252,541)	(201,717)	(115,390)	(201,717)
Current period change	34,295		20,586		24,713	(30,238)
Balance	(90,677)	(124,972)	(231,955)	(252,541)	(90,677)	(231,955)
Benefit Plan Net Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(71,827)	(73,870)	(73,636)	(74,556)	(73,870)	(74,556)
Current period change	2,043		1,806		4,086	2,726
Balance	(69,784)	(71,827)	(71,830)	(73,636)	(69,784)	(71,830)
Accumulated Other Comprehensive Income (Loss), Net of Deferred Income Taxes [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	235,079	534,899	(269,751)	28,152	534,899	28,152
Current period change	122,099	(299,820)	566,888	(297,903)
Balance	$ 357,178	$ 235,079	$ 297,137	$ (269,751)	$ 357,178	$ 297,137

Credit Facilities (Narrative) (

Credit Facilities (Narrative) (Details)	May 26, 2016USD ($)	Jun. 22, 2012USD ($)	Jun. 30, 2021GBP (£)ItemRate	Jun. 30, 2021GBP (£)ItemRate	Dec. 31, 2020GBP (£)	Dec. 31, 2019	Jun. 30, 2021USD ($)ItemRate	May 05, 2021USD ($)	Feb. 23, 2021USD ($)	Dec. 31, 2020USD ($)	Mar. 25, 2020USD ($)
Line of Credit Facility [Line Items]
Line of credit facility, commitment							$ 1,300,000,000
Maximum percentage of admitted assets allowed for borrowing base			10.00%	10.00%			10.00%
Borrowings from FHLB							$ 310,000,000			$ 310,000,000
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Percentage commitment fee per annum				0.10%
Per annum commitment fee on undrawn credit				0.35%
Active Credit Facilities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, number of facilities			3	3			3
Wells Fargo Bank Group Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit facility, term of credit facility	5 years	4 years
Line of credit facility, commitment	$ 800,000,000	$ 800,000,000					$ 600,000,000			800,000,000
Line of credit facility, number of tranches | Item			2	2			2
Line of credit facility, required debt-to-capital ratio | Rate			35.00%	35.00%			35.00%
Line of credit facility, required minimum net worth							$ 5,370,979,000
Percentage amount of consolidated net income required to be reserved to maintain compliance with facility covenants				25.00%
Percentage amount of increase in consolidated net worth from new issuance required to be reserved to maintain compliance with facility covenants				25.00%
Increase in reserves due to new issuance during the period required to maintain compliance with facility covenants							6,649,276,000
Revolving credit borrowings							402,284,000			753,932,000
Wells Fargo Bank Group Credit Facility [Member] | Federal Funds [Member]
Line of Credit Facility [Line Items]
Line of credit facility, spread on variable rate basis				0.50%
Wells Fargo Bank Group Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Line of credit facility, spread on variable rate basis				1.00%
Wells Fargo Bank Group Credit Facility Tranche One [Member]
Line of Credit Facility [Line Items]
Line of credit facility, expiration date				Dec. 31, 2021
Line of credit facility, commitment										200,000,000
Revolving credit borrowings										164,242,000	$ 50,000,000
Wells Fargo Bank Group Credit Facility Tranche Two [Member]
Line of Credit Facility [Line Items]
Line of credit facility, expiration date				Dec. 31, 2021	Dec. 31, 2021
Line of credit facility, commitment							600,000,000			600,000,000
Revolving credit borrowings							402,284,000			589,690,000
Wells Fargo Bank Bilateral Loc Agreement [Member]
Line of Credit Facility [Line Items]
Line of credit facility, expiration date				Dec. 31, 2021
Line of credit facility, commitment							500,000,000	$ 500,000,000	$ 50,000,000
Revolving credit borrowings							404,421,000
Citibank Bilateral Agreement [Member]
Line of Credit Facility [Line Items]
Line of credit facility, term of credit facility				15 months
Line of credit facility, commitment							200,000,000			200,000,000
Percentage of interest on the principal amount of letters of credit issued				0.35%
Percentage of interest on the principal amount of issued extended tenor letters of credit				0.45%
Maximum term allowed to execute issued letters of credit				60 months
Revolving credit borrowings							$ 173,553,000			$ 185,483,000
Lloyds Bank plc Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit facility, commitment | £			£ 52,175,000	£ 52,175,000	£ 52,175,000
Line of credit facility, required debt-to-capital ratio | Rate			35.00%	35.00%			35.00%
Line of credit facility, required minimum net worth							$ 6,393,047,000
Consolidated net worth, percentage						70.00%
Percentage amount of consolidated net income required to be reserved to maintain compliance with facility covenants			25.00%
Percentage amount of increase in consolidated net worth from new issuance required to be reserved to maintain compliance with facility covenants			25.00%
Increase in reserves due to new issuance during the period required to maintain compliance with facility covenants							6,786,229,000
Revolving credit borrowings | £			£ 52,175,000	£ 52,175,000	£ 52,175,000
Federal Home Loan Bank Of New York [Member]
Line of Credit Facility [Line Items]
Admitted assets for FHLB							18,197,177,000
Maximum amount available under FHLB							1,819,717,000
Borrowings from FHLB							400,000,000
Revolving credit borrowings							$ 310,000
FHLB advance interest rate			0.35%	0.35%			0.35%
Amount of borrowed funds required to be used to acquire additional membership stock, percentage				4.50%
Federal Home Loan Bank Of New York [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
FHLB advance maturity				Nov. 30, 2021
Federal Home Loan Bank Of New York [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
FHLB advance maturity				Dec. 31, 2021

Credit Facilities (Summary Of C

Credit Facilities (Summary Of Costs Incurred Connection With Credit Facilities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Line of Credit Facility [Line Items]
Credit facility interest and fees incurred	$ 345	$ 332	$ 721	$ 455
Active Credit Facilities [Member]
Line of Credit Facility [Line Items]
Credit facility interest and fees incurred	70	332	175	455
Federal Home Loan Bank Of New York [Member]
Line of Credit Facility [Line Items]
Credit facility interest and fees incurred	$ 275		$ 546

Credit Facilities (Summary Of O

Credit Facilities (Summary Of Outstanding Letters Of Credit And Borrowings) (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2021GBP (£)	Dec. 31, 2020GBP (£)	Jun. 30, 2021USD ($)	May 05, 2021USD ($)	Feb. 23, 2021USD ($)	Dec. 31, 2020USD ($)	Mar. 25, 2020USD ($)	May 26, 2016USD ($)	Jun. 22, 2012USD ($)
Line of Credit Facility [Line Items]
Commitment			$ 1,300,000,000
Wells Fargo Bank Group Credit Facility [Member]
Line of Credit Facility [Line Items]
Commitment			600,000,000			$ 800,000,000		$ 800,000,000	$ 800,000,000
In Use			402,284,000			753,932,000
Wells Fargo Bank Group Credit Facility Tranche One [Member]
Line of Credit Facility [Line Items]
Commitment						200,000,000
In Use						164,242,000	$ 50,000,000
Date of Expiry	Dec. 31, 2021
Wells Fargo Bank Group Credit Facility Tranche Two [Member]
Line of Credit Facility [Line Items]
Commitment			600,000,000			600,000,000
In Use			402,284,000			589,690,000
Date of Expiry	Dec. 31, 2021	Dec. 31, 2021
Wells Fargo Bank Bilateral Loc Agreement [Member]
Line of Credit Facility [Line Items]
Commitment			500,000,000	$ 500,000,000	$ 50,000,000
In Use			404,421,000
Date of Expiry	Dec. 31, 2021
Citibank Bilateral Agreement [Member]
Line of Credit Facility [Line Items]
Commitment			200,000,000			200,000,000
In Use			173,553,000			185,483,000
Citibank Bilateral Letter Of Credit Agreement One [Member]
Line of Credit Facility [Line Items]
Commitment			200,000,000			200,000,000
In Use			1,264,000			4,425,000
Date of Expiry	Nov. 24, 2021	Feb. 28, 2021
Citibank Bilateral Letter Of Credit Agreement Two [Member]
Line of Credit Facility [Line Items]
In Use			449,000			3,672,000
Date of Expiry	Dec. 16, 2021	Nov. 24, 2021
Citibank Bilateral Letter Of Credit Agreement Three [Member]
Line of Credit Facility [Line Items]
In Use			138,869,000			448,000
Date of Expiry	Dec. 31, 2021	Dec. 16, 2021
Citibank Bilateral Letter Of Credit Agreement Four [Member]
Line of Credit Facility [Line Items]
In Use			4,425,000			115,000
Date of Expiry	Feb. 28, 2022	Dec. 20, 2021
Citibank Bilateral Letter Of Credit Agreement Five [Member]
Line of Credit Facility [Line Items]
In Use			443,000			136,383,000
Date of Expiry	Mar. 1, 2022	Dec. 31, 2021
Citibank Bilateral Letter Of Credit Agreement Six [Member]
Line of Credit Facility [Line Items]
In Use			822,000			39,619,000
Date of Expiry	Aug. 15, 2022	Dec. 30, 2024
Citibank Bilateral Letter Of Credit Agreement Seven [Member]
Line of Credit Facility [Line Items]
In Use			155,000			821,000
Date of Expiry	Dec. 20, 2022	Aug. 15, 2022
Citibank Bilateral Letter Of Credit Agreement Eight [Member]
Line of Credit Facility [Line Items]
In Use			27,126,000
Date of Expiry	Jun. 30, 2025
Lloyds Bank plc Credit Facility [Member]
Line of Credit Facility [Line Items]
Commitment | £	£ 52,175,000	£ 52,175,000
In Use | £	52,175,000	52,175,000
Lloyd's Bank Issuance One [Member]
Line of Credit Facility [Line Items]
Commitment | £	£ 52,175,000	£ 52,175,000
In Use			$ 52,175,000			$ 52,175,000
Date of Expiry	Dec. 31, 2024	Dec. 31, 2023

Collateralized Reinsurance An_3

Collateralized Reinsurance And Trust Agreements (Narrative) (Details) - USD ($) $ in Thousands	Apr. 01, 2018	Jun. 30, 2021	Dec. 31, 2020
Effects of Reinsurance [Line Items]
Amount on deposit in trust accounts		$ 1,418,185
Preferred shares
Reinsurance recoverable		228,727,000	254,907
Deferred gain liabliity		$ 36,064	38,782
Mt Logan Re [Member]
Effects of Reinsurance [Line Items]
Percentage of voting common shares owned by Group		100.00%
Assumed net risk exposures		$ 831,634	806,564
Net risk exposure investments		$ 67,881	$ 67,645
Retrocede amount	$ 269,198
Cash transferred	252,000
Mt Logan Re [Member] | Minimum [Member]
Effects of Reinsurance [Line Items]
Accident year		2002
Mt Logan Re [Member] | Maximum [Member]
Effects of Reinsurance [Line Items]
Accident year		2015
Liability retroceded	$ 319,000

Collateralized Reinsurance An_4

Collateralized Reinsurance And Trust Agreements (Premiums And Losses Ceded By The Company To Affiliate) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Effects of Reinsurance [Line Items]
Ceded written premiums	$ 56,183	$ 48,522	$ 155,293	$ 158,710
Ceded earned premiums	71,422	71,143	149,529	161,693
Ceded losses and LAE	31,052	40,936	111,895	86,051
Assumed written premiums	2,741	2,795	5,217	5,554
Assumed earned premiums	2,741	2,795	5,217	5,554
Assumed losses and LAE

Collateralized Reinsurance An_5

Collateralized Reinsurance And Trust Agreements (Summary of Collateralized Reinsurance Agreements) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Effects of Reinsurance [Line Items]
Limit	$ 56,183	$ 48,522	$ 155,293	$ 158,710
Kilimanjaro Re Limited [Member] | Series 2017-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 13, 2017
Expiration Date			Apr. 13, 2022
Limit			$ 50,000
Kilimanjaro Re Limited [Member] | Series 2017-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 13, 2017
Expiration Date			Apr. 13, 2022
Limit			$ 75,000
Kilimanjaro Re Limited [Member] | Series 2017-1 Class C-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 13, 2017
Expiration Date			Apr. 13, 2022
Limit			$ 175,000
Kilimanjaro Re Limited [Member] | Series 2018-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 30, 2018
Expiration Date			May 6, 2022
Limit			$ 62,500
Kilimanjaro Re Limited [Member] | Series 2018-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 30, 2018
Expiration Date			May 6, 2022
Limit			$ 200,000
Kilimanjaro Re Limited [Member] | Series 2018-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 30, 2018
Expiration Date			May 5, 2023
Limit			$ 62,500
Kilimanjaro Re Limited [Member] | Series 2018-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 30, 2018
Expiration Date			May 5, 2023
Limit			$ 200,000
Kilimanjaro Re Limited [Member] | Series 2019-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Dec. 12, 2019
Expiration Date			Dec. 19, 2023
Limit			$ 150,000
Kilimanjaro Re Limited [Member] | Series 2019-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Dec. 12, 2019
Expiration Date			Dec. 19, 2023
Limit			$ 275,000
Kilimanjaro Re Limited [Member] | Series 2019-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Dec. 12, 2019
Expiration Date			Dec. 19, 2024
Limit			$ 150,000
Kilimanjaro Re Limited [Member] | Series 2019-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Dec. 12, 2019
Expiration Date			Dec. 19, 2024
Limit			$ 275,000
Kilimanjaro Re Limited [Member] | Series 2020-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 8, 2021
Expiration Date			Apr. 21, 2025
Limit			$ 150,000
Kilimanjaro Re Limited [Member] | Series 2020-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 8, 2021
Expiration Date			Apr. 21, 2025
Limit			$ 85,000
Kilimanjaro Re Limited [Member] | Series 2020-1 Class C-1 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 8, 2021
Expiration Date			Apr. 21, 2025
Limit			$ 85,000
Kilimanjaro Re Limited [Member] | Series 2020-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 8, 2021
Expiration Date			Apr. 20, 2026
Limit			$ 150,000
Kilimanjaro Re Limited [Member] | Series 2020-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 8, 2021
Expiration Date			Apr. 20, 2026
Limit			$ 90,000
Kilimanjaro Re Limited [Member] | Series 2020-1 Class C-2 [Member]
Effects of Reinsurance [Line Items]
Effective Date			Apr. 8, 2021
Expiration Date			Apr. 20, 2026
Limit			$ 90,000

Collateralized Reinsurance An_6

Collateralized Reinsurance And Trust Agreements (Schedule of Proceeds from Issuance of Notes Held in Reinsurance Trusts) (Details) - Kilimanjaro Re Limited [Member] $ in Thousands	6 Months Ended
	Jun. 30, 2021USD ($)
Series 2017-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 13, 2017
Maturity Date	Apr. 13, 2022
Amount	$ 50,000
Series 2017-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 13, 2017
Maturity Date	Apr. 13, 2022
Amount	$ 75,000
Series 2017-1 Class C-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 13, 2017
Maturity Date	Apr. 13, 2022
Amount	$ 175,000
Series 2018-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 6, 2022
Amount	$ 62,500
Series 2018-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 6, 2022
Amount	$ 200,000
Series 2018-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 5, 2023
Amount	$ 62,500
Series 2018-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 30, 2018
Maturity Date	May 5, 2023
Amount	$ 200,000
Series 2019-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2023
Amount	$ 150,000
Series 2019-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2023
Amount	$ 275,000
Series 2019-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2024
Amount	$ 150,000
Series 2019-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Dec. 12, 2019
Maturity Date	Dec. 19, 2024
Amount	$ 275,000
Series 2020-1 Class A-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 8, 2021
Maturity Date	Apr. 21, 2025
Amount	$ 150,000
Series 2020-1 Class B-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 8, 2021
Maturity Date	Apr. 21, 2025
Amount	$ 85,000
Series 2020-1 Class C-1 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 8, 2021
Maturity Date	Apr. 21, 2025
Amount	$ 85,000
Series 2020-1 Class A-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 8, 2021
Maturity Date	Apr. 20, 2026
Amount	$ 150,000
Series 2020-1 Class B-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 8, 2021
Maturity Date	Apr. 20, 2026
Amount	$ 90,000
Series 2020-1 Class C-2 [Member]
Effects of Reinsurance [Line Items]
Issue Date	Apr. 8, 2021
Maturity Date	Apr. 20, 2026
Amount	$ 90,000

Senior Notes (Narrative) (Detai

Senior Notes (Narrative) (Details) - Senior Notes [Member] - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
4.868% Senior Notes due 6/1/2044 [Member]
Debt Instrument [Line Items]
Date issued	Jun. 5, 2014
Debt instrument face amount	$ 400,000
Debt instrument, term	30 years
Debt instrument, stated interest rate	4.868%
Debt instrument, maturity date	Jun. 1, 2044	Jun. 1, 2044
3.5% Senior notes due 10/15/2050 [Member]
Debt Instrument [Line Items]
Date issued	Oct. 7, 2020
Debt instrument face amount	$ 1,000,000
Debt instrument, term	30 years
Debt instrument, stated interest rate	3.50%
Debt instrument, maturity date	Oct. 15, 2050	Oct. 15, 2050

Senior Notes (Schedule Of Outst

Senior Notes (Schedule Of Outstanding Senior Notes) (Details) - Senior Notes [Member] - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
4.868% Senior Notes due 6/1/2044 [Member]
Debt Instrument [Line Items]
Date issued	Jun. 5, 2014
Date due	Jun. 1, 2044	Jun. 1, 2044
Original Principal Amount	$ 400,000
Consolidated Balance Sheet Amount	397,254	$ 397,194
Market Value	$ 505,284	$ 528,000
Debt instrument, stated interest rate	4.868%
3.5% Senior notes due 10/15/2050 [Member]
Debt Instrument [Line Items]
Date issued	Oct. 7, 2020
Date due	Oct. 15, 2050	Oct. 15, 2050
Original Principal Amount	$ 1,000,000
Consolidated Balance Sheet Amount	979,784	$ 979,524
Market Value	$ 1,068,990	$ 1,138,100
Debt instrument, stated interest rate	3.50%

Senior Notes (Schedule Of Inter

Senior Notes (Schedule Of Interest Expense Incurred In Connection With Senior Notes) (Details) - Senior Notes [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
4.868% Senior Notes due 6/1/2044 [Member]
Debt Instrument [Line Items]
Interest expense incurred	$ 4,868	$ 4,868	$ 9,736	$ 9,736
Debt instrument, stated interest rate	4.868%		4.868%
3.5% Senior notes due 10/15/2050 [Member]
Debt Instrument [Line Items]
Interest expense incurred	$ 8,805		$ 17,610
Debt instrument, stated interest rate	3.50%		3.50%

Long Term Subordinated Notes (N

Long Term Subordinated Notes (Narrative) (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2021USD ($)Item	Jun. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Aug. 15, 2021
Debt Instrument [Line Items]
Redemption date			May 1, 2047
Subordinated Debt [Member]
Debt Instrument [Line Items]
Percentage of principal amount required for redemption			100.00%
Outstanding debt reduction			$ 161,441,000
Gain on repurchase and retirement of debt					$ 13,183,000
Subordinated Debt [Member] | 6.6 % Long Term Subordinated Notes [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest rate	6.60%		6.60%
Interest payment commencement date			Nov. 15, 2007
Basis spread on variable rate			2.385%
Right to defer interest, number of occasions | Item			1
Debt instrument, maturity date			May 1, 2067		May 1, 2067
Outstanding debt reduction	$ 0	$ 11,483,000	$ 0	$ 13,183,000
Gain on repurchase and retirement of debt		$ 2,034,000		$ 2,536,000
Subordinated Debt [Member] | 6.6 % Long Term Subordinated Notes [Member] | Scenario Forecast [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest rate						2.54%
Subordinated Debt [Member] | 6.6 % Long Term Subordinated Notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest payment date			May 3, 2007
Subordinated Debt [Member] | 6.6 % Long Term Subordinated Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest payment date			May 14, 2017
Right to defer interest on one or more occasions for up to number of consecutive years			10 years
Senior Notes [Member] | 5.4% Senior notes due 10/15/2014 [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest rate	5.40%		5.40%
Debt instrument, maturity date			Oct. 15, 2014
Senior Notes [Member] | 4.868% Senior Notes due 6/1/2044 [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest rate	4.868%		4.868%
Debt instrument, maturity date			Jun. 1, 2044		Jun. 1, 2044
Senior Notes [Member] | 3.5% Senior notes due 10/15/2050 [Member]
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.50%		3.50%
Debt instrument, maturity date			Oct. 15, 2050		Oct. 15, 2050

Long Term Subordinated Notes (S

Long Term Subordinated Notes (Schedule Of Outstanding Fixed To Floating Rate Long Term Subordinated Notes) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Consolidated balance sheet amount	$ 223,724	$ 223,674
Senior Notes [Member] | 4.868% Senior Notes due 6/1/2044 [Member]
Debt Instrument [Line Items]
Date Issued	Jun. 5, 2014
Original Principal Amount	$ 400,000
Maturity Date	Jun. 1, 2044	Jun. 1, 2044
Market Value	$ 505,284	$ 528,000
Senior Notes [Member] | 3.5% Senior notes due 10/15/2050 [Member]
Debt Instrument [Line Items]
Date Issued	Oct. 7, 2020
Original Principal Amount	$ 1,000,000
Maturity Date	Oct. 15, 2050	Oct. 15, 2050
Market Value	$ 1,068,990	$ 1,138,100
Subordinated Debt [Member] | 6.6 % Long Term Subordinated Notes [Member]
Debt Instrument [Line Items]
Date Issued	Apr. 26, 2007
Original Principal Amount	$ 400,000
Maturity Date	May 1, 2067	May 1, 2067
Consolidated balance sheet amount	$ 223,724	$ 223,674
Market Value	$ 214,772	$ 206,447
Scheduled [Member] | Subordinated Debt [Member] | 6.6 % Long Term Subordinated Notes [Member]
Debt Instrument [Line Items]
Maturity Date	May 15, 2037

Long Term Subordinated Notes _2

Long Term Subordinated Notes (Schedule Of Interest Expense Incurred In Connection With Long Term Subordinated Notes) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Debt Instrument [Line Items]
Interest expense incurred	$ 1,460,000	$ 2,000,000	$ 2,922,000	$ 4,539,000
Subordinated Debt [Member] | Debt Instrument Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.60%		6.60%

Segment Reporting (Narrative) (

Segment Reporting (Narrative) (Details)	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Percentage threshold of Company revenue not exceeded by any other country	5.00%

Segment Reporting (Schedule Of

Segment Reporting (Schedule Of Underwriting Results For Operating Segments) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Premiums earned	$ 2,558,372	$ 2,042,405	$ 4,946,237	$ 4,079,219
Incurred losses and LAE	1,586,141	1,407,016	3,297,560	2,837,856
Commission and brokerage	557,749	466,316	1,046,760	914,838
Other underwriting expenses	140,844	118,130	283,075	246,990
Underwriting gain (loss)	273,639	50,943	318,843	79,535
U.S. Reinsurance [Member]
Segment Reporting Information [Line Items]
Gross written premium	2,148,235	1,538,348	4,207,250	3,316,119
Net written premiums	2,059,919	1,424,089	3,972,868	3,037,183
Premiums earned	1,920,801	1,502,256	3,698,253	2,987,476
Incurred losses and LAE	1,168,139	1,005,677	2,440,045	2,026,319
Commission and brokerage	473,258	387,339	881,982	757,695
Other underwriting expenses	47,065	39,698	99,061	83,837
Underwriting gain (loss)	232,339	69,542	277,165	119,625
Insurance [Member]
Segment Reporting Information [Line Items]
Gross written premium	1,041,905	830,990	1,914,323	1,624,090
Net written premiums	749,492	593,389	1,390,479	1,181,774
Premiums earned	637,571	540,149	1,247,984	1,091,743
Incurred losses and LAE	418,002	401,339	857,515	811,537
Commission and brokerage	84,490	78,977	164,777	157,143
Other underwriting expenses	93,779	78,432	184,014	163,153
Underwriting gain (loss)	$ 41,300	$ (18,599)	$ 41,678	$ (40,090)

Segment Reporting (Schedule O_2

Segment Reporting (Schedule Of Underwriting Results For Operating Segments To Income (Loss) Before Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Underwriting gain (loss)	$ 273,639	$ 50,943	$ 318,843	$ 79,535
Net investment income	407,095	38,083	667,508	185,883
Net realized capital gains (losses)	104,109	184,648	143,011	(25,940)
Corporate expenses	(16,168)	(8,733)	(28,546)	(18,566)
Interest, fee and bond issue cost amortization expense	(15,607)	(7,253)	(31,246)	(14,836)
Other income (expense)	7,114	(20,621)	63,707	(12,631)
INCOME (LOSS) BEFORE TAXES	$ 760,181	$ 237,067	$ 1,133,276	$ 193,445

Segment Reporting (Schedule O_3

Segment Reporting (Schedule Of Gross Written Premiums Derived From Largest Non-U.S. Market) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
United Kingdom [Member]
Segment Reporting Information [Line Items]
Gross written premium	$ 249,314	$ 236,100	$ 615,462	$ 542,808

Share-Based Compensation Plans

Share-Based Compensation Plans (Narrative) (Details) - $ / shares	May 12, 2021	Feb. 24, 2021	Feb. 23, 2021	Jun. 30, 2021	Jun. 30, 2021
Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period	2,275	10,656	194,610	2,275	207,541
Weighted-average grant-date fair value of options granted	$ 264.845	$ 244.445	$ 242.24
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period			22,205
Weighted-average grant-date fair value of options granted			$ 242.24

Retirement Benefits (Narrative)

Retirement Benefits (Narrative) (Details) - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Defined Benefit Pension Plan [Member] | Qualified Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 0	$ 0

Retirement Benefits (Net Period

Retirement Benefits (Net Periodic Benefit Cost For U.S. Employees) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2,738,000	$ 2,041,000	$ 5,476,000	$ 6,052,000
Interest cost	1,999,000	2,563,000	3,998,000	5,046,000
Expected return on assets	(5,580,000)	(5,197,000)	(11,161,000)	(10,394,000)
Amortization of net (income) loss	2,731,000	2,462,000	5,461,000	3,675,000
Net periodic benefit cost	1,888	1,869	3,774,000	4,379,000
Post-Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	281,000	311,000	564,000	452,000
Interest cost	181,000	215,000	362,000	429,000
Amortization of prior service cost	(144,000)	(176,000)	(289,000)	(224,000)
Net periodic benefit cost	$ 318,000	$ 350,000	$ 637,000	$ 657,000