AXIS Capital Holdings Limited (AXS) 10-Q 26 Apr 23 2023 Q1 Quarterly report Financial data

COVER

COVER - shares	3 Months Ended
	Mar. 31, 2023	Apr. 21, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2023
Document Transition Report	false
Entity File Number	001-31721
Entity Registrant Name	AXIS CAPITAL HOLDINGS LTD
Entity Incorporation, State or Country Code	D0
Entity Tax Identification Number	98-0395986
Entity Address, Address Line One	92 Pitts Bay Road
Entity Address, City or Town	Pembroke
Entity Address, Country	BM
Entity Address, Postal Zip Code	HM 08
City Area Code	441
Local Phone Number	496-2600
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
Entity Common Stock, Shares Outstanding		85,199,909
Amendment flag	false
Document fiscal year focus	2023
Document fiscal period focus	Q1
Entity central index key	0001214816
Current fiscal year-end date	--12-31
Common shares
Document Information [Line Items]
Title of 12(b) Security	Common shares, par value $0.0125 per share
Trading Symbol	AXS
Security Exchange Name	NYSE
Depositary Shares, each representing a 1/100th interest in a 5.50% Series E preferred share
Document Information [Line Items]
Title of 12(b) Security	Depositary shares, each representing a 1/100th interest in a 5.50% Series E preferred share
Trading Symbol	AXS PRE
Security Exchange Name	NYSE

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Investments:
Fixed maturities, available for sale, at fair value (Amortized cost 2023: $12,264,498; 2022: $12,176,473 Allowance for expected credit losses 2023: $12,645; 2022: $11,733)	$ 11,627,555	$ 11,326,894
Fixed maturities, held to maturity, at amortized cost (Fair value 2023: $696,775; 2022: $674,743 Allowance for expected credit losses 2023: $nil; 2022: $nil)	716,768	698,351
Equity securities, at fair value (Cost 2023: $559,293; 2022: $494,356)	573,916	485,253
Mortgage loans, held for investment, at fair value (Allowance for expected credit losses 2023: $1,900; 2022: $nil)	634,470	627,437
Other investments, at fair value	1,008,887	996,751
Equity method investments	146,083	148,288
Short-term investments, at fair value	70,416	70,310
Total investments	14,778,095	14,353,284
Cash and cash equivalents	816,917	751,415
Restricted cash and cash equivalents	362,378	423,238
Accrued interest receivable	97,983	94,418
Insurance and reinsurance premium balances receivable (Allowance for expected credit losses 2023: $9,528; 2022: $9,521)	3,119,158	2,733,464
Reinsurance recoverable on unpaid losses and loss expenses (Allowance for expected credit losses 2023: $32,347; 2022: $30,715)	5,823,417	5,831,172
Reinsurance recoverable on paid losses and loss expenses	593,013	539,676
Deferred acquisition costs	560,173	473,569
Prepaid reinsurance premiums	1,632,513	1,550,370
Receivable for investments sold	7,079	16,052
Goodwill	100,801	100,801
Intangible assets	195,071	197,800
Operating lease right-of-use assets	88,155	92,214
Other assets	390,224	438,338
Total assets	28,564,977	27,595,811
Liabilities
Reserve for losses and loss expenses	15,314,644	15,168,863
Unearned premiums	4,821,775	4,361,447
Insurance and reinsurance balances payable	1,574,608	1,522,764
Debt	1,312,658	1,312,314
Federal Home Loan Bank advances	85,790	81,388
Payable for investments purchased	78,711	19,693
Operating lease liabilities	99,130	102,577
Other liabilities	317,432	386,855
Total liabilities	23,604,748	22,955,901
Shareholders’ equity
Preferred shares	550,000	550,000
Common shares (shares issued 2023: 176,580; 2022: 176,580 shares outstanding 2023: 85,183; 2022: 84,668)	2,206	2,206
Additional paid-in capital	2,347,637	2,366,253
Accumulated other comprehensive income (loss)	(571,896)	(760,300)
Retained earnings	6,381,201	6,247,022
Treasury shares, at cost (2023: 91,397; 2022: 91,912)	(3,748,919)	(3,765,271)
Total shareholders’ equity	4,960,229	4,639,910
Total liabilities and shareholders’ equity	$ 28,564,977	$ 27,595,811

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Amortized cost	$ 12,264,498	$ 12,176,473
Fixed maturities, available for sale, allowance for credit loss	12,645	11,733
Fixed maturities, held to maturity, fair value	696,775	674,743
Fixed maturities, held to maturity, allowance for credit loss	0	0
Equity securities, cost	559,293	494,356
Allowance for expected credit losses	1,900	0
Allowance for expected credit losses on insurance and reinsurance premium balances receivable	9,528	9,521
Allowance for expected credit losses on reinsurance recoverable for unpaid losses and loss expenses	$ 32,347	$ 30,715
Common shares, shares issued (in shares)	176,580	176,580
Common shares, shares outstanding (in shares)	85,183	84,668
Treasury shares, shares (in shares)	91,397	91,912

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenues
Net premiums earned	$ 1,230,199	$ 1,258,246
Net investment income	133,771	91,355
Other insurance related income	577	6,693
Net investment losses:
(Increase) decrease in allowance for expected credit losses	(2,811)	(70)
Impairment losses	0	(109)
Other realized and unrealized investment losses	(17,379)	(94,329)
Total net investment losses	(20,190)	(94,508)
Total revenues	1,344,357	1,261,786
Expenses
Net losses and loss expenses	720,642	732,699
Acquisition costs	230,373	248,352
General and administrative expenses	166,811	169,041
Foreign exchange losses (gains)	8,710	(44,273)
Interest expense and financing costs	16,894	15,564
Amortization of intangible assets	2,729	2,729
Total expenses	1,146,159	1,124,112
Income before income taxes and interest in income (loss) of equity method investments	198,198	137,674
Income tax expense	(15,896)	(24)
Interest in income (loss) of equity method investments	(2,205)	11,550
Net income	180,097	149,200
Preferred share dividends	7,563	7,563
Net income available to common shareholders	$ 172,534	$ 141,637
Earnings per common share:
Earnings per common share (in usd per share)	$ 2.03	$ 1.67
Earnings per diluted common share (in usd per share)	$ 2.01	$ 1.65
Weighted average common shares outstanding (in shares)	84,864	84,961
Weighted average diluted common shares outstanding (in shares)	85,853	85,808

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 180,097	$ 149,200
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) arising during the period, net of reclassification adjustment	188,939	(397,611)
Foreign currency translation adjustment	(535)	2,775
Total other comprehensive income (loss), net of tax	188,404	(394,836)
Comprehensive income (loss)	368,501	(245,636)
Unrealized gains (losses) on available for sale investments
Other comprehensive income (loss), net of tax:
Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss)	40,750	45,343
Unrealized gains (losses) arising during the period, net of reclassification adjustment	188,939	(397,611)
Unrealized gains (losses) on available for sale investments | Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has not been recognized
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) arising during period	134,567	(442,722)
Unrealized gains (losses) on available for sale investments | Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has been recognized
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) arising during period	$ 13,622	$ (232)

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands		Total	Preferred shares	Common shares (par value)	Additional paid-in capital	Accumulated other comprehensive income (loss)	Unrealized gains (losses) on available for sale investments, net of tax:	Cumulative foreign currency translation adjustments, net of tax:	Retained earnings	Treasury shares, at cost
Balance at beginning of period at Dec. 31, 2021			$ 550,000	$ 2,206	$ 2,346,179	$ 56,536	$ 62,155	$ (5,619)	$ 6,204,745	$ (3,749,010)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares reissued					(29,378)					30,923
Share-based compensation expense					12,185
Unrealized gains (losses) arising during the period, net of reclassification adjustment		$ (397,611)					(397,611)
Foreign currency translation adjustment		2,775						2,775
Net income		149,200							149,200
Preferred share dividends	[1]								(7,563)
Common share dividends	[1]								(37,670)
Shares repurchased										(12,977)
Balance at end of period at Mar. 31, 2022		5,120,540	550,000	2,206	2,328,986	(338,300)	(335,456)	(2,844)	6,308,712	(3,731,064)
Balance at beginning of period at Dec. 31, 2022		4,639,910	550,000	2,206	2,366,253	(760,300)	(743,695)	(16,605)	6,247,022	(3,765,271)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares reissued					(30,593)					32,297
Share-based compensation expense					11,977
Unrealized gains (losses) arising during the period, net of reclassification adjustment		188,939					188,939
Foreign currency translation adjustment		(535)						(535)
Net income		180,097							180,097
Preferred share dividends	[1]								(7,563)
Common share dividends	[1]								(38,355)
Shares repurchased										(15,945)
Balance at end of period at Mar. 31, 2023		$ 4,960,229	$ 550,000	$ 2,206	$ 2,347,637	$ (571,896)	$ (554,756)	$ (17,140)	$ 6,381,201	$ (3,748,919)
[1]Refer to Note 9 'Shareholders' Equity' for details on dividends declared and paid related to the Company's common and preferred shares.

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net income	$ 180,097	$ 149,200
Adjustments to reconcile net income to net cash provided by operating activities:
Net investment losses	20,190	94,508
Net realized and unrealized gains on other investments	(486)	(25,643)
Amortization of fixed maturities	(2,425)	10,896
Interest in income (loss) of equity method investments	2,205	(11,550)
Other amortization and depreciation	14,971	15,714
Share-based compensation expense, net of cash payments	8,935	7,661
Changes in:
Accrued interest receivable	(3,826)	(654)
Reinsurance recoverable on unpaid losses and loss expenses	6,675	60,605
Reinsurance recoverable on paid losses and loss expenses	(53,728)	30,441
Deferred acquisition costs	(88,700)	(111,635)
Prepaid reinsurance premiums	(80,592)	(176,010)
Reserve for losses and loss expenses	150,410	(182,720)
Unearned premiums	462,751	736,045
Insurance and reinsurance balances, net	(337,675)	(345,837)
Other items	(56,368)	(117,710)
Net cash provided by operating activities	222,434	133,311
Purchases of:
Fixed maturities, available for sale	(1,614,005)	(2,287,937)
Fixed maturities, held to maturity	(20,001)	(50,992)
Equity securities	(77,560)	(2,218)
Mortgage loans	(14,030)	(42,802)
Other investments	(26,308)	(37,311)
Short-term investments	(54,895)	(50,896)
Proceeds from the sale of:
Fixed maturities, available for sale	1,330,744	2,255,915
Equity securities	13,162	50,097
Other investments	14,825	57,300
Short-term investments	44,949	6,042
Proceeds from redemption of fixed maturities, available for sale	221,094	416,838
Proceeds from redemption of fixed maturities, held to maturity	1,596	3,500
Proceeds from redemption of short-term investments	10,520	5,530
Proceeds from the repayment of mortgage loans	5,206	9,982
Proceeds from the sale (purchase) of other assets, net	5,299	(10,431)
Net cash provided by (used in) investing activities	(159,404)	322,617
Cash flows from financing activities:
Taxes paid on withholding shares	(15,945)	(12,977)
Dividends paid - common shares	(40,323)	(39,743)
Dividends paid - preferred shares	(7,563)	(7,563)
Federal Home Loan Bank advances, net	5,250	0
Net cash used in financing activities	(58,581)	(60,283)
Effect of exchange rate changes on foreign currency cash, cash equivalents and restricted cash	193	(6,624)
Increase in cash, cash equivalents and restricted cash	4,642	389,021
Cash, cash equivalents and restricted cash - beginning of period	1,174,653	1,317,690
Cash, cash equivalents and restricted cash - end of period	1,179,295	1,706,711
Supplemental disclosures of cash flow information:
Income taxes paid (refund)	(2,403)	346
Interest paid	$ 17,110	$ 16,263

BASIS OF PRESENTATION AND SIGNI

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2023
Accounting Policies [Abstract]
BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	Basis of Presentation These unaudited consolidated financial statements (the "financial statements") have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the U.S. Securities and Exchange Commission's ("SEC") instructions to Form 10-Q and Article 10 of Regulation S-X and include AXIS Capital Holdings Limited ("AXIS Capital") and its subsidiaries (the "Company"). Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. This Quarterly Report on Form 10-Q should be read in conjunction with the financial statements and related notes included in AXIS Capital's Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the SEC. In the opinion of management, these financial statements reflect all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation of the Company's financial position and results of operations for the periods presented. The results of operations for any interim period are not necessarily indicative of the results for a full year. All inter-company accounts and transactions have been eliminated. Tabular dollar and share amounts are in thousands, with the exception of per share amounts. All amounts are reported in U.S. dollars. Significant Accounting Policies There were no notable changes to the Company's significant accounting policies subsequent to its Annual Report on Form 10-K for the year ended December 31, 2022.

SEGMENT INFORMATION

SEGMENT INFORMATION	3 Months Ended
	Mar. 31, 2023
Segment Reporting [Abstract]
SEGMENT INFORMATION	The Company's underwriting operations are organized around its global underwriting platforms, AXIS Insurance and AXIS Re. The Company has determined that it has two reportable segments, insurance and reinsurance. The Company does not allocate its assets by segment, with the exception of goodwill and intangible assets. Insurance The Company's insurance segment offers specialty insurance products to a variety of niche markets on a worldwide basis. The product lines in this segment are professional lines, property, liability, cyber, marine and aviation, accident and health, and credit and political risk. Reinsurance The Company's reinsurance segment provides treaty reinsurance to insurance companies on a worldwide basis. The product lines in this segment are liability, accident and health, professional lines, credit and surety, motor, agriculture, marine and aviation, catastrophe, property and engineering. The following tables present the underwriting results of the Company's reportable segments, as well as the carrying amounts of allocated goodwill and intangible assets: 2023 2022 Three months ended and at March 31, Insurance Reinsurance Total Insurance Reinsurance Total Gross premiums written $ 1,415,612 $ 966,364 $ 2,381,976 $ 1,327,264 $ 1,307,344 $ 2,634,608 Net premiums written 882,576 725,780 1,608,356 843,912 968,960 1,812,872 Net premiums earned 816,456 413,743 1,230,199 752,816 505,430 1,258,246 Other insurance related income 54 523 577 82 6,611 6,693 Net losses and loss expenses (449,467) (271,175) (720,642) (405,745) (326,954) (732,699) Acquisition costs (147,058) (83,315) (230,373) (138,812) (109,540) (248,352) Underwriting-related general and administrative expenses (116,630) (23,765) (140,395) (113,950) (31,146) (145,096) Underwriting income $ 103,355 $ 36,011 139,366 $ 94,391 $ 44,401 138,792 Net investment income 133,771 91,355 Net investment losses (20,190) (94,508) Corporate expenses (26,416) (23,945) Foreign exchange (losses) gains (8,710) 44,273 Interest expense and financing costs (16,894) (15,564) Amortization of intangible assets (2,729) (2,729) Income before income taxes and interest in income (loss) of equity method investments 198,198 137,674 Income tax expense (15,896) (24) Interest in income (loss) of equity method investments (2,205) 11,550 Net income 180,097 149,200 Preferred share dividends 7,563 7,563 Net income available to common shareholders $ 172,534 $ 141,637 Net losses and loss expenses ratio 55.1 % 65.5 % 58.6 % 53.9 % 64.7 % 58.2 % Acquisition cost ratio 18.0 % 20.1 % 18.7 % 18.4 % 21.7 % 19.7 % General and administrative expense ratio 14.2 % 5.8 % 13.6 % 15.2 % 6.1 % 13.5 % Combined ratio 87.3 % 91.4 % 90.9 % 87.5 % 92.5 % 91.4 % Goodwill and intangible assets $ 295,872 $ — $ 295,872 $ 306,789 $ — $ 306,789

INVESTMENTS

INVESTMENTS	3 Months Ended
	Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract]
INVESTMENTS	a) Fixed Maturities, Available for Sale The following table provides the amortized cost and fair values of the Company's fixed maturities classified as available for sale: Amortized cost Allowance for expected credit losses Gross Gross unrealized losses Fair value At March 31, 2023 Available for sale U.S. government and agency $ 2,956,074 $ — $ 15,733 $ (70,495) $ 2,901,312 Non-U.S. government 587,923 (28) 3,511 (33,329) 558,077 Corporate debt 4,619,198 (12,436) 12,264 (321,814) 4,297,212 Agency RMBS (1) 1,344,187 — 9,111 (81,137) 1,272,161 CMBS (2) 996,699 — 165 (73,361) 923,503 Non-agency RMBS 145,288 (98) 134 (15,839) 129,485 ABS (3) 1,454,488 (36) 828 (57,897) 1,397,383 Municipals (4) 160,641 (47) 317 (12,489) 148,422 Total fixed maturities, available for sale $ 12,264,498 $ (12,645) $ 42,063 $ (666,361) $ 11,627,555 At December 31, 2022 Available for sale U.S. government and agency $ 2,731,733 $ — $ 5,386 $ (97,789) $ 2,639,330 Non-U.S. government 612,546 — 2,395 (52,912) 562,029 Corporate debt 4,680,798 (11,521) 5,269 (418,990) 4,255,556 Agency RMBS (1) 1,297,423 — 4,663 (99,301) 1,202,785 CMBS (2) 1,029,863 — 60 (82,145) 947,778 Non-agency RMBS 151,907 (123) 275 (18,525) 133,534 ABS (3) 1,499,728 (35) 555 (70,721) 1,429,527 Municipals (4) 172,475 (54) 139 (16,205) 156,355 Total fixed maturities, available for sale $ 12,176,473 $ (11,733) $ 18,742 $ (856,588) $ 11,326,894 (1) Residential mortgage-backed securities ("RMBS") originated by U.S. government-sponsored agencies. (2) Commercial mortgage-backed securities ("CMBS"). (3) Asset-backed securities ("ABS") include debt tranched securities collateralized primarily by auto loans, student loans, credit card receivables and collateralized loan obligations ("CLOs"). (4) Municipals include bonds issued by states, municipalities and political subdivisions. Contractual Maturities Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. The table below provides the contractual maturities of fixed maturities classified as available for sale: Amortized cost Fair value % of Total fair value At March 31, 2023 Maturity Due in one year or less $ 576,989 $ 563,123 4.9 % Due after one year through five years 5,400,687 5,204,250 44.8 % Due after five years through ten years 2,171,234 1,974,369 17.0 % Due after ten years 174,926 163,281 1.4 % 8,323,836 7,905,023 68.1 % Agency RMBS 1,344,187 1,272,161 10.9 % CMBS 996,699 923,503 7.9 % Non-agency RMBS 145,288 129,485 1.1 % ABS 1,454,488 1,397,383 12.0 % Total $ 12,264,498 $ 11,627,555 100.0 % At December 31, 2022 Maturity Due in one year or less $ 422,039 $ 409,972 3.7 % Due after one year through five years 5,349,123 5,078,273 44.8 % Due after five years through ten years 2,192,344 1,919,450 16.9 % Due after ten years 234,046 205,575 1.8 % 8,197,552 7,613,270 67.2 % Agency RMBS 1,297,423 1,202,785 10.6 % CMBS 1,029,863 947,778 8.4 % Non-agency RMBS 151,907 133,534 1.2 % ABS 1,499,728 1,429,527 12.6 % Total $ 12,176,473 $ 11,326,894 100.0 % Gross Unrealized Losses The following table summarizes fixed maturities, available for sale in an unrealized loss position and the aggregate fair value and gross unrealized loss by length of time the security has continuously been in an unrealized loss position: 12 months or greater Less than 12 months Total Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses At March 31, 2023 Fixed maturities, available for sale U.S. government and agency $ 808,593 $ (51,696) $ 738,852 $ (18,799) $ 1,547,445 $ (70,495) Non-U.S. government 263,740 (31,114) 109,543 (2,215) 373,283 (33,329) Corporate debt 2,499,437 (287,339) 1,166,503 (34,475) 3,665,940 (321,814) Agency RMBS 533,145 (64,620) 433,607 (16,517) 966,752 (81,137) CMBS 764,365 (66,063) 140,843 (7,298) 905,208 (73,361) Non-agency RMBS 99,758 (15,383) 23,591 (456) 123,349 (15,839) ABS 1,179,697 (56,118) 134,693 (1,779) 1,314,390 (57,897) Municipals 105,115 (11,526) 31,816 (963) 136,931 (12,489) Total fixed maturities, available for sale $ 6,253,850 $ (583,859) $ 2,779,448 $ (82,502) $ 9,033,298 $ (666,361) At December 31, 2022 Fixed maturities, available for sale U.S. government and agency $ 467,032 $ (41,365) $ 1,414,181 $ (56,424) $ 1,881,213 $ (97,789) Non-U.S. government 207,637 (33,027) 298,048 (19,885) 505,685 (52,912) Corporate debt 1,562,355 (268,289) 2,350,504 (150,701) 3,912,859 (418,990) Agency RMBS 220,595 (40,469) 771,191 (58,832) 991,786 (99,301) CMBS 343,494 (40,888) 599,877 (41,257) 943,371 (82,145) Non-agency RMBS 75,137 (14,691) 53,484 (3,834) 128,621 (18,525) ABS 685,990 (48,913) 686,190 (21,808) 1,372,180 (70,721) Municipals 52,994 (10,120) 96,003 (6,085) 148,997 (16,205) Total fixed maturities, available for sale $ 3,615,234 $ (497,762) $ 6,269,478 $ (358,826) $ 9,884,712 $ (856,588) At March 31, 2023, 4,372 fixed maturities (2022: 4,525) were in an unrealized loss position of $666 million (2022: $857 million), of which $47 million (2022: $64 million) was related to securities below investment grade or not rated. At March 31, 2023 , 3,154 fixed maturities (2022: 1,842) had been in a continuous unrealized loss position for twelve months or greater and had a fair value of $6,254 million (2022 : $3,615 million ). The unrealized loss es of $666 million (2022: $857 million) were due to non-credit factors and were expected to be recovered as the related securities approach maturity. At March 31, 2023, the Company did not intend to sell the securities in an unrealized loss position and it is more likely than not that the Company will not be required to sell these securities before the anticipated recovery of their amortized costs. b) Fixed Maturities, Held to Maturity The following table provides the amortized cost and fair values of the Company's fixed maturities classified as held to maturity: Amortized cost Allowance for expected credit losses Net carrying value Gross Gross unrealized losses Fair value At March 31, 2023 Held to maturity Corporate debt $ 85,200 $ — $ 85,200 $ — $ (9,535) $ 75,665 ABS (1) 631,568 — 631,568 — (10,458) 621,110 Total fixed maturities, held to maturity $ 716,768 $ — $ 716,768 $ — $ (19,993) $ 696,775 At December 31, 2022 Held to maturity Corporate debt $ 85,200 $ — $ 85,200 $ — $ (11,428) $ 73,772 ABS (1) 613,151 — 613,151 — (12,180) 600,971 Total fixed maturities, held to maturity $ 698,351 $ — $ 698,351 $ — $ (23,608) $ 674,743 (1) Asset-backed securities ("ABS") include debt tranched securities collateralized primarily by collateralized loan obligations ("CLOs"). At March 31, 2023, fixed maturities, held to maturity of $717 million (2022: $698 million ) were presented net of an allowance for expected credit losse s of $nil (2022: $nil). The Company's ABS, held to maturity consist of CLO debt tranched securities. The Company uses a scenario-based approach to review its CLO debt portfolio and reviews subordination levels of these securities to determine their ability to absorb credit losses of the underlying collateral. If losses are forecast to be below the subordination level for a tranche held by the Company, the security is determined not to have a credit loss. At March 31, 2023, the allowance for credit losses expected to be recognized over the life of the Company's ABS, held to maturity w as $nil. To estimate expected credit losses for corporate debt securities, held to maturity, the Company's projected cash flows are primarily driven by assumptions regarding the severity of loss, which is a function of the probability of default and projected recovery rates. The Company's default and recovery rates are based on credit ratings, credit analysis and macroeconomic forecasts. At March 31, 2023, the allowance for credit losses expected to be recognized over the life of the Company's corporate debt, held to m aturity was $nil. Contractual Maturities ABS classified as held to maturity with a net carrying value of $632 million (2022: $613 million) do not have a single maturity date and cannot be allocated over several maturity groupings. Corpo rate debt classified as held to maturity with a net carrying value of $81 million (2022: $81 million) is due between 3 years and 10 years and corporate debt classified as held to maturity with a net carrying value of $4 million (2022: $4 million) is due after ten years. c) Equity Securities The following table provides the cost and fair values of the Company's equity securities: Cost Gross unrealized gains Gross unrealized losses Fair value At March 31, 2023 Equity securities Common stocks $ 3,130 $ 321 $ (437) $ 3,014 Preferred stocks 115 — (113) 2 Exchange-traded funds 199,212 83,523 (3,016) 279,719 Bond mutual funds 356,836 50 (65,705) 291,181 Total equity securities $ 559,293 $ 83,894 $ (69,271) $ 573,916 At December 31, 2022 Equity securities Common stocks $ 7,279 $ 636 $ (442) $ 7,473 Preferred stocks 115 — (43) 72 Exchange-traded funds 207,505 68,058 (5,757) 269,806 Bond mutual funds 279,457 — (71,555) 207,902 Total equity securities $ 494,356 $ 68,694 $ (77,797) $ 485,253 d) Mortgage Loans The following table provides details of the Company's mortgage loans, held for investment: March 31, 2023 December 31, 2022 Carrying value % of Total Carrying value % of Total Mortgage loans, held for investment: Commercial $ 636,370 100 % $ 627,437 100 % Allowance for expected credit losses (1,900) — % — — % Total mortgage loans, held for investment $ 634,470 100 % $ 627,437 100 % The primary credit quality indicators for commercial mortgage loans are the debt service coverage ratio which compares a property’s net operating income to amounts needed to service the principal and interest due under the loan, (generally, the lower the debt service coverage ratio, the higher the risk of experiencing a credit loss) and the loan-to-value ratio which compares the unpaid principal balance of the loan to the estimated fair value of the underlying collateral (generally, the higher the loan-to-value ratio, the higher the risk of experiencing a credit loss). The debt service coverage ratio and loan-to-value ratio, as well as the values utilized in calculating these ratios, are updated quarterly. The Company has a high quality mortgage loan portfolio with a weighted average debt service coverage ratio of 2.2x (2022: 2.3x) and a weighted average loan-to-value ratio of 60% (2022: 60%). At March 31, 2023, and 2022 there were no past due amounts associated with the commercial mortgage loans held by the Company. On a quarterly basis, collateral dependent mortgage loans (e.g, when the borrower is experiencing financial difficulty, including when foreclosure is reasonably possible or probable) are evaluated individually for credit losses. The allowance for expected credit losses for a collateral dependent loan is established as the excess of amortized cost over the estimated fair value of the loan's underlying collateral, less selling cost when foreclosure is probable. Accordingly, the change in the estimated fair value of collateral dependent loans, which are evaluated individually for credit losses, is recognized as a change in the allowance for expected credit losses which is recorded in net investment gains (losses). At March 31, 2023, there is one collateral dependent loan with a loan-to-value ratio in excess of 100%, resulting in an allowance for expected credit loss of $2 million. e) Other Investments The following table provides a summary of the Company's other investments, together with additional information relating to the liquidity of each category: Fair value % of Total Redemption frequency (if currently eligible) Redemption notice period At March 31, 2023 Multi-strategy funds $ 30,721 3 % Quarterly 60-90 days Direct lending funds 258,183 26 % Quarterly (1) 90 days Private equity funds 273,859 27 % n/a n/a Real estate funds 300,152 30 % Quarterly (2) , Annually (3) 45-90 days CLO-Equities 5,019 — % n/a n/a Other privately held investments 140,953 14 % n/a n/a Total other investments $ 1,008,887 100 % At December 31, 2022 Multi-strategy funds $ 32,616 3 % Quarterly 60-90 days Direct lending funds 258,626 26 % Quarterly (1) 90 days Private equity funds 265,836 27 % n/a n/a Real estate funds 298,499 30 % Quarterly (2) , Annually (3) 45-90 days CLO-Equities 5,016 — % n/a n/a Other privately held investments 136,158 14 % n/a n/a Total other investments $ 996,751 100 % n/a - not applicable (1) Applies to one fund with a fair va lue of $35 million (2022: $39 million). (2) Applies to one fund with a fair value of $72 million (2022: $73 million ). (3) Applies to one fund with a fair value of $25 million (2022: $27 million ). Two common redemption restrictions which may impact the Company's ability to redeem hedge funds are gates and lockups. A gate is a suspension of redemptions which may be implemented by the general partner or investment manager of the fund in order to defer, in whole or in part, the redemption request in the event the aggregate amount of redemption requests exceeds a predetermined percentage of the fund's net assets which may otherwise hinder the general partner or investment manager's ability to liquidate holdings in an orderly fashion in order to generate the cash necessary to fund extraordinarily large redemption payouts. A lockup period is the initial amount of time an investor is contractually required to hold the security before having the ability to redeem. During the three months ended March 31, 2023 and 2022, neither of these restrictions impacted the Company's redemption requests. At March 31, 2023, there w ere no hedg e fund holdings (2022: $nil) where the Company is still within the lockup period. At March 31, 2023, the Company h ad $26 million (2022: $26 million) of unfunded commitments as a limited partner in multi-strategy hedge funds. Once the full amount of committed capital has been called by the General Partner of each of these funds, the assets will not be fully returned until after the completion of the funds' investment term. These funds have investment terms ranging from two years to the dissolution of the underlying fund. At March 31, 2023, the Company had $197 million (2022: $183 million) of unfunded commitments as a limited partner in direct lending funds. Once the full amount of committed capital has been called by the General Partner of each of these funds, the assets will not be fully returned until the completion of the fund's investment term. These funds have investment terms ranging from four At March 31, 2023, the Company had $166 million (2022: $158 million) of unfunded commitments as a limited partner in private equity funds. The life of the funds is subject to the dissolution of the underlying funds. The Company expects the overall holding period to be over five years. At March 31, 2023, the Company had $136 million (2022: $141 million) of unfunded commitments as a limited partner in real estate funds. These funds include an open-ended fund and funds with investment terms ranging from two years to the dissolution of the underlying fund. f) Equity Method Investments During 2016, the Company paid $108 million including direct transaction costs to acquire 19% of the common equity of Harrington Reinsurance Holdings Limited ("Harrington"), the parent company of Harrington Re Ltd. ("Harrington Re"), an independent reinsurance company jointly sponsored by the Company and The Blackstone Group L.P. ("Blackstone"). Through long-term service agreements, the Company will serve as Harrington Re's reinsurance underwriting manager and Blackstone will serve as exclusive investment management service provider. As an investor, the Company expects to benefit from underwriting profit generated by Harrington Re and the income and capital appreciation Blackstone seeks to deliver through its investment management services. In addition, the Company has entered into an arrangement with Blackstone under which underwriting and investment related fees will be shared equally. Harrington is not a Variable Interest Entities ("VIE") that is required to be included in the Company's consolidated financial statements. The Company accounts for its ownership interest in Harrington under the equity method of accounting. The Company's proportionate share of the underlying equity in net assets resulted in a basis difference of $5 million which represents initial transactions costs. g) Variable Interest Entities In the normal course of investing activities, the Company actively manages allocations to non-controlling tranches of structured securities which are variable interests issued by Variable Interest Entities ("VIEs"). These structured securities include RMBS, CMBS and ABS. The Company also invests in limited partnerships which represent 71% of the Company's other investments. The investments in limited partnerships include hedge funds, direct lending funds, private equity funds and real estate funds and CLO equity tranched securities, which are variable interests issued by VIEs (refer to Note 3(c) ' Other Investments '). The Company does not have the power to direct the activities that are most significant to the economic performance of these VIEs therefore the Company is not the primary beneficiary of these VIEs. The maximum exposure to loss on these interests is limited to the amount of commitment made by the Company. The Company has not provided financial or other support to these structured securities other than the original investment. h) Net Investment Income Net investment income was derived from the following sources: Three months ended March 31, 2023 2022 Fixed maturities $ 118,262 $ 64,809 Other investments 486 26,050 Equity securities 2,455 2,172 Mortgage loans 8,386 4,163 Cash and cash equivalents 10,012 1,118 Short-term investments 1,660 166 Gross investment income 141,261 98,478 Investment expenses (7,490) (7,123) Net investment income $ 133,771 $ 91,355 i) Net Investment Gains (Losses) The following table provides an analysis of net investment gains (losses): Three months ended March 31, 2023 2022 Gross realized investment gains Fixed maturities and short-term investments $ 12,370 $ 10,422 Equity securities 1,517 — Gross realized investment gains 13,887 10,422 Gross realized investment losses Fixed maturities and short-term investments (53,649) (63,146) Equity securities (396) (225) Gross realized investment losses (54,045) (63,371) (Increase) decrease in allowance for expected credit losses, fixed maturities, available for sale (911) (70) (Increase) decrease in allowance for expected credit losses, mortgage loans (1,900) — Impairment losses (1) — (109) Change in fair value of investment derivatives (2) (947) 2,242 Net unrealized gains (losses) on equity securities 23,726 (43,622) Net investment losses $ (20,190) $ (94,508) (1) Related to instances where the Company intends to sell securities or it is more likely than not that the Company will be required to sell securities before their anticipated recovery. (2) Refer to Note 5 ' Derivative Instruments'. The following table provides a reconciliation of the beginning and ending balances of the allowance for expected credit losses on fixed maturities classified as available for sale: Three months ended March 31, 2023 2022 Balance at beginning of period $ 11,733 $ 313 Expected credit losses on securities where credit losses were not previously recognized 613 9 Additions (reductions) for expected credit losses on securities where credit losses were previously recognized 919 78 Impairments of securities which the Company intends to sell or more likely than not will be required to sell — — Securities sold/redeemed/matured (620) (17) Balance at end of period $ 12,645 $ 383 j) Reverse Repurchase Agreements

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2023
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	Fair Value Hierarchy Fair value is defined as the price to sell an asset or transfer a liability (i.e., the "exit price") in an orderly transaction between market participants. U.S. GAAP prescribes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to quoted prices in active markets and the lowest priority to unobservable data. 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. The hierarchy is broken down into three levels as follows: • Level 1 - Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access. • Level 2 - Valuations based on quoted prices in active markets for similar assets or liabilities, quoted prices for identical assets or liabilities in inactive markets, or for which significant inputs are observable (e.g., interest rates, yield curves, prepayment speeds, default rates, loss severities, etc.) or can be corroborated by observable market data. • Level 3 - Valuations based on inputs that are unobservable and significant to the overall fair value measurement. The unobservable inputs reflect the Company's judgments about assumptions that market participants might use. The availability of observable inputs can vary from financial instrument to financial instrument and is affected by a wide variety of factors including, for example, the type of financial instrument, whether the financial instrument is new and not yet established in the marketplace, and other characteristics particular to the transaction. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires significantly more judgment. Accordingly, the degree of judgment exercised by management in determining fair value is greatest for financial instruments categorized as Level 3. In periods of market dislocation, the observability of prices and inputs may be reduced for many financial instruments. This may lead the Company to change the selection of valuation technique (from market to cash flow approach) or may cause the Company to use multiple valuation techniques to estimate the fair value of a financial instrument. This circumstance could cause an instrument to be reclassified between levels within the fair value hierarchy. Valuation Techniques The valuation techniques, including significant inputs and assumptions generally used to determine the fair values of the Company's financial instruments as well as the classification of the fair values of its financial instruments in the fair value hierarchy are described in detail below. Fixed Maturities At each valuation date, the Company uses the market approach valuation technique to estimate the fair value of its fixed maturities portfolio, where possible. The market approach includes, but is not limited to, prices obtained from third-party pricing services for identical or comparable securities and the use of "pricing matrix models" using observable market inputs such as yield curves, credit risks and spreads, measures of volatility, and prepayment speeds. Pricing from third-party pricing services is sourced from multiple vendors, where available, and the Company maintains a vendor hierarchy by asset type based on historical pricing experience and vendor expertise. Where prices are unavailable from pricing services, the Company obtains non-binding quotes from broker-dealers who are active in the corresponding markets. The valuation techniques including significant inputs and assumptions generally used to determine the fair values of the Company's fixed maturities by asset class as well as the classifications of the fair values of these securities in the fair value hierarchy are described in detail below. U.S. Government and Agency U.S. government and agency securities consist primarily of bonds issued by the U.S. Treasury and mortgage pass-through agencies such as the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation and the Government National Mortgage Association. As the fair values of U.S. Treasury securities are based on unadjusted quoted market prices in active markets, the fair values of these securities are classified as Level 1. The fair values of U.S. government agency securities are determined using the spread above the risk-free yield curve. As the yields for the risk-free yield curve and the spreads are observable market inputs, the fair values of U.S. government agency securities are classified as Level 2. Non-U.S. Government Non-U.S. government securities include bonds issued by non-U.S. governments and their agencies along with supranational organizations (collectively also known as sovereign debt securities). The fair values of these securities are based on prices obtained from international indices or valuation models that include inputs such as interest rate yield curves, cross-currency basis index spreads, and country credit spreads for structures similar to the sovereign bond in terms of issuer, maturity and seniority. As the significant inputs used to price these securities are observable market inputs, the fair values of non-U.S. government securities are classified as Level 2. Corporate Debt Corporate debt securities consist primarily of investment grade debt of a wide variety of corporate issuers and industries. The fair values of these securities are generally determined using the spread above the risk-free yield curve. These spreads are generally obtained from the new issue market, secondary trading and broker-dealer quotes. As the yields for the risk-free yield curve and the spreads are observable market inputs, the fair values of corporate debt securities are generally classified as Level 2. Where pricing is unavailable from pricing services, the Company obtains non-binding quotes from broker-dealers to estimate fair value. This is generally the case when there is a low volume of trading activity and current transactions are not orderly. In this event, the fair values of these securities are classified as Level 3. Agency RMBS Agency RMBS consist of bonds issued by the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation and the Government National Mortgage Association. The fair values of these securities are priced using a mortgage pool specific model which uses daily inputs from the active to be announced market and the spread associated with each mortgage pool based on vintage. As the significant inputs used to price these securities are observable market inputs, the fair values of Agency RMBS are classified as Level 2. CMBS CMBS mainly include investment grade bonds originated by non-agencies. The fair values of these securities are determined using a pricing model which uses dealer quotes and other available trade information along with security level characteristics to determine deal specific spreads. As the significant inputs used to price these securities are observable market inputs, the fair values of CMBS are generally classified as Level 2. Where pricing is unavailable from pricing services, the Company obtains non-binding quotes from broker-dealers to estimate fair value. This is generally the case when there is a low volume of trading activity and current transactions are not orderly. I n this event, the fair values of these securities are classified as Level 3. Non-agency RMBS Non-agency RMBS mainly include investment grade bonds originated by non-agencies. The fair values of these securities are determined using an option adjusted spread model or other relevant models, which use inputs including available trade information or broker quotes, prepayment and default projections based on historical statistics of the underlying collateral and current market data. As the significant inputs used to price these securities are observable market inputs, the fair values of non-agency RMBS are generally classified as Level 2. Where pricing is unavailable from pricing services, the Company obtains non-binding quotes from broker-dealers to estimate fair value. This is generally the case when there is a low volume of trading activity and current transactions are not orderly. I n this event, the fair values of these securities are classified as Level 3. ABS ABS mainly include investment grade bonds backed by pools of loans with a variety of underlying collateral, including auto loans, student loans, credit card receivables and collateralized loan obligations ("CLOs"), originated by a variety of financial institutions. The fair values of these securities are determined using a model which uses prepayment speeds and spreads sourced primarily from the new issue market. As the significant inputs used to price these securities are observable market inputs, the fair values of ABS are generally classified as Level 2. Where pricing is unavailable from pricing services, the Company obtains non-binding quotes from broker-dealers t o estimate fair value. This is generally the case when there is a low volume of trading activity and current transactions are not orderly. I n this event, the fair values of these securities are classified as Level 3. Municipals Municipals comprise revenue bonds and general obligation bonds issued by U.S. domiciled state and municipal entities. The fair values of these securities are determined using spreads obtained from the new issue market, trade prices and broker-dealers quotes. As the significant inputs used to price these securities are observable market inputs, the fair values of municipals are classified as Level 2. Equity Securities Equity securities include common stocks, preferred stocks, exchange-traded funds and bond mutual funds. As the fair values of common stocks, preferred stocks and exchange-traded funds are based on unadjusted quoted market prices in active markets, the fair values of these securities are classified as Level 1. As bond mutual funds have daily liquidity, the fair values of these securities are classified as Level 2. Other Investments The fair value of an indirect investment in CLO-Equities is estimated using an income approach valuation technique, specifically an externally developed discounted cash flow model due to the lack of observable and relevant trades in secondary markets. As the significant inputs used to price this security are unobservable, the fair value of the indirect investment in CLO-Equities is classified as Level 3. Other privately held investments include convertible preferred shares, preferred shares, common shares, convertible notes, investments in limited partnerships and a variable yield security. These investments are initially valued at cost, which approximates fair value. In subsequent measurement periods, the fair values of these investments are derived from one or a combination of valuation methodologies which consider factors including recent capital raises by the investee companies, comparable precedent transaction multiples, comparable publicly traded multiples, third-party valuations, discounted cash-flow models, and other techniques that consider the industry and development stage of each investee company. The fair value of the variable yield security is determined using an externally developed discounted cash flow model. In order to assess the reasonableness of the information received from investee companies, the Company maintains an understanding of current market conditions, historical results, and emerging trends that may impact the results of operations, financial condition or liquidity of these companies. In addition, the Company engages in regular communication with management at investee companies. As the significant inputs used to price these investments are unobservable, the fair values of other privately held investments are classified as Level 3. Short-term Investments Short-term investments primarily comprise highly liquid securities with maturities greater than three months but less than one year from the date of purchase. These securities are typically not actively traded due to their approaching maturity, therefore their amortized cost approximates fair value. The fair values of short-term investments are classified as Level 2. Derivative Instruments Derivative instruments include foreign exchange forward contracts that are customized to the Company's economic hedging strategies and trade in the over-the-counter derivative market. The fair values of these derivatives are determined using a market approach valuation technique based on significant observable market inputs from third-party pricing vendors, non-binding broker-dealer quotes and/or recent trading activity. As the significant inputs used to price these derivatives are observable market inputs, the fair values of these derivatives are classified as Level 2. Other underwriting-related derivatives include insurance and reinsurance contracts that are accounted for as derivatives. These derivative contracts are initially valued at cost which approximates fair value. In subsequent measurement periods, the fair values of these derivatives are determined using internally developed discounted cash flow models. As the significant inputs used to price these derivatives are unobservable, the fair values of these contracts are classified as Level 3. Cash-Settled Awards Cash-settled awards comprise restricted stock units that form part of the Company's compensation program. Although the fair values of these awards are determined using observable quoted market prices in active markets, the restricted stock units are not actively traded. As the significant inputs used to price these securities are observable market inputs, the fair values of these liabilities are classified as Level 2. The tables below present the financial instruments measured at fair value on a recurring basis for the periods indicated: Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Fair value based on NAV practical expedient Total fair value At March 31, 2023 Assets Fixed maturities, available for sale U.S. government and agency $ 2,862,087 $ 39,225 $ — $ — $ 2,901,312 Non-U.S. government — 558,077 — — 558,077 Corporate debt — 4,166,785 130,427 — 4,297,212 Agency RMBS — 1,272,161 — — 1,272,161 CMBS — 923,503 — — 923,503 Non-agency RMBS — 129,485 — — 129,485 ABS — 1,397,383 — — 1,397,383 Municipals — 148,422 — — 148,422 2,862,087 8,635,041 130,427 — 11,627,555 Equity securities Common stocks 3,014 — — — 3,014 Preferred stocks 2 — — — 2 Exchange-traded funds 279,719 — — — 279,719 Bond mutual funds — 291,181 — — 291,181 282,735 291,181 — — 573,916 Other investments Multi-strategy funds — — — 30,721 30,721 Direct lending funds — — — 258,183 258,183 Private equity funds — — — 273,859 273,859 Real estate funds — — — 300,152 300,152 CLO-Equities — — 5,019 — 5,019 Other privately held investments — — 140,953 — 140,953 — — 145,972 862,915 1,008,887 Short-term investments — 70,416 — — 70,416 Other assets Derivative instruments (refer to Note 5) — 7,752 — — 7,752 Total Assets $ 3,144,822 $ 9,004,390 $ 276,399 $ 862,915 $ 13,288,526 Liabilities Derivative instruments (refer to Note 5) $ — $ 2,789 $ — $ — $ 2,789 Cash-settled awards (refer to Note 8) — — — — — Total Liabilities $ — $ 2,789 $ — $ — $ 2,789 Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Fair value based on NAV practical expedient Total fair value At December 31, 2022 Assets Fixed maturities, available for sale U.S. government and agency $ 2,600,636 $ 38,694 $ — $ — $ 2,639,330 Non-U.S. government — 562,029 — — 562,029 Corporate debt — 4,136,452 119,104 — 4,255,556 Agency RMBS — 1,202,785 — — 1,202,785 CMBS — 947,778 — — 947,778 Non-agency RMBS — 133,534 — — 133,534 ABS — 1,429,527 — — 1,429,527 Municipals — 156,355 — — 156,355 2,600,636 8,607,154 119,104 — 11,326,894 Equity securities Common stocks 7,473 — — — 7,473 Preferred stocks 72 — — — 72 Exchange-traded funds 269,806 — — — 269,806 Bond mutual funds — 207,902 — — 207,902 277,351 207,902 — — 485,253 Other investments Multi-strategy funds — — — 32,616 32,616 Direct lending funds — — — 258,626 258,626 Private equity funds — — — 265,836 265,836 Real estate funds — — — 298,499 298,499 CLO-Equities — — 5,016 — 5,016 Other privately held investments — — 136,158 — 136,158 — — 141,174 855,577 996,751 Short-term investments — 70,310 — — 70,310 Other assets Derivative instruments (refer to Note 5) — 37,682 — — 37,682 Total Assets $ 2,877,987 $ 8,923,048 $ 260,278 $ 855,577 $ 12,916,890 Liabilities Derivative instruments (refer to Note 5) $ — $ 703 $ — $ — $ 703 Cash-settled awards (refer to Note 8) — 4,792 — — 4,792 Total Liabilities $ — $ 5,495 $ — $ — $ 5,495 The following table quantifies the significant unobservable inputs used in estimating fair values at March 31, 2023 of investments classified as Level 3 in the fair value hierarchy: Asset fair value Valuation technique Unobservable input Amount / Range Weighted average Other investments - CLO-Equities $ 5,019 Discounted cash flow Default rate 4.5% 4.5% Loss severity rate 50.0% 50.0% Collateral spread 3.0% 3.0% Estimated maturity date 5 years 5 years Other investments - Other privately held investments $ 17,522 Discounted cash flow Discount rate 6.6% 6.6% Default rate 0.5% 0.5% Loss absorption yield 1.0% 1.0% Estimated maturity date 1-3 years 2 years Note: Fixed maturities of $130 million that are classified as Level 3 are excluded from the above table as these securities are priced using broker-dealer quotes. In addition, other privately held investments of $123 million that are classified as Level 3 are excluded from the above table as these investments are priced using capital statements received from investee companies. Other Investments - CLO-Equities The CLO-Equities market continues to be relatively inactive with only a small number of transactions being observed, particularly related to transactions involving CLO-Equities held by the Company. Accordingly, the fair value of the Company's indirect investment in CLO-Equities is determined using a discounted cash flow model prepared by an external investment manager. The default and loss severity rates are the most judgmental unobservable market inputs to the discounted cash flow model to which the valuation of the Company's indirect investment in CLO-Equities is most sensitive. A significant increase (decrease) in either of these significant inputs in isolation would result in a lower (higher) fair value estimate for the investment in CLO-Equities and, in general, a change in default rate assumptions would be accompanied by a directionally similar change in loss severity rate assumptions. Collateral spreads and estimated maturity dates are less judgmental inputs as they are based on the historical average of actual spreads and the weighted average life of the current underlying portfolios, respectively. A significant increase (decrease) in either of these significant inputs in isolation would result in a higher (lower) fair value estimate for the investment in CLO-Equities. In general, these inputs have no significant interrelationship with each other or with default and loss severity rates. On a quarterly basis, the Company's valuation process for its indirect investment in CLO-Equities includes a review of the underlying cash flows and key assumptions used in the discounted cash flow model. The above significant unobservable inputs are reviewed and updated based on information obtained from secondary markets, including information received from the managers of the Company's CLO-Equities investment. In order to assess the reasonableness of the inputs the Company uses in the discounted cash flow model, the Company maintains an understanding of current market conditions, historical results, and emerging trends that may impact future cash flows. In addition, the assumptions the Company uses in its models are updated through regular communication with industry participants and ongoing monitoring of the deals in which the Company participates. Other Investments - Other Privately Held Securities Other privately held securities are initially valued at cost which approximates fair value. In subsequent measurement periods, the fair value of the variable yield security was determined using an externally developed discounted cash flow model. This model includes inputs that are specific to that investment. The inputs used in the fair value measurement include an appropriate discount rate, default rate, loss absorption rate and estimated maturity date. The selection of an appropriate discount rate is judgmental and is the most significant unobservable input used in the valuation of this investment. A significant increase (decrease) in this input in isolation could result in significantly lower (higher) fair value measurement for this investment. In order to assess the reasonableness of the inputs the Company uses in the discounted cash flow model, the Company maintains an understanding of current market conditions, historical results, as well as investee specific information that may impact future cash flows. The following table presents changes in Level 3 for financial instruments measured at fair value on a recurring basis: Opening balance Transfers into Level 3 Transfers out of Level 3 Included in net income (1) Included in OCI (2) Purchases Sales Settlements/ distributions Closing balance Change in unrealized gains/(losses) (3) Three months ended March 31, 2023 Fixed maturities, available for sale Corporate debt $ 119,104 $ — $ — $ (7) $ 1,183 $ 18,910 $ — $ (8,763) $ 130,427 $ — 119,104 — — (7) 1,183 18,910 — (8,763) 130,427 — Other investments CLO-Equities 5,016 — — 411 — — — (408) 5,019 411 Other privately held investments 136,158 — — 336 — 4,459 — — 140,953 336 141,174 — — 747 — 4,459 — (408) 145,972 747 Total assets $ 260,278 $ — $ — $ 740 $ 1,183 $ 23,369 $ — $ (9,171) $ 276,399 $ 747 Other liabilities Derivative instruments $ — $ — $ — $ — $ — $ — $ — $ — $ — $ — Total liabilities $ — $ — $ — $ — $ — $ — $ — $ — $ — $ — Three months ended March 31, 2022 Fixed maturities, available for sale Corporate debt $ 42,894 $ — $ — $ — $ (2,794) $ 21,462 $ — $ (672) $ 60,890 $ — 42,894 — — — (2,794) 21,462 — (672) 60,890 — Other investments CLO-Equities 5,910 — — 872 — — — (1,901) 4,881 872 Other privately held investments 104,521 — — 1,618 — 9,335 — — 115,474 1,618 110,431 — — 2,490 — 9,335 — (1,901) 120,355 2,490 Total assets $ 153,325 $ — $ — $ 2,490 $ (2,794) $ 30,797 $ — $ (2,573) $ 181,245 $ 2,490 Other liabilities Derivative instruments $ 5,630 $ — $ — $ (556) $ — $ — $ — $ — $ 5,074 $ (556) Total liabilities $ 5,630 $ — $ — $ (556) $ — $ — $ — $ — $ 5,074 $ (556) (1) Realized gains (losses) on fixed maturities and realized and unrealized gains (losses) on other assets and other liabilities included in net income are included in net investment gains (losses). Realized and unrealized gains (losses) on other investments included in net income are included in net investment income. (2) Unrealized gains (losses) on fixed maturities are included in other comprehensive income ("OCI"). (3) Change in unrealized gains (losses) relating to assets and liabilities held at the reporting date. Transfers into Level 3 from Level 2 There were no transfers into Level 3 from Level 2 during the three months ended March 31, 2023 and 2022. Transfers out of Level 3 into Level 2 There were no transfers out of Level 3 into Level 2 during the three months ended March 31, 2023 and 2022. Measuring the Fair Value of Other Investments Using Net Asset Valuations The fair values of hedge funds, direct lending funds, private equity funds and real estate funds are estimated using net asset valuations ("NAVs") as advised by external fund managers or third-party administrators. For these funds, NAVs are based on the manager's or administrator's valuation of the underlying holdings in accordance with the fund's governing documents and in accordance with U.S. GAAP. For hedge funds, direct lending funds, private equity funds and real estate funds, valuation statements are typically released on a reporting lag, therefore, the Company estimates the fair value of these funds by starting with the most recent fund valuations and adjusting for capital calls, redemptions, drawdowns and distributions. Return estimates are not available from the relevant fund managers for these funds, therefore the Company typically has a reporting lag in its fair value measurements of these funds. At March 31, 2023 and December 31, 2022 all funds measured at fair value using NAVs are reported generally on a one quarter lag. The Company often does not have access to financial information relating to the underlying securities held within the funds, therefore, management is unable to corroborate the fair values placed on the securities underlying the asset valuations provided by fund managers or fund administrators. In order to assess the reasonableness of the NAVs, the Company performs a number of monitoring procedures on a quarterly basis, to assess the quality of the information provided by fund managers and fund administrators. These procedures include, but are not limited to, regular review and discussion of each fund's performance with its manager, regular evaluation of fund performance against applicable benchmarks and the backtesting of the Company's fair value estimates against subsequently received NAVs. Backtesting involves comparing the Company's previously reported fair values for each fund against NAVs per audited financial statements (for year-end values) and final NAVs from fund managers and fund administrators (for interim values). The fair values of hedge funds, direct lending funds, private equity funds and real estate funds are measured using the NAV practical expedient, therefore the fair values of these funds have not been categorized within the fair value hierarchy. Financial Instruments Disclosed, But Not Carried, at Fair Value The fair value of financial instruments accounting guidance also applies to financial instruments disclosed, but not carried, at fair value, except for certain financial instruments, including insurance contracts. At March 31, 2023, the carrying values of cash and cash equivalents including restricted amounts, accrued investment income, receivable for investments sold, certain other assets, payable for investments purchased and certain other liabilities approximated fair values due to their short maturities. As these financial instruments are not actively traded, their fair values are classified as Level 2. At March 31, 2023, the Company's fixed maturities, held to maturity, were recorded at amortized cost with a carrying value of $717 million (2022: $698 million) and a fair value of $697 million (2022: $675 million). The fair values of these securities are determined using a model which uses prepayment speeds and spreads sourced primarily from the new issue market. As the significant inputs used to price these securities are observable market inputs, their fair values are classified as Level 2. At March 31, 2023, the carrying value of mortgage loans, held for investment, approximated fair value. The fair values of mortgage loans are primarily determined by estimating expected future cash flows and discounting them using current interest rates for similar mortgage loans with similar credit risk or are determined from pricing for similar loans. As mortgage loans are not actively traded, their fair values are classified as Level 3. At March 31, 2023, the Company's debt was recorded at amortized cost with a carrying value of $1,313 million (2022: $1,312 million) and a fair value of $1,188 million (2022: $1,160 million). The fair value of the Company's debt is based on prices obtained from a third-party pricing service and is determined using the spread above the risk-free yield curve. These spreads are generally obtained from the new issue market, secondary trading and broker-dealer quotes. As the yields for the risk-free yield curve and the spreads are observable market inputs, the fair value of this debt is classified as Level 2. At March 31, 2023, Federal Home Loan Bank advances were recorded at amortized cost with a carrying value of $86 million (2022: $81 million) and a fair value of $86 million (2022: $81 million). As these advances are not actively traded, their fair values are classified as Level 2.

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	3 Months Ended
	Mar. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	The following table provides the balance sheet classifications of derivatives recorded at fair value: March 31, 2023 December 31, 2022 Derivative notional amount Derivative asset fair value (1) Derivative liability fair value (1) Derivative notional amount Derivative asset fair value (1) Derivative liability fair value (1) Relating to investment portfolio: Foreign exchange forward contracts $ 51,959 $ — $ 1,244 $ 54,076 $ 81 $ 559 Relating to underwriting portfolio: Foreign exchange forward contracts 1,318,403 7,752 1,545 1,441,273 37,601 144 Total derivatives $ 7,752 $ 2,789 $ 37,682 $ 703 (1) Derivative assets and derivative liabilities are classified within other assets and other liabilities in the consolidated balance sheets. The notional amounts of derivative contracts represent the basis on which amounts paid or received are calculated and are presented in the above table to quantify the volume of the Company's derivative activities. Notional amounts are not reflective of credit risk. None of the Company's derivative instruments are designated as hedges. Offsetting Assets and Liabilities The Company's derivative instruments are generally traded under International Swaps and Derivatives Association master netting agreements which establish terms that apply to all transactions. In the event of a bankruptcy or other stipulated event, master netting agreements provide that individual positions be replaced with a new amount, usually referred to as the termination amount, determined by taking into account market prices and converting into a single currency. Effectively, this contractual close-out netting reduces credit exposure from gross to net exposure. The following table provides a reconciliation of gross derivative assets and liabilities to the net amounts presented in the consolidated balance sheets, with the difference being attributable to the impact of master netting agreements: March 31, 2023 December 31, 2022 Gross amounts Gross amounts offset Net amounts (1) Gross amounts Gross amounts offset Net amounts (1) Derivative assets $ 11,632 $ (3,880) $ 7,752 $ 41,762 $ (4,080) $ 37,682 Derivative liabilities $ 6,669 $ (3,880) $ 2,789 $ 4,783 $ (4,080) $ 703 (1) Net asset and liability derivatives are classified within other assets and other liabilities in the consolidated balance sheets. Refer to Note 3 'Investments' for information on reverse repurchase agreements. a) Relating to Investment Portfolio Foreign Currency Risk The Company's investment portfolio is exposed to foreign currency risk therefore the fair values of its investments are partially influenced by changes in foreign exchange rates. The Company may enter into foreign exchange forward contracts to manage the effect of this foreign currency risk. These foreign currency hedging activities are not designated as specific hedges for financial reporting purposes. b) Relating to Underwriting Portfolio Foreign Currency Risk The Company's insurance and reinsurance subsidiaries and branches operate in various countries. Some of its business is written in currencies other than the U.S. dollar, therefore the underwriting portfolio is exposed to significant foreign currency risk. The Company manages foreign currency risk by seeking to match its foreign-denominated net liabilities under insurance and reinsurance contracts with cash and investments that are denominated in the same currencies. The Company uses derivative instruments, specifically, forward contracts to economically hedge foreign currency exposures. Other Underwriting-related Risks The Company enters into insurance and reinsurance contracts that are accounted for as derivatives. These insurance or reinsurance contracts provide indemnification to an insured or cedant as a result of a change in a variable as opposed to an identifiable insurable event. The Company considers these contracts to be part of its underwriting operations. The following table provides the total unrealized and realized gains (losses) recognized in net income (loss) for derivatives not designated as hedges: Consolidated statement of operations line item that includes gain (loss) recognized in net income (loss) Three months ended March 31, 2023 2022 Relating to investment portfolio: Foreign exchange forward contracts Net investment gains (losses) $ (947) $ 2,242 Relating to underwriting portfolio: Foreign exchange forward contracts Foreign exchange (losses) gains 11,250 (27,976) Other underwriting-related contracts Other insurance related income (loss) — 555 Total $ 10,303 $ (25,179)

RESERVE FOR LOSSES AND LOSS EXP

RESERVE FOR LOSSES AND LOSS EXPENSES	3 Months Ended
	Mar. 31, 2023
Insurance [Abstract]
RESERVE FOR LOSSES AND LOSS EXPENSES	Reserve Roll-Forward The following table presents a reconciliation of the Company's beginning and ending gross reserve for losses and loss expenses and net reserve for unpaid losses and loss expenses: Three months ended March 31, 2023 2022 Gross reserve for losses and loss expenses, beginning of period $ 15,168,863 $ 14,653,094 Less reinsurance recoverable on unpaid losses and loss expenses, beginning of period (5,831,172) (5,017,611) Net reserve for unpaid losses and loss expenses, beginning of period 9,337,691 9,635,483 Net incurred losses and loss expenses related to: Current year 724,680 741,655 Prior years (4,038) (8,956) 720,642 732,699 Net paid losses and loss expenses related to: Current year (38,662) (32,477) Prior years (574,538) (750,969) (613,200) (783,446) Foreign exchange and other 46,094 (71,661) Net reserve for unpaid losses and loss expenses, end of period 9,491,227 9,513,075 Reinsurance recoverable on unpaid losses and loss expenses, end of period 5,823,417 4,957,080 Gross reserve for losses and loss expenses, end of period $ 15,314,644 $ 14,470,155 The Company writes business with loss experience generally characterized as low frequency and high severity in nature, which can result in volatility in its financial results. During the three months ended March 31, 2023, the Company recognized catastrophe and weather-related losses, net of reinstatement premiums, of $38 million (2022: $60 million). Estimates for Significant Catastrophe Events At March 31, 2023, net reserves for losses and loss expenses included estimated amounts for numerous catastrophe events. The magnitude and complexity of losses arising from certain of these events inherently increase the level of uncertainty and, therefore, the level of management judgment involved in arriving at estimated net reserves for losses and loss expenses. These events include New Zealand floods and Cyclone Gabrielle in 2023, Hurricane Ian, Winter Storm Elliot, June European Convective Storms, the Russia-Ukraine war and COVID-19 in 2022, Hurricane Ida, U.S. Winter Storms Uri and Viola and July European Floods in 2021, and the COVID-19 pandemic, Hurricanes Laura, Sally, Zeta and Delta, the Midwest derecho and wildfires across the West Coast of the United States in 2020. As a result, actual losses for these events may ultimately differ materially from current estimates. Prior Year Reserve Development The Company's net favorable prior year reserve development arises from changes to estimates of losses and loss expenses related to loss events that occurred in previous calendar years. The following table presents net prior year reserve development by segment: Net Favorable Prior Year Reserve Development Insurance Reinsurance Total Three months ended March 31, 2023 $ 1,041 $ 2,997 $ 4,038 Three months ended March 31, 2022 $ 7,062 $ 1,894 $ 8,956 The following sections provide further details on net prior year reserve development by segment, line of business and accident year: Insurance Segment: The following table maps the Company's lines of business to expected claim tails: Insurance segment Expected claims tail Short Medium Long Lines of business Property X Accident and health X Marine and aviation X Cyber X Professional lines X Credit and political risk X Liability X Prior year reserve development by line of business was as follows: Three months ended March 31, 2023 2022 Favorable (Adverse) Favorable (Adverse) Property $ 5,900 $ 8,060 Accident and health (304) 3,632 Marine and aviation 13,221 14,647 Cyber 8,452 (687) Professional lines (12,594) (5,936) Credit and political risk 4,519 895 Liability (18,153) (13,549) Total $ 1,041 $ 7,062 For the three months ended March 31, 2023, the Company recognized $1 million of net favorable prior year reserve development, the principal components of which were: • $13 million of net favorable prior year reserve development on marine and aviation business primarily due to better than expected loss emergence mainly related to 2021 and 2022 accident years. • $8 million of net favorable prior year reserve development on cyber business primarily due to better than expected loss emergence mainly related to 2019 and older accident years. • $6 million of net favorable prior year reserve development on property business primarily due to better than expected loss emergence attributable to 2018 and older accident years, partially offset by reserve strengthening related to the 2021 accident year . • $5 million of net favorable prior year reserve development on credit and political risk business primarily due to a decrease in the loss estimate attributable to a specific large claim related to the 2020 accident year and better than expected loss emergence attributable to the Lloyds book of business related to several accident years. • $18 million of net adverse prior year reserve developmen t on liability business primarily due to reserve strengthening within the U.S. primary casualty book of business mainly related to the 2015, 2018 and 2021 accident years. • $13 million of net adverse prior year reserve development on professional lines business primarily due to reserve strengthening within the U.S. commercial management solutions book of business mainly related to several accident years and U.S. financial institutions book of business mainly related to the 2018 accident year. For the three months ended March 31, 2022, the Company recognized $7 million of net favorable prior year reserve development, the principal components of which were: • $15 million of net favorable prior year reserve development on marine and aviation business primarily due to better than expected loss emergence attributable to the marine cargo and marine offshore energy books of business mainly related to the 2018 and 2021 accident years . • $8 million of net favorable prior year reserve development on property business primarily due to decreases in loss estimates attributable to specific large claims related to the 2017 accident year, and better than expected loss emergence attributable to 2018 catastrophe events. • $14 million of net adverse prior year reserve development on liability business primarily due to reserve strengthening within the program book of business mainly related to the 2016 and 2018 accident years and an increase in the loss estimate attributable to a specific large claim related to the 2017 accident year. • $6 million of net adverse prior year reserve development on professional lines business primarily due to increases in loss estimates attributable to specific large claims related to the 2015 and 2017 accident years, and reserve strengthening within runoff lines of business mainly related to the 2016 and 2018 accident years. Reinsurance Segment: The following table maps the Company's lines of business to expected claim tails: Reinsurance segment Expected claims tail Short Medium Long Lines of business Accident and health X Agriculture X Marine and aviation X Professional lines X Credit and surety X Motor X Liability X Run-off lines Catastrophe X Property X Engineering X Prior year reserve development by line of business was as follows: Three months ended March 31, 2023 2022 Favorable Favorable Accident and health $ 6,988 $ (499) Agriculture 11,891 1,231 Marine and aviation (250) 497 Professional lines (3,225) (24,522) Credit and surety (546) 7,465 Motor (17,122) (1,730) Liability (32,853) (4,105) Run-off lines Catastrophe 31,058 (246) Property 6,883 22,539 Engineering 173 1,264 Total run-off lines 38,114 23,557 Total $ 2,997 $ 1,894 For the three months ended March 31, 2023, the Company recognized $3 million of net favorable prior year reserve development, the principal components of which were: • $12 million of net favorable development on agriculture business primarily due to better than expected loss emergence mainly related to the 2022 accident year. • $7 million of net favorable development on accident and health business primarily due to better than expected loss emergence mainly related to the 2022 accident year. • $33 million of net adverse development on liability business primarily due to reserve strengthening to reflect increased estimates of future loss trend due to inflation, increases in loss estimates attributable to one large claim within the European book of business related to the 2021 accident year and reserve strengthening within the U.S. proportional book of business related to 2019 and older accident years. • $17 million of net adverse development on motor business primarily due to reserve strengthening to reflect increased estimates of future loss trend due to inflation. Run-off lines • $31 million of net favorable development on catastrophe business primarily due to better than expected loss emergence mainly related to the 2022 accident year. • $7 million of net favorable development on property business primarily due to better than expected loss emergence attributable to 2022 catastrophe events. For the three months ended March 31, 2022, the Company recognized $2 million of net favorable prior year reserve development, the principal components of which were: • $7 million of net favorable prior year reserve development on credit and surety business primarily due to better than expected loss emergence related to recent accidents years. • $25 million of net adverse prior year development on professional lines business primarily due to an increase in loss estimates attributable to one cedant related to the 2016 to 2018 accident years and a specific large claim related to the 2017 accident year. • $4 million of net adverse prior year development on liability business primarily due to an increase in loss estimates attributable to a specific large claim related to the 2018 accident year. Run-off lines • $23 million of net favorable prior year development on property business primarily due to better than expected loss emergence attributable to 2018, 2019 and 2021 catastrophe events, and an aggregate excess of loss treaty.

EARNINGS PER COMMON SHARE

EARNINGS PER COMMON SHARE	3 Months Ended
	Mar. 31, 2023
Earnings Per Share [Abstract]
EARNINGS PER COMMON SHARE	The following table presents a comparison of earnings per common share and earnings per diluted common share: Three months ended March 31, 2023 2022 Earnings per common share Net income $ 180,097 $ 149,200 Less: Preferred share dividends 7,563 7,563 Net income available to common shareholders $ 172,534 $ 141,637 Weighted average common shares outstanding 84,864 84,961 Earnings per common share $ 2.03 $ 1.67 Earnings per diluted common share Net income available to common shareholders $ 172,534 $ 141,637 Weighted average common shares outstanding 84,864 84,961 Share-based compensation plans 989 847 Weighted average diluted common shares outstanding 85,853 85,808 Earnings per diluted common share $ 2.01 $ 1.65 Weighted average anti-dilutive shares excluded from the dilutive computation 805 989

SHARE-BASED COMPENSATION

SHARE-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2023
Share-Based Payment Arrangement [Abstract]
SHARE-BASED COMPENSATION	Performance Restricted Stock Units Performance Restricted Stock Units granted in 2023 Share-settled performance restricted stock units granted in 2023 include a market condition which is the Company’s total shareholder return relative to its peer group ("Relative TSR") over the performance period. Relative TSR is calculated in accordance with the terms of the applicable award agreement. If performance goals are achieved, these awards will cliff vest at the end of a three-year performance period within a range of 0% to 200% of target. Performance Restricted Stock Units granted in 2023 granted in relation to senior leadership transition Share-settled performance restricted stock units granted in 2023 to one senior leader include a market condition which is the Company’s total shareholder return relative to its peer group ("Relative TSR") over the performance period. Relative TSR is calculated in accordance with the terms of the applicable award agreement. If performance goals are achieved, fifty percent of these awards will vest at the end of a one-year performance period, and the remaining fifty percent of these awards will vest at the end of a three-year vest period within a range of 0% to 200% of target. Valuation assumptions The fair value of performance restricted stock units granted in 2023 was measured on the grant date using a Monte Carlo simulation model. The following table provides details of the significant inputs used in the Monte Carlo simulation model: Three months ended March 31, 2023 (1) 2023 (2) 2022 Expected volatility 36.24% 29.30% 33.44% Expected term (in years) 3.0 1.0 3.0 Expected dividend yield n/a n/a n/a Risk-free interest rate 3.79% 4.61% 1.26% (1) Performance restricted stock units granted in the ordinary course of business (2) Performance restricted stock units granted in relation to senior leadership transition Beginning share price: The beginning share price was based on the average closing share price over the 10 trading days preceding and including the start of the performance period. Ending share price: The ending share price was based on the average projected closing share price over the 10 trading days preceding and including the end of the performance period. Expected volatility: The expected volatility is estimated based on the Company's historical share price volatility. Expected term: Performance for awards granted in 2023 is generally measured from January 1, 2023 to December 31, 2025, with performance for awards granted to one senior leader in relation to the senior leadership transition being measured from January 1, 2023 to December 31, 2023. Performance for awards granted in 2022 is measured from January 1, 2022 to December 31, 2024. Expected dividend yield: The expected dividend yield is not applicable to the performance restricted stock units as dividends are paid at the end of the vesting period and do not affect the value of the performance restricted stock units. Risk-free interest rate: The risk-free rate is estimated based on the yield on a U.S. treasury zero-coupon bond issued with a remaining term equal to the vesting period of the performance restricted stock units. Compensation expense associated with performance restricted stock units granted in 2023 and 2022 is determined on the grant date based on the fair value calculated by the Monte Carlo simulation model, and is recognized on a straight-line basis over the requisite service period. During the three months ended March 31, 2023, the transition in our senior leadership resulted in a modification of the previously existing vesting terms of the outstanding restricted stock units and performance restricted stock units granted in 2022 and earlier of one senior leader, and a modification of the performance period of that leader's performance restricted stock units granted in 2022. The modifications did not result in an incremental compensation expense. Share-Settled Awards The following table provides an activity summary of the Company's share-settled restricted stock units for the three months ended March 31, 2023: Share-Settled Performance Share-Settled Service Number of restricted stock units Weighted Number of restricted stock units Weighted average Non-vested restricted stock units - beginning of period 330 $ 60.01 2,117 $ 53.16 Granted 91 72.14 750 58.05 Vested (72) 62.26 (705) 54.02 Forfeited — — (33) 53.67 Non-vested restricted stock units - end of period 349 $ 62.73 2,129 $ 54.59 Cash-Settled awards The following table provides an activity summary of the Company's cash-settled restricted stock units for the three months ended March 31, 2023: Cash-Settled Service Number of Non-vested restricted stock units - beginning of period 60 Granted — Vested (59) Forfeited (1) Non-vested restricted stock units - end of period — The following table provides additional information related to share-based compensation: Three months ended March 31, 2023 2022 Share-based compensation expense (1) $ 12,526 $ 15,011 Tax benefits associated with share-based compensation expense $ 2,647 $ 2,426 Liability for cash-settled restricted stock units (2) $ — $ 3,023 Fair value of restricted stock units vested (3) $ 50,714 $ 46,970 Unrecognized share-based compensation expense $ 108,882 $ 125,964 Expected weighted average period associated with the recognition of unrecognized share-based compensation expense 2.8 years 2.9 years (1) Related to share-settled restricted stock units and cash-settled restricted stock units. (2) Included in other liabilities in the consolidated balance sheets. (3) Fair value is based on the closing price of the Company's common shares on the vest date.

SHAREHOLDERS' EQUITY

SHAREHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2023
Equity [Abstract]
SHAREHOLDERS' EQUITY	The following table presents changes in common shares issued and outstanding: Three months ended March 31, 2023 2022 Shares issued, balance at beginning of period 176,580 176,580 Shares issued — — Total shares issued at end of period 176,580 176,580 Treasury shares, balance at beginning of period (91,912) (91,806) Shares repurchased (262) (245) Shares reissued 777 747 Total treasury shares at end of period (91,397) (91,304) Total shares outstanding 85,183 85,276 Treasury Shares The following table presents common shares repurchased from shares held in Treasury: Three months ended March 31, 2023 2022 In the open market: Total shares — — Total cost $ — $ — Average price per share (1) $ — $ — From employees: (2) Total shares 262 245 Total cost $ 15,945 $ 12,977 Average price per share (1) $ 60.82 $ 52.93 Total shares repurchased: Total shares 262 245 Total cost $ 15,945 $ 12,977 Average price per share (1) $ 60.82 $ 52.93 (1) Calculated using whole numbers. (2) Shares are repurchased from employees to facilitate the satisfaction of their personal withholding tax liabilities that arise on the vesting of share-settled restricted stock units. Dividends The following table presents dividends declared and paid related to the Company's common and preferred shares: Per share data Dividends declared Dividends paid in period of declaration Dividends paid in period following declaration Three months ended March 31, 2023 Common shares $ 0.44 $ — $ 0.44 Series E preferred shares $ 34.38 $ — $ 34.38 Three months ended March 31, 2022 Common shares $ 0.43 $ — $ 0.43 Series E preferred shares $ 34.38 $ — $ 34.38

DEBT AND FINANCING ARRANGEMENTS

DEBT AND FINANCING ARRANGEMENTS	3 Months Ended
	Mar. 31, 2023
Debt Disclosure [Abstract]
DEBT AND FINANCING ARRANGEMENTS	Letter of Credit FacilityOn March 31, 2023, the $150 million secured letter of credit facility expired. The terms and conditions of the $500 million secured letter of credit facility remain unchanged.

FEDERAL HOME LOAN BANK ADVANCES

FEDERAL HOME LOAN BANK ADVANCES	3 Months Ended
	Mar. 31, 2023
Debt Disclosure [Abstract]
FEDERAL HOME LOAN BANK ADVANCES	The Company's subsidiaries, AXIS Insurance Company and AXIS Surplus Insurance Company are members of the Federal Home Loan Bank of Chicago ("FHLB"). At March 31, 2023, the companies had admitted assets of approximately $3 billion which provides borrowing capacity of up to approximately $750 million.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	Legal Proceedings From time to time, the Company is subject to routine legal proceedings, including arbitrations, arising in the ordinary course of business. These legal proceedings generally relate to claims asserted by or against the Company in the ordinary course of its insurance or reinsurance operations. Estimated amounts payable related to these proceedings are included in the reserve for losses and loss expenses in the Company's financial statements. The Company is not party to any material legal proceedings arising outside the ordinary course of business. Investments Refer to Note 3 - 'Investments' for information on the Company's unfunded investment commitments related to the Company's other investment portfolio.

OTHER COMPREHENSIVE INCOME (LOS

OTHER COMPREHENSIVE INCOME (LOSS)	3 Months Ended
	Mar. 31, 2023
Equity [Abstract]
OTHER COMPREHENSIVE INCOME (LOSS)	The following table presents the tax effects allocated to each component of other comprehensive income (loss): 2023 2022 Before tax amount Income tax (expense) benefit Net of tax amount Before tax amount Income tax (expense) benefit Net of Tax Amount Three months ended March 31, Available for sale investments: Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has not been recognized $ 153,851 $ (19,284) $ 134,567 $ (507,969) $ 65,247 $ (442,722) Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has been recognized 14,950 (1,328) 13,622 (232) — (232) Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss) 44,121 (3,371) 40,750 52,916 (7,573) 45,343 Unrealized gains (losses) arising during the period, net of reclassification adjustment 212,922 (23,983) 188,939 (455,285) 57,674 (397,611) Foreign currency translation adjustment (535) — (535) 2,775 — 2,775 Total comprehensive income (loss), net of tax $ 212,387 $ (23,983) $ 188,404 $ (452,510) $ 57,674 $ (394,836) The following table presents details of amounts reclassified from accumulated other comprehensive income ("AOCI") to net income (loss): Amount reclassified from AOCI (1) AOCI Components Consolidated statement of operations line item that includes reclassification adjustment Three months ended March 31, 2023 2022 Unrealized gains (losses) on available for sale investments Other realized gains (losses) $ (44,121) $ (52,807) Impairment losses — (109) Total before tax (44,121) (52,916) Income tax (expense) benefit 3,371 7,573 Net of tax $ (40,750) $ (45,343) (1) Amounts in parentheses are charges to net income (loss).

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	3 Months Ended
	Mar. 31, 2023
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	At March 31, 2023, the Company has invested $7 million in a loan to Eagle Point Credit Management LLC, which is majority-owned by Trident IX L.P., a Stone Point private equity fund.

BASIS OF PRESENTATION AND SIG_2

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	These unaudited consolidated financial statements (the "financial statements") have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the U.S. Securities and Exchange Commission's ("SEC") instructions to Form 10-Q and Article 10 of Regulation S-X and include AXIS Capital Holdings Limited ("AXIS Capital") and its subsidiaries (the "Company"). Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. This Quarterly Report on Form 10-Q should be read in conjunction with the financial statements and related notes included in AXIS Capital's Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the SEC. In the opinion of management, these financial statements reflect all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation of the Company's financial position and results of operations for the periods presented. The results of operations for any interim period are not necessarily indicative of the results for a full year. All inter-company accounts and transactions have been eliminated.

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	3 Months Ended
	Mar. 31, 2023
Segment Reporting [Abstract]
UNDERWRITING RESULTS OF REPORTABLE SEGMENTS	The following tables present the underwriting results of the Company's reportable segments, as well as the carrying amounts of allocated goodwill and intangible assets: 2023 2022 Three months ended and at March 31, Insurance Reinsurance Total Insurance Reinsurance Total Gross premiums written $ 1,415,612 $ 966,364 $ 2,381,976 $ 1,327,264 $ 1,307,344 $ 2,634,608 Net premiums written 882,576 725,780 1,608,356 843,912 968,960 1,812,872 Net premiums earned 816,456 413,743 1,230,199 752,816 505,430 1,258,246 Other insurance related income 54 523 577 82 6,611 6,693 Net losses and loss expenses (449,467) (271,175) (720,642) (405,745) (326,954) (732,699) Acquisition costs (147,058) (83,315) (230,373) (138,812) (109,540) (248,352) Underwriting-related general and administrative expenses (116,630) (23,765) (140,395) (113,950) (31,146) (145,096) Underwriting income $ 103,355 $ 36,011 139,366 $ 94,391 $ 44,401 138,792 Net investment income 133,771 91,355 Net investment losses (20,190) (94,508) Corporate expenses (26,416) (23,945) Foreign exchange (losses) gains (8,710) 44,273 Interest expense and financing costs (16,894) (15,564) Amortization of intangible assets (2,729) (2,729) Income before income taxes and interest in income (loss) of equity method investments 198,198 137,674 Income tax expense (15,896) (24) Interest in income (loss) of equity method investments (2,205) 11,550 Net income 180,097 149,200 Preferred share dividends 7,563 7,563 Net income available to common shareholders $ 172,534 $ 141,637 Net losses and loss expenses ratio 55.1 % 65.5 % 58.6 % 53.9 % 64.7 % 58.2 % Acquisition cost ratio 18.0 % 20.1 % 18.7 % 18.4 % 21.7 % 19.7 % General and administrative expense ratio 14.2 % 5.8 % 13.6 % 15.2 % 6.1 % 13.5 % Combined ratio 87.3 % 91.4 % 90.9 % 87.5 % 92.5 % 91.4 % Goodwill and intangible assets $ 295,872 $ — $ 295,872 $ 306,789 $ — $ 306,789

INVESTMENTS (Tables)

INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract]
AMORTIZED COST AND FAIR VALUES OF FIXED MATURITIES AVAILABLE FOR SALE	The following table provides the amortized cost and fair values of the Company's fixed maturities classified as available for sale: Amortized cost Allowance for expected credit losses Gross Gross unrealized losses Fair value At March 31, 2023 Available for sale U.S. government and agency $ 2,956,074 $ — $ 15,733 $ (70,495) $ 2,901,312 Non-U.S. government 587,923 (28) 3,511 (33,329) 558,077 Corporate debt 4,619,198 (12,436) 12,264 (321,814) 4,297,212 Agency RMBS (1) 1,344,187 — 9,111 (81,137) 1,272,161 CMBS (2) 996,699 — 165 (73,361) 923,503 Non-agency RMBS 145,288 (98) 134 (15,839) 129,485 ABS (3) 1,454,488 (36) 828 (57,897) 1,397,383 Municipals (4) 160,641 (47) 317 (12,489) 148,422 Total fixed maturities, available for sale $ 12,264,498 $ (12,645) $ 42,063 $ (666,361) $ 11,627,555 At December 31, 2022 Available for sale U.S. government and agency $ 2,731,733 $ — $ 5,386 $ (97,789) $ 2,639,330 Non-U.S. government 612,546 — 2,395 (52,912) 562,029 Corporate debt 4,680,798 (11,521) 5,269 (418,990) 4,255,556 Agency RMBS (1) 1,297,423 — 4,663 (99,301) 1,202,785 CMBS (2) 1,029,863 — 60 (82,145) 947,778 Non-agency RMBS 151,907 (123) 275 (18,525) 133,534 ABS (3) 1,499,728 (35) 555 (70,721) 1,429,527 Municipals (4) 172,475 (54) 139 (16,205) 156,355 Total fixed maturities, available for sale $ 12,176,473 $ (11,733) $ 18,742 $ (856,588) $ 11,326,894 (1) Residential mortgage-backed securities ("RMBS") originated by U.S. government-sponsored agencies. (2) Commercial mortgage-backed securities ("CMBS"). (3) Asset-backed securities ("ABS") include debt tranched securities collateralized primarily by auto loans, student loans, credit card receivables and collateralized loan obligations ("CLOs"). (4) Municipals include bonds issued by states, municipalities and political subdivisions.
CONTRACTUAL MATURITIES OF FIXED MATURITIES	The table below provides the contractual maturities of fixed maturities classified as available for sale: Amortized cost Fair value % of Total fair value At March 31, 2023 Maturity Due in one year or less $ 576,989 $ 563,123 4.9 % Due after one year through five years 5,400,687 5,204,250 44.8 % Due after five years through ten years 2,171,234 1,974,369 17.0 % Due after ten years 174,926 163,281 1.4 % 8,323,836 7,905,023 68.1 % Agency RMBS 1,344,187 1,272,161 10.9 % CMBS 996,699 923,503 7.9 % Non-agency RMBS 145,288 129,485 1.1 % ABS 1,454,488 1,397,383 12.0 % Total $ 12,264,498 $ 11,627,555 100.0 % At December 31, 2022 Maturity Due in one year or less $ 422,039 $ 409,972 3.7 % Due after one year through five years 5,349,123 5,078,273 44.8 % Due after five years through ten years 2,192,344 1,919,450 16.9 % Due after ten years 234,046 205,575 1.8 % 8,197,552 7,613,270 67.2 % Agency RMBS 1,297,423 1,202,785 10.6 % CMBS 1,029,863 947,778 8.4 % Non-agency RMBS 151,907 133,534 1.2 % ABS 1,499,728 1,429,527 12.6 % Total $ 12,176,473 $ 11,326,894 100.0 %
FIXED MATURITIES AVAILABLE FOR SALE IN AN UNREALIZED LOSS POSITION	The following table summarizes fixed maturities, available for sale in an unrealized loss position and the aggregate fair value and gross unrealized loss by length of time the security has continuously been in an unrealized loss position: 12 months or greater Less than 12 months Total Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses At March 31, 2023 Fixed maturities, available for sale U.S. government and agency $ 808,593 $ (51,696) $ 738,852 $ (18,799) $ 1,547,445 $ (70,495) Non-U.S. government 263,740 (31,114) 109,543 (2,215) 373,283 (33,329) Corporate debt 2,499,437 (287,339) 1,166,503 (34,475) 3,665,940 (321,814) Agency RMBS 533,145 (64,620) 433,607 (16,517) 966,752 (81,137) CMBS 764,365 (66,063) 140,843 (7,298) 905,208 (73,361) Non-agency RMBS 99,758 (15,383) 23,591 (456) 123,349 (15,839) ABS 1,179,697 (56,118) 134,693 (1,779) 1,314,390 (57,897) Municipals 105,115 (11,526) 31,816 (963) 136,931 (12,489) Total fixed maturities, available for sale $ 6,253,850 $ (583,859) $ 2,779,448 $ (82,502) $ 9,033,298 $ (666,361) At December 31, 2022 Fixed maturities, available for sale U.S. government and agency $ 467,032 $ (41,365) $ 1,414,181 $ (56,424) $ 1,881,213 $ (97,789) Non-U.S. government 207,637 (33,027) 298,048 (19,885) 505,685 (52,912) Corporate debt 1,562,355 (268,289) 2,350,504 (150,701) 3,912,859 (418,990) Agency RMBS 220,595 (40,469) 771,191 (58,832) 991,786 (99,301) CMBS 343,494 (40,888) 599,877 (41,257) 943,371 (82,145) Non-agency RMBS 75,137 (14,691) 53,484 (3,834) 128,621 (18,525) ABS 685,990 (48,913) 686,190 (21,808) 1,372,180 (70,721) Municipals 52,994 (10,120) 96,003 (6,085) 148,997 (16,205) Total fixed maturities, available for sale $ 3,615,234 $ (497,762) $ 6,269,478 $ (358,826) $ 9,884,712 $ (856,588)
FIXED MATURITIES, HELD-TO-MATURITY	The following table provides the amortized cost and fair values of the Company's fixed maturities classified as held to maturity: Amortized cost Allowance for expected credit losses Net carrying value Gross Gross unrealized losses Fair value At March 31, 2023 Held to maturity Corporate debt $ 85,200 $ — $ 85,200 $ — $ (9,535) $ 75,665 ABS (1) 631,568 — 631,568 — (10,458) 621,110 Total fixed maturities, held to maturity $ 716,768 $ — $ 716,768 $ — $ (19,993) $ 696,775 At December 31, 2022 Held to maturity Corporate debt $ 85,200 $ — $ 85,200 $ — $ (11,428) $ 73,772 ABS (1) 613,151 — 613,151 — (12,180) 600,971 Total fixed maturities, held to maturity $ 698,351 $ — $ 698,351 $ — $ (23,608) $ 674,743 (1) Asset-backed securities ("ABS") include debt tranched securities collateralized primarily by collateralized loan obligations ("CLOs").
EQUITY SECURITIES	The following table provides the cost and fair values of the Company's equity securities: Cost Gross unrealized gains Gross unrealized losses Fair value At March 31, 2023 Equity securities Common stocks $ 3,130 $ 321 $ (437) $ 3,014 Preferred stocks 115 — (113) 2 Exchange-traded funds 199,212 83,523 (3,016) 279,719 Bond mutual funds 356,836 50 (65,705) 291,181 Total equity securities $ 559,293 $ 83,894 $ (69,271) $ 573,916 At December 31, 2022 Equity securities Common stocks $ 7,279 $ 636 $ (442) $ 7,473 Preferred stocks 115 — (43) 72 Exchange-traded funds 207,505 68,058 (5,757) 269,806 Bond mutual funds 279,457 — (71,555) 207,902 Total equity securities $ 494,356 $ 68,694 $ (77,797) $ 485,253
MORTGAGE LOANS NET OF VALUATION ALLOWANCE	The following table provides details of the Company's mortgage loans, held for investment: March 31, 2023 December 31, 2022 Carrying value % of Total Carrying value % of Total Mortgage loans, held for investment: Commercial $ 636,370 100 % $ 627,437 100 % Allowance for expected credit losses (1,900) — % — — % Total mortgage loans, held for investment $ 634,470 100 % $ 627,437 100 %
PORTFOLIO OF OTHER INVESTMENTS	The following table provides a summary of the Company's other investments, together with additional information relating to the liquidity of each category: Fair value % of Total Redemption frequency (if currently eligible) Redemption notice period At March 31, 2023 Multi-strategy funds $ 30,721 3 % Quarterly 60-90 days Direct lending funds 258,183 26 % Quarterly (1) 90 days Private equity funds 273,859 27 % n/a n/a Real estate funds 300,152 30 % Quarterly (2) , Annually (3) 45-90 days CLO-Equities 5,019 — % n/a n/a Other privately held investments 140,953 14 % n/a n/a Total other investments $ 1,008,887 100 % At December 31, 2022 Multi-strategy funds $ 32,616 3 % Quarterly 60-90 days Direct lending funds 258,626 26 % Quarterly (1) 90 days Private equity funds 265,836 27 % n/a n/a Real estate funds 298,499 30 % Quarterly (2) , Annually (3) 45-90 days CLO-Equities 5,016 — % n/a n/a Other privately held investments 136,158 14 % n/a n/a Total other investments $ 996,751 100 % n/a - not applicable (1) Applies to one fund with a fair va lue of $35 million (2022: $39 million). (2) Applies to one fund with a fair value of $72 million (2022: $73 million ). (3) Applies to one fund with a fair value of $25 million (2022: $27 million ).
NET INVESTMENT INCOME	Net investment income was derived from the following sources: Three months ended March 31, 2023 2022 Fixed maturities $ 118,262 $ 64,809 Other investments 486 26,050 Equity securities 2,455 2,172 Mortgage loans 8,386 4,163 Cash and cash equivalents 10,012 1,118 Short-term investments 1,660 166 Gross investment income 141,261 98,478 Investment expenses (7,490) (7,123) Net investment income $ 133,771 $ 91,355
NET INVESTMENT GAINS (LOSSES)	The following table provides an analysis of net investment gains (losses): Three months ended March 31, 2023 2022 Gross realized investment gains Fixed maturities and short-term investments $ 12,370 $ 10,422 Equity securities 1,517 — Gross realized investment gains 13,887 10,422 Gross realized investment losses Fixed maturities and short-term investments (53,649) (63,146) Equity securities (396) (225) Gross realized investment losses (54,045) (63,371) (Increase) decrease in allowance for expected credit losses, fixed maturities, available for sale (911) (70) (Increase) decrease in allowance for expected credit losses, mortgage loans (1,900) — Impairment losses (1) — (109) Change in fair value of investment derivatives (2) (947) 2,242 Net unrealized gains (losses) on equity securities 23,726 (43,622) Net investment losses $ (20,190) $ (94,508) (1) Related to instances where the Company intends to sell securities or it is more likely than not that the Company will be required to sell securities before their anticipated recovery. (2) Refer to Note 5 ' Derivative Instruments'.
ALLOWANCE FOR EXPECTED CREDIT LOSSES ON FIXED MATURITIES AVAILABLE FOR SALE	The following table provides a reconciliation of the beginning and ending balances of the allowance for expected credit losses on fixed maturities classified as available for sale: Three months ended March 31, 2023 2022 Balance at beginning of period $ 11,733 $ 313 Expected credit losses on securities where credit losses were not previously recognized 613 9 Additions (reductions) for expected credit losses on securities where credit losses were previously recognized 919 78 Impairments of securities which the Company intends to sell or more likely than not will be required to sell — — Securities sold/redeemed/matured (620) (17) Balance at end of period $ 12,645 $ 383

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2023
Fair Value Disclosures [Abstract]
FINANCIAL INSTRUMENTS MEASURED AT FAIR VALUE ON A RECURRING BASIS	The tables below present the financial instruments measured at fair value on a recurring basis for the periods indicated: Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Fair value based on NAV practical expedient Total fair value At March 31, 2023 Assets Fixed maturities, available for sale U.S. government and agency $ 2,862,087 $ 39,225 $ — $ — $ 2,901,312 Non-U.S. government — 558,077 — — 558,077 Corporate debt — 4,166,785 130,427 — 4,297,212 Agency RMBS — 1,272,161 — — 1,272,161 CMBS — 923,503 — — 923,503 Non-agency RMBS — 129,485 — — 129,485 ABS — 1,397,383 — — 1,397,383 Municipals — 148,422 — — 148,422 2,862,087 8,635,041 130,427 — 11,627,555 Equity securities Common stocks 3,014 — — — 3,014 Preferred stocks 2 — — — 2 Exchange-traded funds 279,719 — — — 279,719 Bond mutual funds — 291,181 — — 291,181 282,735 291,181 — — 573,916 Other investments Multi-strategy funds — — — 30,721 30,721 Direct lending funds — — — 258,183 258,183 Private equity funds — — — 273,859 273,859 Real estate funds — — — 300,152 300,152 CLO-Equities — — 5,019 — 5,019 Other privately held investments — — 140,953 — 140,953 — — 145,972 862,915 1,008,887 Short-term investments — 70,416 — — 70,416 Other assets Derivative instruments (refer to Note 5) — 7,752 — — 7,752 Total Assets $ 3,144,822 $ 9,004,390 $ 276,399 $ 862,915 $ 13,288,526 Liabilities Derivative instruments (refer to Note 5) $ — $ 2,789 $ — $ — $ 2,789 Cash-settled awards (refer to Note 8) — — — — — Total Liabilities $ — $ 2,789 $ — $ — $ 2,789 Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Fair value based on NAV practical expedient Total fair value At December 31, 2022 Assets Fixed maturities, available for sale U.S. government and agency $ 2,600,636 $ 38,694 $ — $ — $ 2,639,330 Non-U.S. government — 562,029 — — 562,029 Corporate debt — 4,136,452 119,104 — 4,255,556 Agency RMBS — 1,202,785 — — 1,202,785 CMBS — 947,778 — — 947,778 Non-agency RMBS — 133,534 — — 133,534 ABS — 1,429,527 — — 1,429,527 Municipals — 156,355 — — 156,355 2,600,636 8,607,154 119,104 — 11,326,894 Equity securities Common stocks 7,473 — — — 7,473 Preferred stocks 72 — — — 72 Exchange-traded funds 269,806 — — — 269,806 Bond mutual funds — 207,902 — — 207,902 277,351 207,902 — — 485,253 Other investments Multi-strategy funds — — — 32,616 32,616 Direct lending funds — — — 258,626 258,626 Private equity funds — — — 265,836 265,836 Real estate funds — — — 298,499 298,499 CLO-Equities — — 5,016 — 5,016 Other privately held investments — — 136,158 — 136,158 — — 141,174 855,577 996,751 Short-term investments — 70,310 — — 70,310 Other assets Derivative instruments (refer to Note 5) — 37,682 — — 37,682 Total Assets $ 2,877,987 $ 8,923,048 $ 260,278 $ 855,577 $ 12,916,890 Liabilities Derivative instruments (refer to Note 5) $ — $ 703 $ — $ — $ 703 Cash-settled awards (refer to Note 8) — 4,792 — — 4,792 Total Liabilities $ — $ 5,495 $ — $ — $ 5,495
LEVEL 3 FAIR VALUE MEASUREMENT INPUTS	The following table quantifies the significant unobservable inputs used in estimating fair values at March 31, 2023 of investments classified as Level 3 in the fair value hierarchy: Asset fair value Valuation technique Unobservable input Amount / Range Weighted average Other investments - CLO-Equities $ 5,019 Discounted cash flow Default rate 4.5% 4.5% Loss severity rate 50.0% 50.0% Collateral spread 3.0% 3.0% Estimated maturity date 5 years 5 years Other investments - Other privately held investments $ 17,522 Discounted cash flow Discount rate 6.6% 6.6% Default rate 0.5% 0.5% Loss absorption yield 1.0% 1.0% Estimated maturity date 1-3 years 2 years Note: Fixed maturities of $130 million that are classified as Level 3 are excluded from the above table as these securities are priced using broker-dealer quotes. In addition, other privately held investments of $123 million that are classified as Level 3 are excluded from the above table as these investments are priced using capital statements received from investee companies.
CHANGES IN LEVEL 3 FINANCIAL INSTRUMENTS MEASURED AT FAIR VALUE ON A RECURRING BASIS, ASSETS	The following table presents changes in Level 3 for financial instruments measured at fair value on a recurring basis: Opening balance Transfers into Level 3 Transfers out of Level 3 Included in net income (1) Included in OCI (2) Purchases Sales Settlements/ distributions Closing balance Change in unrealized gains/(losses) (3) Three months ended March 31, 2023 Fixed maturities, available for sale Corporate debt $ 119,104 $ — $ — $ (7) $ 1,183 $ 18,910 $ — $ (8,763) $ 130,427 $ — 119,104 — — (7) 1,183 18,910 — (8,763) 130,427 — Other investments CLO-Equities 5,016 — — 411 — — — (408) 5,019 411 Other privately held investments 136,158 — — 336 — 4,459 — — 140,953 336 141,174 — — 747 — 4,459 — (408) 145,972 747 Total assets $ 260,278 $ — $ — $ 740 $ 1,183 $ 23,369 $ — $ (9,171) $ 276,399 $ 747 Other liabilities Derivative instruments $ — $ — $ — $ — $ — $ — $ — $ — $ — $ — Total liabilities $ — $ — $ — $ — $ — $ — $ — $ — $ — $ — Three months ended March 31, 2022 Fixed maturities, available for sale Corporate debt $ 42,894 $ — $ — $ — $ (2,794) $ 21,462 $ — $ (672) $ 60,890 $ — 42,894 — — — (2,794) 21,462 — (672) 60,890 — Other investments CLO-Equities 5,910 — — 872 — — — (1,901) 4,881 872 Other privately held investments 104,521 — — 1,618 — 9,335 — — 115,474 1,618 110,431 — — 2,490 — 9,335 — (1,901) 120,355 2,490 Total assets $ 153,325 $ — $ — $ 2,490 $ (2,794) $ 30,797 $ — $ (2,573) $ 181,245 $ 2,490 Other liabilities Derivative instruments $ 5,630 $ — $ — $ (556) $ — $ — $ — $ — $ 5,074 $ (556) Total liabilities $ 5,630 $ — $ — $ (556) $ — $ — $ — $ — $ 5,074 $ (556) (1) Realized gains (losses) on fixed maturities and realized and unrealized gains (losses) on other assets and other liabilities included in net income are included in net investment gains (losses). Realized and unrealized gains (losses) on other investments included in net income are included in net investment income. (2) Unrealized gains (losses) on fixed maturities are included in other comprehensive income ("OCI"). (3) Change in unrealized gains (losses) relating to assets and liabilities held at the reporting date.
CHANGES IN LEVEL 3 FINANCIAL INSTRUMENTS MEASURED AT FAIR VALUE ON A RECURRING BASIS, LIABILITIES	The following table presents changes in Level 3 for financial instruments measured at fair value on a recurring basis: Opening balance Transfers into Level 3 Transfers out of Level 3 Included in net income (1) Included in OCI (2) Purchases Sales Settlements/ distributions Closing balance Change in unrealized gains/(losses) (3) Three months ended March 31, 2023 Fixed maturities, available for sale Corporate debt $ 119,104 $ — $ — $ (7) $ 1,183 $ 18,910 $ — $ (8,763) $ 130,427 $ — 119,104 — — (7) 1,183 18,910 — (8,763) 130,427 — Other investments CLO-Equities 5,016 — — 411 — — — (408) 5,019 411 Other privately held investments 136,158 — — 336 — 4,459 — — 140,953 336 141,174 — — 747 — 4,459 — (408) 145,972 747 Total assets $ 260,278 $ — $ — $ 740 $ 1,183 $ 23,369 $ — $ (9,171) $ 276,399 $ 747 Other liabilities Derivative instruments $ — $ — $ — $ — $ — $ — $ — $ — $ — $ — Total liabilities $ — $ — $ — $ — $ — $ — $ — $ — $ — $ — Three months ended March 31, 2022 Fixed maturities, available for sale Corporate debt $ 42,894 $ — $ — $ — $ (2,794) $ 21,462 $ — $ (672) $ 60,890 $ — 42,894 — — — (2,794) 21,462 — (672) 60,890 — Other investments CLO-Equities 5,910 — — 872 — — — (1,901) 4,881 872 Other privately held investments 104,521 — — 1,618 — 9,335 — — 115,474 1,618 110,431 — — 2,490 — 9,335 — (1,901) 120,355 2,490 Total assets $ 153,325 $ — $ — $ 2,490 $ (2,794) $ 30,797 $ — $ (2,573) $ 181,245 $ 2,490 Other liabilities Derivative instruments $ 5,630 $ — $ — $ (556) $ — $ — $ — $ — $ 5,074 $ (556) Total liabilities $ 5,630 $ — $ — $ (556) $ — $ — $ — $ — $ 5,074 $ (556) (1) Realized gains (losses) on fixed maturities and realized and unrealized gains (losses) on other assets and other liabilities included in net income are included in net investment gains (losses). Realized and unrealized gains (losses) on other investments included in net income are included in net investment income. (2) Unrealized gains (losses) on fixed maturities are included in other comprehensive income ("OCI"). (3) Change in unrealized gains (losses) relating to assets and liabilities held at the reporting date.

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
LOCATION AND AMOUNTS OF DERIVATIVE FAIR VALUES ON THE CONSOLIDATED BALANCE SHEET	The following table provides the balance sheet classifications of derivatives recorded at fair value: March 31, 2023 December 31, 2022 Derivative notional amount Derivative asset fair value (1) Derivative liability fair value (1) Derivative notional amount Derivative asset fair value (1) Derivative liability fair value (1) Relating to investment portfolio: Foreign exchange forward contracts $ 51,959 $ — $ 1,244 $ 54,076 $ 81 $ 559 Relating to underwriting portfolio: Foreign exchange forward contracts 1,318,403 7,752 1,545 1,441,273 37,601 144 Total derivatives $ 7,752 $ 2,789 $ 37,682 $ 703 (1) Derivative assets and derivative liabilities are classified within other assets and other liabilities in the consolidated balance sheets.
RECONCILIATION OF GROSS DERIVATIVE ASSETS TO NET AMOUNTS PRESENTED IN BALANCE SHEETS	The following table provides a reconciliation of gross derivative assets and liabilities to the net amounts presented in the consolidated balance sheets, with the difference being attributable to the impact of master netting agreements: March 31, 2023 December 31, 2022 Gross amounts Gross amounts offset Net amounts (1) Gross amounts Gross amounts offset Net amounts (1) Derivative assets $ 11,632 $ (3,880) $ 7,752 $ 41,762 $ (4,080) $ 37,682 Derivative liabilities $ 6,669 $ (3,880) $ 2,789 $ 4,783 $ (4,080) $ 703 (1) Net asset and liability derivatives are classified within other assets and other liabilities in the consolidated balance sheets.
RECONCILIATION OF GROSS DERIVATIVE LIABILITIES TO NET AMOUNTS PRESENTED IN BALANCE SHEETS	The following table provides a reconciliation of gross derivative assets and liabilities to the net amounts presented in the consolidated balance sheets, with the difference being attributable to the impact of master netting agreements: March 31, 2023 December 31, 2022 Gross amounts Gross amounts offset Net amounts (1) Gross amounts Gross amounts offset Net amounts (1) Derivative assets $ 11,632 $ (3,880) $ 7,752 $ 41,762 $ (4,080) $ 37,682 Derivative liabilities $ 6,669 $ (3,880) $ 2,789 $ 4,783 $ (4,080) $ 703 (1) Net asset and liability derivatives are classified within other assets and other liabilities in the consolidated balance sheets.
TOTAL UNREALIZED AND REALIZED GAINS (LOSSES) ON DERIVATIVES NOT DESIGNATED AS HEDGES RECORDED IN EARNINGS	The following table provides the total unrealized and realized gains (losses) recognized in net income (loss) for derivatives not designated as hedges: Consolidated statement of operations line item that includes gain (loss) recognized in net income (loss) Three months ended March 31, 2023 2022 Relating to investment portfolio: Foreign exchange forward contracts Net investment gains (losses) $ (947) $ 2,242 Relating to underwriting portfolio: Foreign exchange forward contracts Foreign exchange (losses) gains 11,250 (27,976) Other underwriting-related contracts Other insurance related income (loss) — 555 Total $ 10,303 $ (25,179)

RESERVE FOR LOSSES AND LOSS E_2

RESERVE FOR LOSSES AND LOSS EXPENSES (Tables)	3 Months Ended
	Mar. 31, 2023
Insurance [Abstract]
RECONCILIATION OF BEGINNING AND ENDING GROSS RESERVE FOR LOSSES AND LOSS EXPENSES AND NET RESERVE FOR UNPAID LOSSES AND LOSS EXPENSES	The following table presents a reconciliation of the Company's beginning and ending gross reserve for losses and loss expenses and net reserve for unpaid losses and loss expenses: Three months ended March 31, 2023 2022 Gross reserve for losses and loss expenses, beginning of period $ 15,168,863 $ 14,653,094 Less reinsurance recoverable on unpaid losses and loss expenses, beginning of period (5,831,172) (5,017,611) Net reserve for unpaid losses and loss expenses, beginning of period 9,337,691 9,635,483 Net incurred losses and loss expenses related to: Current year 724,680 741,655 Prior years (4,038) (8,956) 720,642 732,699 Net paid losses and loss expenses related to: Current year (38,662) (32,477) Prior years (574,538) (750,969) (613,200) (783,446) Foreign exchange and other 46,094 (71,661) Net reserve for unpaid losses and loss expenses, end of period 9,491,227 9,513,075 Reinsurance recoverable on unpaid losses and loss expenses, end of period 5,823,417 4,957,080 Gross reserve for losses and loss expenses, end of period $ 15,314,644 $ 14,470,155
SCHEDULE OF THE LINE OF BUSINESS CATEGORIES AND THE EXPECTED CLAIM TAILS	The following table maps the Company's lines of business to expected claim tails: Insurance segment Expected claims tail Short Medium Long Lines of business Property X Accident and health X Marine and aviation X Cyber X Professional lines X Credit and political risk X Liability X The following table maps the Company's lines of business to expected claim tails: Reinsurance segment Expected claims tail Short Medium Long Lines of business Accident and health X Agriculture X Marine and aviation X Professional lines X Credit and surety X Motor X Liability X Run-off lines Catastrophe X Property X Engineering X
SCHEDULE OF PRIOR YEAR DEVELOPMENT BY SEGMENT AND LINE OF BUSINESS	The following table presents net prior year reserve development by segment: Net Favorable Prior Year Reserve Development Insurance Reinsurance Total Three months ended March 31, 2023 $ 1,041 $ 2,997 $ 4,038 Three months ended March 31, 2022 $ 7,062 $ 1,894 $ 8,956 Prior year reserve development by line of business was as follows: Three months ended March 31, 2023 2022 Favorable (Adverse) Favorable (Adverse) Property $ 5,900 $ 8,060 Accident and health (304) 3,632 Marine and aviation 13,221 14,647 Cyber 8,452 (687) Professional lines (12,594) (5,936) Credit and political risk 4,519 895 Liability (18,153) (13,549) Total $ 1,041 $ 7,062 Prior year reserve development by line of business was as follows: Three months ended March 31, 2023 2022 Favorable Favorable Accident and health $ 6,988 $ (499) Agriculture 11,891 1,231 Marine and aviation (250) 497 Professional lines (3,225) (24,522) Credit and surety (546) 7,465 Motor (17,122) (1,730) Liability (32,853) (4,105) Run-off lines Catastrophe 31,058 (246) Property 6,883 22,539 Engineering 173 1,264 Total run-off lines 38,114 23,557 Total $ 2,997 $ 1,894

EARNINGS PER COMMON SHARE (Tabl

EARNINGS PER COMMON SHARE (Tables)	3 Months Ended
	Mar. 31, 2023
Earnings Per Share [Abstract]
BASIC AND DILUTED EARNINGS PER COMMON SHARE	The following table presents a comparison of earnings per common share and earnings per diluted common share: Three months ended March 31, 2023 2022 Earnings per common share Net income $ 180,097 $ 149,200 Less: Preferred share dividends 7,563 7,563 Net income available to common shareholders $ 172,534 $ 141,637 Weighted average common shares outstanding 84,864 84,961 Earnings per common share $ 2.03 $ 1.67 Earnings per diluted common share Net income available to common shareholders $ 172,534 $ 141,637 Weighted average common shares outstanding 84,864 84,961 Share-based compensation plans 989 847 Weighted average diluted common shares outstanding 85,853 85,808 Earnings per diluted common share $ 2.01 $ 1.65 Weighted average anti-dilutive shares excluded from the dilutive computation 805 989

SHARE-BASED COMPENSATION (Table

SHARE-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2023
Share-Based Payment Arrangement [Abstract]
SUMMARY OF ADDITIONAL INFORMATION RELATED TO SHARE-BASED COMPENSATION	The following table provides details of the significant inputs used in the Monte Carlo simulation model: Three months ended March 31, 2023 (1) 2023 (2) 2022 Expected volatility 36.24% 29.30% 33.44% Expected term (in years) 3.0 1.0 3.0 Expected dividend yield n/a n/a n/a Risk-free interest rate 3.79% 4.61% 1.26% (1) Performance restricted stock units granted in the ordinary course of business (2) Performance restricted stock units granted in relation to senior leadership transition The following table provides additional information related to share-based compensation: Three months ended March 31, 2023 2022 Share-based compensation expense (1) $ 12,526 $ 15,011 Tax benefits associated with share-based compensation expense $ 2,647 $ 2,426 Liability for cash-settled restricted stock units (2) $ — $ 3,023 Fair value of restricted stock units vested (3) $ 50,714 $ 46,970 Unrecognized share-based compensation expense $ 108,882 $ 125,964 Expected weighted average period associated with the recognition of unrecognized share-based compensation expense 2.8 years 2.9 years (1) Related to share-settled restricted stock units and cash-settled restricted stock units. (2) Included in other liabilities in the consolidated balance sheets. (3) Fair value is based on the closing price of the Company's common shares on the vest date.
SUMMARY OF SHARE-SETTLED RESTRICTED STOCK UNITS	The following table provides an activity summary of the Company's share-settled restricted stock units for the three months ended March 31, 2023: Share-Settled Performance Share-Settled Service Number of restricted stock units Weighted Number of restricted stock units Weighted average Non-vested restricted stock units - beginning of period 330 $ 60.01 2,117 $ 53.16 Granted 91 72.14 750 58.05 Vested (72) 62.26 (705) 54.02 Forfeited — — (33) 53.67 Non-vested restricted stock units - end of period 349 $ 62.73 2,129 $ 54.59
SUMMARY OF CASH-SETTLED RESTRICTED STOCK UNITS	The following table provides an activity summary of the Company's cash-settled restricted stock units for the three months ended March 31, 2023: Cash-Settled Service Number of Non-vested restricted stock units - beginning of period 60 Granted — Vested (59) Forfeited (1) Non-vested restricted stock units - end of period —

SHAREHOLDERS' EQUITY (Tables)

SHAREHOLDERS' EQUITY (Tables)	3 Months Ended
	Mar. 31, 2023
Equity [Abstract]
COMMON SHARES ISSUED AND OUTSTANDING	The following table presents changes in common shares issued and outstanding: Three months ended March 31, 2023 2022 Shares issued, balance at beginning of period 176,580 176,580 Shares issued — — Total shares issued at end of period 176,580 176,580 Treasury shares, balance at beginning of period (91,912) (91,806) Shares repurchased (262) (245) Shares reissued 777 747 Total treasury shares at end of period (91,397) (91,304) Total shares outstanding 85,183 85,276
SHARE REPURCHASES	The following table presents common shares repurchased from shares held in Treasury: Three months ended March 31, 2023 2022 In the open market: Total shares — — Total cost $ — $ — Average price per share (1) $ — $ — From employees: (2) Total shares 262 245 Total cost $ 15,945 $ 12,977 Average price per share (1) $ 60.82 $ 52.93 Total shares repurchased: Total shares 262 245 Total cost $ 15,945 $ 12,977 Average price per share (1) $ 60.82 $ 52.93 (1) Calculated using whole numbers. (2) Shares are repurchased from employees to facilitate the satisfaction of their personal withholding tax liabilities that arise on the vesting of share-settled restricted stock units.
DIVIDENDS	The following table presents dividends declared and paid related to the Company's common and preferred shares: Per share data Dividends declared Dividends paid in period of declaration Dividends paid in period following declaration Three months ended March 31, 2023 Common shares $ 0.44 $ — $ 0.44 Series E preferred shares $ 34.38 $ — $ 34.38 Three months ended March 31, 2022 Common shares $ 0.43 $ — $ 0.43 Series E preferred shares $ 34.38 $ — $ 34.38

OTHER COMPREHENSIVE INCOME (L_2

OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	3 Months Ended
	Mar. 31, 2023
Equity [Abstract]
TAX EFFECTS ALLOCATED TO EACH COMPONENT OF OTHER COMPREHENSIVE INCOME	The following table presents the tax effects allocated to each component of other comprehensive income (loss): 2023 2022 Before tax amount Income tax (expense) benefit Net of tax amount Before tax amount Income tax (expense) benefit Net of Tax Amount Three months ended March 31, Available for sale investments: Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has not been recognized $ 153,851 $ (19,284) $ 134,567 $ (507,969) $ 65,247 $ (442,722) Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has been recognized 14,950 (1,328) 13,622 (232) — (232) Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss) 44,121 (3,371) 40,750 52,916 (7,573) 45,343 Unrealized gains (losses) arising during the period, net of reclassification adjustment 212,922 (23,983) 188,939 (455,285) 57,674 (397,611) Foreign currency translation adjustment (535) — (535) 2,775 — 2,775 Total comprehensive income (loss), net of tax $ 212,387 $ (23,983) $ 188,404 $ (452,510) $ 57,674 $ (394,836)
DETAILS OF AMOUNTS RECLASSIFIED FROM AOCI TO NET INCOME (LOSS)	The following table presents details of amounts reclassified from accumulated other comprehensive income ("AOCI") to net income (loss): Amount reclassified from AOCI (1) AOCI Components Consolidated statement of operations line item that includes reclassification adjustment Three months ended March 31, 2023 2022 Unrealized gains (losses) on available for sale investments Other realized gains (losses) $ (44,121) $ (52,807) Impairment losses — (109) Total before tax (44,121) (52,916) Income tax (expense) benefit 3,371 7,573 Net of tax $ (40,750) $ (45,343) (1) Amounts in parentheses are charges to net income (loss).

SEGMENT INFORMATION (Details)

SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($) segment	Mar. 31, 2022 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment	2
Segment Information [Line Items]
Net premiums earned	$ 1,230,199	$ 1,258,246
Other insurance related income	577	6,693
Net losses and loss expenses	(720,642)	(732,699)
Acquisition costs	(230,373)	(248,352)
Underwriting-related general and administrative expenses and corporate expenses	(166,811)	(169,041)
Net investment income	133,771	91,355
Foreign exchange (losses) gains	(8,710)	44,273
Interest expense and financing costs	(16,894)	(15,564)
Amortization of intangible assets	(2,729)	(2,729)
Income before income taxes and interest in income (loss) of equity method investments	198,198	137,674
Income tax expense	(15,896)	(24)
Interest in income (loss) of equity method investments	(2,205)	11,550
Net income	180,097	149,200
Preferred share dividends	7,563	7,563
Net income available to common shareholders	172,534	141,637
Operating Segments
Segment Information [Line Items]
Gross premiums written	2,381,976	2,634,608
Net premiums written	1,608,356	1,812,872
Net premiums earned	1,230,199	1,258,246
Other insurance related income	577	6,693
Net losses and loss expenses	(720,642)	(732,699)
Acquisition costs	(230,373)	(248,352)
Underwriting-related general and administrative expenses and corporate expenses	(140,395)	(145,096)
Underwriting income	$ 139,366	$ 138,792
Net losses and loss expenses ratio (as a percent)	58.60%	58.20%
Acquisition cost ratio (as a percent)	18.70%	19.70%
General and administrative expense ratio (as a percent)	13.60%	13.50%
Combined ratio (as a percent)	90.90%	91.40%
Goodwill and intangible assets	$ 295,872	$ 306,789
Operating Segments | Insurance
Segment Information [Line Items]
Gross premiums written	1,415,612	1,327,264
Net premiums written	882,576	843,912
Net premiums earned	816,456	752,816
Other insurance related income	54	82
Net losses and loss expenses	(449,467)	(405,745)
Acquisition costs	(147,058)	(138,812)
Underwriting-related general and administrative expenses and corporate expenses	(116,630)	(113,950)
Underwriting income	$ 103,355	$ 94,391
Net losses and loss expenses ratio (as a percent)	55.10%	53.90%
Acquisition cost ratio (as a percent)	18%	18.40%
General and administrative expense ratio (as a percent)	14.20%	15.20%
Combined ratio (as a percent)	87.30%	87.50%
Goodwill and intangible assets	$ 295,872	$ 306,789
Operating Segments | Reinsurance
Segment Information [Line Items]
Gross premiums written	966,364	1,307,344
Net premiums written	725,780	968,960
Net premiums earned	413,743	505,430
Other insurance related income	523	6,611
Net losses and loss expenses	(271,175)	(326,954)
Acquisition costs	(83,315)	(109,540)
Underwriting-related general and administrative expenses and corporate expenses	(23,765)	(31,146)
Underwriting income	$ 36,011	$ 44,401
Net losses and loss expenses ratio (as a percent)	65.50%	64.70%
Acquisition cost ratio (as a percent)	20.10%	21.70%
General and administrative expense ratio (as a percent)	5.80%	6.10%
Combined ratio (as a percent)	91.40%	92.50%
Goodwill and intangible assets	$ 0	$ 0
Segment Reconciling Items
Segment Information [Line Items]
Net investment income	133,771	91,355
Net investment losses	(20,190)	(94,508)
Foreign exchange (losses) gains	(8,710)	44,273
Interest expense and financing costs	(16,894)	(15,564)
Amortization of intangible assets	(2,729)	(2,729)
Corporate Expenses
Segment Information [Line Items]
Underwriting-related general and administrative expenses and corporate expenses	$ (26,416)	$ (23,945)

INVESTMENTS - Fixed Maturities

INVESTMENTS - Fixed Maturities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Available for sale
Amortized cost	$ 12,264,498	$ 12,176,473
Allowance for expected credit losses	(12,645)	(11,733)	$ (383)	$ (313)
Gross unrealized gains	42,063	18,742
Gross unrealized losses	(666,361)	(856,588)
Fair value	11,627,555	11,326,894
U.S. government and agency
Available for sale
Amortized cost	2,956,074	2,731,733
Allowance for expected credit losses	0	0
Gross unrealized gains	15,733	5,386
Gross unrealized losses	(70,495)	(97,789)
Fair value	2,901,312	2,639,330
Non-U.S. government
Available for sale
Amortized cost	587,923	612,546
Allowance for expected credit losses	(28)	0
Gross unrealized gains	3,511	2,395
Gross unrealized losses	(33,329)	(52,912)
Fair value	558,077	562,029
Corporate debt
Available for sale
Amortized cost	4,619,198	4,680,798
Allowance for expected credit losses	(12,436)	(11,521)
Gross unrealized gains	12,264	5,269
Gross unrealized losses	(321,814)	(418,990)
Fair value	4,297,212	4,255,556
Agency RMBS
Available for sale
Amortized cost	1,344,187	1,297,423
Allowance for expected credit losses	0	0
Gross unrealized gains	9,111	4,663
Gross unrealized losses	(81,137)	(99,301)
Fair value	1,272,161	1,202,785
CMBS
Available for sale
Amortized cost	996,699	1,029,863
Allowance for expected credit losses	0	0
Gross unrealized gains	165	60
Gross unrealized losses	(73,361)	(82,145)
Fair value	923,503	947,778
Non-agency RMBS
Available for sale
Amortized cost	145,288	151,907
Allowance for expected credit losses	(98)	(123)
Gross unrealized gains	134	275
Gross unrealized losses	(15,839)	(18,525)
Fair value	129,485	133,534
ABS
Available for sale
Amortized cost	1,454,488	1,499,728
Allowance for expected credit losses	(36)	(35)
Gross unrealized gains	828	555
Gross unrealized losses	(57,897)	(70,721)
Fair value	1,397,383	1,429,527
Municipals
Available for sale
Amortized cost	160,641	172,475
Allowance for expected credit losses	(47)	(54)
Gross unrealized gains	317	139
Gross unrealized losses	(12,489)	(16,205)
Fair value	$ 148,422	$ 156,355

INVESTMENTS - Contractual Matur

INVESTMENTS - Contractual Maturities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Amortized cost
Due in one year or less	$ 576,989	$ 422,039
Due after one year through five years	5,400,687	5,349,123
Due after five years through ten years	2,171,234	2,192,344
Due after ten years	174,926	234,046
Total fixed maturities with a single maturity date	8,323,836	8,197,552
Amortized cost, Total	12,264,498	12,176,473
Fair value
Due in one year or less	563,123	409,972
Due after one year through five years	5,204,250	5,078,273
Due after five years through ten years	1,974,369	1,919,450
Due after ten years	163,281	205,575
Total fixed maturities with a single maturity date	7,905,023	7,613,270
Fair value, Total	$ 11,627,555	$ 11,326,894
% of Total fair value
Due in one year or less	4.90%	3.70%
Due after one year through five years (as a percent)	44.80%	44.80%
Due after five years through ten years (as a percent)	17%	16.90%
Due after ten years (as a percent)	1.40%	1.80%
Fixed maturities with a single maturity date (as a percent)	68.10%	67.20%
Total (as a percent)	100%	100%
Agency RMBS
Amortized cost
Fixed maturities without a single maturity date	$ 1,344,187	$ 1,297,423
Amortized cost, Total	1,344,187	1,297,423
Fair value
Fixed maturities without a single maturity date	1,272,161	1,202,785
Fair value, Total	$ 1,272,161	$ 1,202,785
% of Total fair value
Fixed maturities without a single maturity date (as a percent)	10.90%	10.60%
CMBS
Amortized cost
Fixed maturities without a single maturity date	$ 996,699	$ 1,029,863
Amortized cost, Total	996,699	1,029,863
Fair value
Fixed maturities without a single maturity date	923,503	947,778
Fair value, Total	$ 923,503	$ 947,778
% of Total fair value
Fixed maturities without a single maturity date (as a percent)	7.90%	8.40%
Non-agency RMBS
Amortized cost
Fixed maturities without a single maturity date	$ 145,288	$ 151,907
Amortized cost, Total	145,288	151,907
Fair value
Fixed maturities without a single maturity date	129,485	133,534
Fair value, Total	$ 129,485	$ 133,534
% of Total fair value
Fixed maturities without a single maturity date (as a percent)	1.10%	1.20%
ABS
Amortized cost
Fixed maturities without a single maturity date	$ 1,454,488	$ 1,499,728
Amortized cost, Total	1,454,488	1,499,728
Fair value
Fixed maturities without a single maturity date	1,397,383	1,429,527
Fair value, Total	$ 1,397,383	$ 1,429,527
% of Total fair value
Fixed maturities without a single maturity date (as a percent)	12%	12.60%
Held-to-maturity securities without a single maturity date	$ 632,000	$ 613,000
Corporate debt
Amortized cost
Amortized cost, Total	4,619,198	4,680,798
Fair value
Fair value, Total	4,297,212	4,255,556
% of Total fair value
Held-to-maturity securities with maturity after three years through 10 years	81,000	81,000
Held-to-maturity securities with maturity after ten years	$ 4,000	$ 4,000
Corporate debt | Minimum
% of Total fair value
Debt securities, held-to-maturity, maturity period	3 years
Corporate debt | Maximum
% of Total fair value
Debt securities, held-to-maturity, maturity period	10 years

INVESTMENTS - Gross Unrealized

INVESTMENTS - Gross Unrealized Losses (Details) $ in Thousands	Mar. 31, 2023 USD ($) security	Dec. 31, 2022 USD ($) security
Fixed maturities, available for sale
Fair value
12 months or greater	$ 6,253,850	$ 3,615,234
Less than 12 months	2,779,448	6,269,478
Total	9,033,298	9,884,712
Unrealized losses
12 months or greater	(583,859)	(497,762)
Less than 12 months	(82,502)	(358,826)
Total	$ (666,361)	$ (856,588)
Number of securities in unrealized loss position | security	4,372	4,525
Number of securities in a continuous unrealized loss position | security	3,154	1,842
Fixed maturities, available for sale | Below Investment Grade or Not Rated
Unrealized losses
Total	$ (47,000)	$ (64,000)
U.S. government and agency
Fair value
12 months or greater	808,593	467,032
Less than 12 months	738,852	1,414,181
Total	1,547,445	1,881,213
Unrealized losses
12 months or greater	(51,696)	(41,365)
Less than 12 months	(18,799)	(56,424)
Total	(70,495)	(97,789)
Non-U.S. government
Fair value
12 months or greater	263,740	207,637
Less than 12 months	109,543	298,048
Total	373,283	505,685
Unrealized losses
12 months or greater	(31,114)	(33,027)
Less than 12 months	(2,215)	(19,885)
Total	(33,329)	(52,912)
Corporate debt
Fair value
12 months or greater	2,499,437	1,562,355
Less than 12 months	1,166,503	2,350,504
Total	3,665,940	3,912,859
Unrealized losses
12 months or greater	(287,339)	(268,289)
Less than 12 months	(34,475)	(150,701)
Total	(321,814)	(418,990)
Agency RMBS
Fair value
12 months or greater	533,145	220,595
Less than 12 months	433,607	771,191
Total	966,752	991,786
Unrealized losses
12 months or greater	(64,620)	(40,469)
Less than 12 months	(16,517)	(58,832)
Total	(81,137)	(99,301)
CMBS
Fair value
12 months or greater	764,365	343,494
Less than 12 months	140,843	599,877
Total	905,208	943,371
Unrealized losses
12 months or greater	(66,063)	(40,888)
Less than 12 months	(7,298)	(41,257)
Total	(73,361)	(82,145)
Non-agency RMBS
Fair value
12 months or greater	99,758	75,137
Less than 12 months	23,591	53,484
Total	123,349	128,621
Unrealized losses
12 months or greater	(15,383)	(14,691)
Less than 12 months	(456)	(3,834)
Total	(15,839)	(18,525)
ABS
Fair value
12 months or greater	1,179,697	685,990
Less than 12 months	134,693	686,190
Total	1,314,390	1,372,180
Unrealized losses
12 months or greater	(56,118)	(48,913)
Less than 12 months	(1,779)	(21,808)
Total	(57,897)	(70,721)
Municipals
Fair value
12 months or greater	105,115	52,994
Less than 12 months	31,816	96,003
Total	136,931	148,997
Unrealized losses
12 months or greater	(11,526)	(10,120)
Less than 12 months	(963)	(6,085)
Total	$ (12,489)	$ (16,205)

INVESTMENTS - Fixed Maturitie_2

INVESTMENTS - Fixed Maturities Held to Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Held to maturity
Amortized cost	$ 716,768	$ 698,351
Allowance for expected credit losses	0	0
Net carrying value	716,768	698,351
Gross unrealized gains	0	0
Gross unrealized losses	(19,993)	(23,608)
Fair value	696,775	674,743
Corporate debt
Held to maturity
Amortized cost	85,200	85,200
Allowance for expected credit losses	0	0
Net carrying value	85,200	85,200
Gross unrealized gains	0	0
Gross unrealized losses	(9,535)	(11,428)
Fair value	75,665	73,772
ABS
Held to maturity
Amortized cost	631,568	613,151
Allowance for expected credit losses	0	0
Net carrying value	631,568	613,151
Gross unrealized gains	0	0
Gross unrealized losses	(10,458)	(12,180)
Fair value	$ 621,110	$ 600,971

INVESTMENTS - Narrative (Detail

INVESTMENTS - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Net carrying value of fixed investments held to maturity	$ 716,768	$ 698,351
ABS
Debt Securities, Available-for-sale [Line Items]
Net carrying value of fixed investments held to maturity	631,568	613,151
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Net carrying value of fixed investments held to maturity	$ 85,200	$ 85,200

INVESTMENTS - Equity Securities

INVESTMENTS - Equity Securities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 559,293	$ 494,356
Gross unrealized gains	83,894	68,694
Gross unrealized losses	(69,271)	(77,797)
Fair value	$ 573,916	485,253
Limited partnership
Debt and Equity Securities, FV-NI [Line Items]
Percentage of investment composition (as a percent)	71%
Common stocks
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 3,130	7,279
Gross unrealized gains	321	636
Gross unrealized losses	(437)	(442)
Fair value	3,014	7,473
Preferred stocks
Debt and Equity Securities, FV-NI [Line Items]
Cost	115	115
Gross unrealized gains	0	0
Gross unrealized losses	(113)	(43)
Fair value	2	72
Exchange-traded funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	199,212	207,505
Gross unrealized gains	83,523	68,058
Gross unrealized losses	(3,016)	(5,757)
Fair value	279,719	269,806
Bond mutual funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	356,836	279,457
Gross unrealized gains	50	0
Gross unrealized losses	(65,705)	(71,555)
Fair value	$ 291,181	$ 207,902

INVESTMENTS - Mortgage Loans (D

INVESTMENTS - Mortgage Loans (Details)	Mar. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($)	Mar. 31, 2022
Mortgage loans, held for investment:
Commercial	$ 636,370,000	$ 627,437,000
Commercial (as a percent)	100%	100%
Allowance for expected credit losses	$ (1,900,000)	$ 0
Allowance for expected credit losses (as a percent)	0%	0%
Total mortgage loans, held for investment	$ 634,470,000	$ 627,437,000
Total mortgage loans, held-for investment (as a percent)	100%	100%
Weighted average debt service coverage ratios	2.2		2.3
Weighted average loan-to-value ratios (as a percent)	60%		60%
Commercial mortgage loans, past due amount	$ 0	$ 0
Number of collateral dependent loan | loan	1
Allowance for expected credit losses	$ 1,900,000	$ 0

INVESTMENTS - Other Investments

INVESTMENTS - Other Investments (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023 USD ($) fund	Dec. 31, 2022 USD ($)
Other Investments [Line Items]
Other investments, at fair value	$ 1,008,887	$ 996,751
Percentage of total fair value (as a percent)	100%	100%
Multi-strategy funds
Other Investments [Line Items]
Other investments, at fair value	$ 30,721	$ 32,616
Percentage of total fair value (as a percent)	3%	3%
Multi-strategy funds | Minimum
Other Investments [Line Items]
Redemption notice period	60 days	60 days
Multi-strategy funds | Maximum
Other Investments [Line Items]
Redemption notice period	90 days	90 days
Multi-strategy funds | Other Redemption Restriction
Other Investments [Line Items]
Unfunded commitments related to other investments	$ 26,000	$ 26,000
Multi-strategy funds | Other Redemption Restriction | Minimum
Other Investments [Line Items]
Investment term	2 years
Direct lending funds
Other Investments [Line Items]
Other investments, at fair value	$ 258,183	$ 258,626
Percentage of total fair value (as a percent)	26%	26%
Redemption notice period	90 days	90 days
Direct lending funds | Other Redemption Restriction
Other Investments [Line Items]
Unfunded commitments related to other investments	$ 197,000	$ 183,000
Optional extension of investment term	3 years
Direct lending funds | Other Redemption Restriction | Minimum
Other Investments [Line Items]
Investment term	4 years
Direct lending funds | Other Redemption Restriction | Maximum
Other Investments [Line Items]
Investment term	12 years
Direct lending funds | Quarterly Redemption
Other Investments [Line Items]
Other investments, at fair value	$ 35,000	39,000
Number of funds | fund	1
Private equity funds
Other Investments [Line Items]
Other investments, at fair value	$ 273,859	$ 265,836
Percentage of total fair value (as a percent)	27%	27%
Private equity funds | Other Redemption Restriction
Other Investments [Line Items]
Unfunded commitments related to other investments	$ 166,000	$ 158,000
Investment term	5 years
Real estate funds
Other Investments [Line Items]
Other investments, at fair value	$ 300,152	$ 298,499
Percentage of total fair value (as a percent)	30%	30%
Real estate funds | Minimum
Other Investments [Line Items]
Redemption notice period	45 days	45 days
Real estate funds | Maximum
Other Investments [Line Items]
Redemption notice period	90 days	90 days
Real estate funds | Other Redemption Restriction
Other Investments [Line Items]
Unfunded commitments related to other investments	$ 136,000	$ 141,000
Real estate funds | Other Redemption Restriction | Minimum
Other Investments [Line Items]
Investment term	2 years
Real estate funds | Quarterly Redemption
Other Investments [Line Items]
Other investments, at fair value	$ 72,000	73,000
Number of funds | fund	1
Real estate funds | Annual Redemption
Other Investments [Line Items]
Other investments, at fair value	$ 25,000	27,000
Number of funds | fund	1
CLO-Equities
Other Investments [Line Items]
Other investments, at fair value	$ 5,019	$ 5,016
Percentage of total fair value (as a percent)	0%	0%
Other privately held investments
Other Investments [Line Items]
Other investments, at fair value	$ 140,953	$ 136,158
Percentage of total fair value (as a percent)	14%	14%
Hedge funds | Lockup Redemption Restriction
Other Investments [Line Items]
Fair value of other investments subject to redemption restrictions	$ 0	$ 0

INVESTMENTS - Equity Method Inv

INVESTMENTS - Equity Method Investments (Details) - Harrington Reinsurance Holdings Limited $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments	$ 108
Equity method investment, ownership percentage (as a percent)	19%
Equity method investment, difference between carrying amount and underlying equity	$ 5

INVESTMENTS - Net Investment In

INVESTMENTS - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net Investment Income [Line Items]
Gross investment income	$ 141,261	$ 98,478
Investment expenses	(7,490)	(7,123)
Net investment income	133,771	91,355
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	118,262	64,809
Other investments
Net Investment Income [Line Items]
Gross investment income	486	26,050
Equity securities
Net Investment Income [Line Items]
Gross investment income	2,455	2,172
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	8,386	4,163
Cash and cash equivalents
Net Investment Income [Line Items]
Gross investment income	10,012	1,118
Short-term investments
Net Investment Income [Line Items]
Gross investment income	$ 1,660	$ 166

INVESTMENTS - Net Investment Ga

INVESTMENTS - Net Investment Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Gross realized investment gains
Fixed maturities and short-term investments	$ 12,370	$ 10,422
Equity securities	1,517	0
Gross realized investment gains	13,887	10,422
Gross realized investment losses
Fixed maturities and short-term investments	(53,649)	(63,146)
Equity securities	(396)	(225)
Gross realized investment losses	(54,045)	(63,371)
(Increase) decrease in allowance for expected credit losses, fixed maturities, available for sale	(911)	(70)
(Increase) decrease in allowance for expected credit losses, mortgage loans	(1,900)	0
Impairment losses	0	(109)
Change in fair value of investment derivatives	(947)	2,242
Net unrealized gains (losses) on equity securities	23,726	(43,622)
Total net investment losses	$ (20,190)	$ (94,508)

INVESTMENTS - Summary of Allowa

INVESTMENTS - Summary of Allowance for Expected Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 11,733	$ 313
Expected credit losses on securities where credit losses were not previously recognized	613	9
Additions (reductions) for expected credit losses on securities where credit losses were previously recognized	919	78
Impairments of securities which the Company intends to sell or more likely than not will be required to sell	0	0
Securities sold/redeemed/matured	(620)	(17)
Balance at end of period	$ 12,645	$ 383

INVESTMENTS - Reverse Repurchas

INVESTMENTS - Reverse Repurchase Agreements (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Value of reverse repurchase agreements	$ 45	$ 0
Minimum required collateral for reverse repurchase agreements, expressed as a percentage of loan principal (as a percent)	102%

FAIR VALUE MEASUREMENTS - Finan

FAIR VALUE MEASUREMENTS - Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Assets
Fixed maturities, available for sale	$ 11,627,555	$ 11,326,894
Equity securities	573,916	485,253
Other investments	1,008,887	996,751
Short-term investments	70,416	70,310
Derivative instruments (refer to Note 5)	7,752	37,682
Total Assets	13,288,526	12,916,890
Liabilities
Derivative instruments	2,789	703
Cash-settled awards	0	4,792
Total Liabilities	2,789	5,495
U.S. government and agency
Assets
Fixed maturities, available for sale	2,901,312	2,639,330
Non-U.S. government
Assets
Fixed maturities, available for sale	558,077	562,029
Corporate debt
Assets
Fixed maturities, available for sale	4,297,212	4,255,556
Agency RMBS
Assets
Fixed maturities, available for sale	1,272,161	1,202,785
CMBS
Assets
Fixed maturities, available for sale	923,503	947,778
Non-agency RMBS
Assets
Fixed maturities, available for sale	129,485	133,534
ABS
Assets
Fixed maturities, available for sale	1,397,383	1,429,527
Municipals
Assets
Fixed maturities, available for sale	148,422	156,355
Common stocks
Assets
Equity securities	3,014	7,473
Preferred stocks
Assets
Equity securities	2	72
Exchange-traded funds
Assets
Equity securities	279,719	269,806
Bond mutual funds
Assets
Equity securities	291,181	207,902
Multi-strategy funds
Assets
Other investments	30,721	32,616
Direct lending funds
Assets
Other investments	258,183	258,626
Private equity funds
Assets
Other investments	273,859	265,836
Real estate funds
Assets
Other investments	300,152	298,499
CLO-Equities
Assets
Other investments	5,019	5,016
Other privately held investments
Assets
Other investments	140,953	136,158
Quoted prices in active markets for identical assets (Level 1)
Assets
Fixed maturities, available for sale	2,862,087	2,600,636
Equity securities	282,735	277,351
Other investments	0	0
Short-term investments	0	0
Derivative instruments (refer to Note 5)	0	0
Total Assets	3,144,822	2,877,987
Liabilities
Derivative instruments	0	0
Cash-settled awards	0	0
Total Liabilities	0	0
Quoted prices in active markets for identical assets (Level 1) | U.S. government and agency
Assets
Fixed maturities, available for sale	2,862,087	2,600,636
Quoted prices in active markets for identical assets (Level 1) | Non-U.S. government
Assets
Fixed maturities, available for sale	0	0
Quoted prices in active markets for identical assets (Level 1) | Corporate debt
Assets
Fixed maturities, available for sale	0	0
Quoted prices in active markets for identical assets (Level 1) | Agency RMBS
Assets
Fixed maturities, available for sale	0	0
Quoted prices in active markets for identical assets (Level 1) | CMBS
Assets
Fixed maturities, available for sale	0	0
Quoted prices in active markets for identical assets (Level 1) | Non-agency RMBS
Assets
Fixed maturities, available for sale	0	0
Quoted prices in active markets for identical assets (Level 1) | ABS
Assets
Fixed maturities, available for sale	0	0
Quoted prices in active markets for identical assets (Level 1) | Municipals
Assets
Fixed maturities, available for sale	0	0
Quoted prices in active markets for identical assets (Level 1) | Common stocks
Assets
Equity securities	3,014	7,473
Quoted prices in active markets for identical assets (Level 1) | Preferred stocks
Assets
Equity securities	2	72
Quoted prices in active markets for identical assets (Level 1) | Exchange-traded funds
Assets
Equity securities	279,719	269,806
Quoted prices in active markets for identical assets (Level 1) | Bond mutual funds
Assets
Equity securities	0	0
Quoted prices in active markets for identical assets (Level 1) | Multi-strategy funds
Assets
Other investments	0	0
Quoted prices in active markets for identical assets (Level 1) | Direct lending funds
Assets
Other investments	0	0
Quoted prices in active markets for identical assets (Level 1) | Private equity funds
Assets
Other investments	0	0
Quoted prices in active markets for identical assets (Level 1) | Real estate funds
Assets
Other investments	0	0
Quoted prices in active markets for identical assets (Level 1) | CLO-Equities
Assets
Other investments	0	0
Quoted prices in active markets for identical assets (Level 1) | Other privately held investments
Assets
Other investments	0	0
Significant other observable inputs (Level 2)
Assets
Fixed maturities, available for sale	8,635,041	8,607,154
Equity securities	291,181	207,902
Other investments	0	0
Short-term investments	70,416	70,310
Derivative instruments (refer to Note 5)	7,752	37,682
Total Assets	9,004,390	8,923,048
Liabilities
Derivative instruments	2,789	703
Cash-settled awards	0	4,792
Total Liabilities	2,789	5,495
Significant other observable inputs (Level 2) | U.S. government and agency
Assets
Fixed maturities, available for sale	39,225	38,694
Significant other observable inputs (Level 2) | Non-U.S. government
Assets
Fixed maturities, available for sale	558,077	562,029
Significant other observable inputs (Level 2) | Corporate debt
Assets
Fixed maturities, available for sale	4,166,785	4,136,452
Significant other observable inputs (Level 2) | Agency RMBS
Assets
Fixed maturities, available for sale	1,272,161	1,202,785
Significant other observable inputs (Level 2) | CMBS
Assets
Fixed maturities, available for sale	923,503	947,778
Significant other observable inputs (Level 2) | Non-agency RMBS
Assets
Fixed maturities, available for sale	129,485	133,534
Significant other observable inputs (Level 2) | ABS
Assets
Fixed maturities, available for sale	1,397,383	1,429,527
Significant other observable inputs (Level 2) | Municipals
Assets
Fixed maturities, available for sale	148,422	156,355
Significant other observable inputs (Level 2) | Common stocks
Assets
Equity securities	0	0
Significant other observable inputs (Level 2) | Preferred stocks
Assets
Equity securities	0	0
Significant other observable inputs (Level 2) | Exchange-traded funds
Assets
Equity securities	0	0
Significant other observable inputs (Level 2) | Bond mutual funds
Assets
Equity securities	291,181	207,902
Significant other observable inputs (Level 2) | Multi-strategy funds
Assets
Other investments	0	0
Significant other observable inputs (Level 2) | Direct lending funds
Assets
Other investments	0	0
Significant other observable inputs (Level 2) | Private equity funds
Assets
Other investments	0	0
Significant other observable inputs (Level 2) | Real estate funds
Assets
Other investments	0	0
Significant other observable inputs (Level 2) | CLO-Equities
Assets
Other investments	0	0
Significant other observable inputs (Level 2) | Other privately held investments
Assets
Other investments	0	0
Significant unobservable inputs (Level 3)
Assets
Fixed maturities, available for sale	130,427	119,104
Equity securities	0	0
Other investments	145,972	141,174
Short-term investments	0	0
Derivative instruments (refer to Note 5)	0	0
Total Assets	276,399	260,278
Liabilities
Derivative instruments	0	0
Cash-settled awards	0	0
Total Liabilities	0	0
Significant unobservable inputs (Level 3) | U.S. government and agency
Assets
Fixed maturities, available for sale	0	0
Significant unobservable inputs (Level 3) | Non-U.S. government
Assets
Fixed maturities, available for sale	0	0
Significant unobservable inputs (Level 3) | Corporate debt
Assets
Fixed maturities, available for sale	130,427	119,104
Significant unobservable inputs (Level 3) | Agency RMBS
Assets
Fixed maturities, available for sale	0	0
Significant unobservable inputs (Level 3) | CMBS
Assets
Fixed maturities, available for sale	0	0
Significant unobservable inputs (Level 3) | Non-agency RMBS
Assets
Fixed maturities, available for sale	0	0
Significant unobservable inputs (Level 3) | ABS
Assets
Fixed maturities, available for sale	0	0
Significant unobservable inputs (Level 3) | Municipals
Assets
Fixed maturities, available for sale	0	0
Significant unobservable inputs (Level 3) | Common stocks
Assets
Equity securities	0	0
Significant unobservable inputs (Level 3) | Preferred stocks
Assets
Equity securities	0	0
Significant unobservable inputs (Level 3) | Exchange-traded funds
Assets
Equity securities	0	0
Significant unobservable inputs (Level 3) | Bond mutual funds
Assets
Equity securities	0	0
Significant unobservable inputs (Level 3) | Multi-strategy funds
Assets
Other investments	0	0
Significant unobservable inputs (Level 3) | Direct lending funds
Assets
Other investments	0	0
Significant unobservable inputs (Level 3) | Private equity funds
Assets
Other investments	0	0
Significant unobservable inputs (Level 3) | Real estate funds
Assets
Other investments	0	0
Significant unobservable inputs (Level 3) | CLO-Equities
Assets
Other investments	5,019	5,016
Significant unobservable inputs (Level 3) | Other privately held investments
Assets
Other investments	140,953	136,158
Fair value based on NAV practical expedient
Assets
Other investments	862,915	855,577
Total Assets	862,915	855,577
Fair value based on NAV practical expedient | Multi-strategy funds
Assets
Other investments	30,721	32,616
Fair value based on NAV practical expedient | Direct lending funds
Assets
Other investments	258,183	258,626
Fair value based on NAV practical expedient | Private equity funds
Assets
Other investments	273,859	265,836
Fair value based on NAV practical expedient | Real estate funds
Assets
Other investments	$ 300,152	$ 298,499

FAIR VALUE MEASUREMENTS - Signi

FAIR VALUE MEASUREMENTS - Significant Unobservable Inputs (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value Inputs Assets Quantitative Information [Line Items]
Other investments, at fair value	$ 1,008,887	$ 996,751
Fixed maturities, available for sale	11,627,555	11,326,894
Significant unobservable inputs (Level 3)
Fair Value Inputs Assets Quantitative Information [Line Items]
Other investments, at fair value	145,972	141,174
Fixed maturities, available for sale	130,427	$ 119,104
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow
Fair Value Inputs Assets Quantitative Information [Line Items]
Other investments, at fair value	$ 5,019
Estimated maturity date	5 years
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Estimated maturity date	5 years
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow | Default rate
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.045
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow | Default rate | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.045
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow | Loss severity rate
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.500
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow | Loss severity rate | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.500
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow | Collateral spread
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.030
Significant unobservable inputs (Level 3) | Other investments - CLO-Equities | Discounted cash flow | Collateral spread | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.030
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow
Fair Value Inputs Assets Quantitative Information [Line Items]
Other investments, at fair value	$ 17,522
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Estimated maturity date	2 years
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Minimum
Fair Value Inputs Assets Quantitative Information [Line Items]
Estimated maturity date	1 year
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Maximum
Fair Value Inputs Assets Quantitative Information [Line Items]
Estimated maturity date	3 years
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Discount rate
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.066
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Discount rate | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.066
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Default rate
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.005
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Default rate | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.005
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Loss absorption yield
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.010
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Discounted cash flow | Loss absorption yield | Weighted average
Fair Value Inputs Assets Quantitative Information [Line Items]
Unobservable input (as a percent)	0.010
Significant unobservable inputs (Level 3) | Other investments - Other privately held investments | Valuation, Market Approach
Fair Value Inputs Assets Quantitative Information [Line Items]
Other investments, at fair value	$ 123,000

FAIR VALUE MEASUREMENTS - Chang

FAIR VALUE MEASUREMENTS - Changes in Level 3 for Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	$ 260,278	$ 153,325
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	740	2,490
Included in OCI	1,183	(2,794)
Purchases	23,369	30,797
Sales	0	0
Settlements/ distributions	(9,171)	(2,573)
Closing balance	276,399	181,245
Change in unrealized investment gains/(losses)	747	2,490
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	0	5,630
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	0	(556)
Included in OCI	0	0
Purchases	0	0
Sales	0	0
Settlements/ distributions	0	0
Closing balance	0	5,074
Change in unrealized investment gains/(losses)	0	(556)
Other liabilities | Derivative instruments
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	0	5,630
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	0	(556)
Included in OCI	0	0
Purchases	0	0
Sales	0	0
Settlements/ distributions	0	0
Closing balance	0	5,074
Change in unrealized investment gains/(losses)	0	(556)
Fixed maturities, available for sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	119,104	42,894
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	(7)	0
Included in OCI	1,183	(2,794)
Purchases	18,910	21,462
Sales	0	0
Settlements/ distributions	(8,763)	(672)
Closing balance	130,427	60,890
Change in unrealized investment gains/(losses)	0	0
Fixed maturities, available for sale | Corporate debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	119,104	42,894
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	(7)	0
Included in OCI	1,183	(2,794)
Purchases	18,910	21,462
Sales	0	0
Settlements/ distributions	(8,763)	(672)
Closing balance	130,427	60,890
Change in unrealized investment gains/(losses)	0	0
Other investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	141,174	110,431
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	747	2,490
Included in OCI	0	0
Purchases	4,459	9,335
Sales	0	0
Settlements/ distributions	(408)	(1,901)
Closing balance	145,972	120,355
Change in unrealized investment gains/(losses)	747	2,490
Other investments | CLO-Equities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	5,016	5,910
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	411	872
Included in OCI	0	0
Purchases	0	0
Sales	0	0
Settlements/ distributions	(408)	(1,901)
Closing balance	5,019	4,881
Change in unrealized investment gains/(losses)	411	872
Other investments | Other privately held investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	136,158	104,521
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Included in net income	336	1,618
Included in OCI	0	0
Purchases	4,459	9,335
Sales	0	0
Settlements/ distributions	0	0
Closing balance	140,953	115,474
Change in unrealized investment gains/(losses)	$ 336	$ 1,618

FAIR VALUE MEASUREMENTS - Fin_2

FAIR VALUE MEASUREMENTS - Financial Instruments Disclosed, But Not Carried, at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Amortized cost	$ 716,768	$ 698,351
Fair value	696,775	674,743
Federal Home Loan Bank advances	85,790	81,388
Federal Home Loan Bank advances, fair value	86,000	81,000
Reported value measurement
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Notes payable	1,313,000	1,312,000
Estimate of fair value measurement
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Notes payable	$ 1,188,000	$ 1,160,000

DERIVATIVE INSTRUMENTS - Schedu

DERIVATIVE INSTRUMENTS - Schedule of Derivative Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative asset fair value	$ 7,752	$ 37,682
Derivative liability fair value	$ 2,789	$ 703
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities	Other liabilities
Not Designated as Hedging Instruments
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative asset fair value	$ 7,752	$ 37,682
Derivative liability fair value	2,789	703
Not Designated as Hedging Instruments | Relating to investment portfolio: | Foreign exchange forward contracts
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative notional amount	51,959	54,076
Derivative asset fair value	0	81
Derivative liability fair value	1,244	559
Not Designated as Hedging Instruments | Relating to underwriting portfolio: | Foreign exchange forward contracts
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative notional amount	1,318,403	1,441,273
Derivative asset fair value	7,752	37,601
Derivative liability fair value	$ 1,545	$ 144

DERIVATIVE INSTRUMENTS - Offset

DERIVATIVE INSTRUMENTS - Offsetting Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Derivative assets
Gross amounts	$ 11,632	$ 41,762
Gross amounts offset	(3,880)	(4,080)
Net amounts	7,752	37,682
Derivative liabilities
Gross amounts	6,669	4,783
Gross amounts offset	(3,880)	(4,080)
Net amounts	$ 2,789	$ 703

DERIVATIVE INSTRUMENTS - Gains

DERIVATIVE INSTRUMENTS - Gains (Losses) on Derivatives Recognized in Net Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Unrealized and Realized Gains (Losses) Recognized in Earnings for Derivatives Not Designated As Hedges [Line Items]
Unrealized and realized gains (losses) recognized in earnings for derivatives not designated as hedges	$ 10,303	$ (25,179)
Relating to investment portfolio: | Foreign exchange forward contracts | Net investment gains (losses)
Unrealized and Realized Gains (Losses) Recognized in Earnings for Derivatives Not Designated As Hedges [Line Items]
Unrealized and realized gains (losses) recognized in earnings for derivatives not designated as hedges	(947)	2,242
Relating to underwriting portfolio: | Foreign exchange forward contracts | Foreign exchange (losses) gains
Unrealized and Realized Gains (Losses) Recognized in Earnings for Derivatives Not Designated As Hedges [Line Items]
Unrealized and realized gains (losses) recognized in earnings for derivatives not designated as hedges	11,250	(27,976)
Relating to underwriting portfolio: | Other Contract | Other insurance related income (losses)
Unrealized and Realized Gains (Losses) Recognized in Earnings for Derivatives Not Designated As Hedges [Line Items]
Unrealized and realized gains (losses) recognized in earnings for derivatives not designated as hedges	$ 0	$ 555

RESERVE FOR LOSSES AND LOSS E_3

RESERVE FOR LOSSES AND LOSS EXPENSES - Reserve Roll-Forward (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross reserve for losses and loss expenses, beginning of period	$ 15,168,863	$ 14,653,094
Less reinsurance recoverable on unpaid losses and loss expenses, beginning of period	(5,831,172)	(5,017,611)
Net reserve for unpaid losses and loss expenses, beginning of period	9,337,691	9,635,483
Net incurred losses and loss expenses related to:
Current year	724,680	741,655
Prior years	(4,038)	(8,956)
Net incurred losses and loss expenses	720,642	732,699
Net paid losses and loss expenses related to:
Current year	(38,662)	(32,477)
Prior years	(574,538)	(750,969)
Net paid losses and loss expenses	(613,200)	(783,446)
Foreign exchange and other	46,094	(71,661)
Net reserve for unpaid losses and loss expenses, end of period	9,491,227	9,513,075
Reinsurance recoverable on unpaid losses and loss expenses, end of period	5,823,417	4,957,080
Gross reserve for losses and loss expenses, end of period	$ 15,314,644	$ 14,470,155

RESERVE FOR LOSSES AND LOSS E_4

RESERVE FOR LOSSES AND LOSS EXPENSES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Net loss and loss expenses	$ 724,680	$ 741,655
Catastrophe and Weather-related Events
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Net loss and loss expenses	$ 38,000	$ 60,000

RESERVE FOR LOSSES AND LOSS E_5

RESERVE FOR LOSSES AND LOSS EXPENSES - Prior Year Development (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior years - net favorable (adverse) effect	$ 4,038	$ 8,956
Insurance
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior years - net favorable (adverse) effect	1,041	7,062
Reinsurance
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior years - net favorable (adverse) effect	$ 2,997	$ 1,894

RESERVE FOR LOSSES AND LOSS E_6

RESERVE FOR LOSSES AND LOSS EXPENSES - Prior Year Reserve Development By Segment and Line of Business (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	$ 4,038	$ 8,956
Insurance
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	1,041	7,062
Insurance | Property
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	5,900	8,060
Insurance | Accident and health
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(304)	3,632
Insurance | Marine and aviation
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	13,221	14,647
Insurance | Cyber
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	8,452	(687)
Insurance | Professional lines
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(12,594)	(5,936)
Insurance | Credit and political risk
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	4,519	895
Insurance | Liability
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(18,153)	(13,549)
Reinsurance
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	2,997	1,894
Reinsurance | Accident and health
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	6,988	(499)
Reinsurance | Marine and aviation
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(250)	497
Reinsurance | Professional lines
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(3,225)	(24,522)
Reinsurance | Liability
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(32,853)	(4,105)
Reinsurance | Agriculture
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	11,891	1,231
Reinsurance | Credit and surety
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(546)	7,465
Reinsurance | Motor
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	(17,122)	(1,730)
Reinsurance | Run Off Lines
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	38,114	23,557
Reinsurance | Run Off Lines | Property
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	6,883	22,539
Reinsurance | Run Off Lines | Catastrophe
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	31,058	(246)
Reinsurance | Run Off Lines | Engineering
Liability for Future Policy Benefit, by Product Segment [Line Items]
Prior years - net favorable (adverse) effect	$ 173	$ 1,264

EARNINGS PER COMMON SHARE (Deta

EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Earnings per common share
Net income	$ 180,097	$ 149,200
Less: Preferred share dividends	7,563	7,563
Net income available to common shareholders	$ 172,534	$ 141,637
Weighted average common shares outstanding (in shares)	84,864	84,961
Earnings per common share (in usd per share)	$ 2.03	$ 1.67
Earnings per diluted common share
Net income available to common shareholders	$ 172,534	$ 141,637
Weighted average common shares outstanding (in shares)	84,864	84,961
Share-based compensation plans (in shares)	989	847
Weighted average diluted common shares outstanding (in shares)	85,853	85,808
Earnings per diluted common share (in usd per share)	$ 2.01	$ 1.65
Weighted average anti-dilutive shares excluded from the dilutive computation (in shares)	805	989

SHARE-BASED COMPENSATION - Narr

SHARE-BASED COMPENSATION - Narrative (Details) - trading_day	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Trading days proceeding and performance period	10	10
Performance Vesting Restricted Stock Units
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Vesting period	3 years
Performance Vesting Restricted Stock Units | Minimum
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Vesting as a percentage of target (percent)	0%
Performance Vesting Restricted Stock Units | Maximum
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Vesting as a percentage of target (percent)	200%
Performance Vesting Restricted Stock Units | Share-Based Payment Arrangement, Senior Leadership | Share-Based Payment Arrangement, Tranche One [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Vesting period	1 year
Number of awards vesting upon achievement of performance goal (percent)	50%
Performance Vesting Restricted Stock Units | Share-Based Payment Arrangement, Senior Leadership | Share-Based Payment Arrangement, Tranche Two [Member]
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Vesting period	3 years
Number of awards vesting upon achievement of performance goal (percent)	50%
Performance Vesting Restricted Stock Units | Share-Based Payment Arrangement, Senior Leadership | Share-Based Payment Arrangement, Tranche Two [Member] | Minimum
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Vesting as a percentage of target (percent)	0%
Performance Vesting Restricted Stock Units | Share-Based Payment Arrangement, Senior Leadership | Share-Based Payment Arrangement, Tranche Two [Member] | Maximum
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Vesting as a percentage of target (percent)	200%

SHARE-BASED COMPENSATION - Valu

SHARE-BASED COMPENSATION - Valuation Assumptions (Details) - Performance Vesting Restricted Stock Units	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Expected volatility (as a percent)	36.24%	33.44%
Expected term (in years)	3 years	3 years
Risk-free interest rate (as a percent)	3.79%	1.26%
Share-Based Payment Arrangement, Senior Leadership
Reconcilation of Beginning and Ending Balance of Nonvested Restricted Stock (including RSUs) [Line Items]
Expected volatility (as a percent)	29.30%
Expected term (in years)	1 year
Risk-free interest rate (as a percent)	4.61%

SHARE-BASED COMPENSATION - Shar

SHARE-BASED COMPENSATION - Share/Cash Settled Restricted Stock Units (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Weighted  average grant date fair value
Liability for cash-settled restricted stock units	$ 0		$ 4,792
Performance Vesting Restricted Stock Units | Share Settled
Number of restricted stock units
Nonvested restricted stock units - beginning of period (in shares)	330
Granted (in shares)	91
Vested (in shares)	(72)
Forfeited (in shares)	0
Nonvested restricted stock units - end of period (in shares)	349
Weighted  average grant date fair value
Nonvested restricted stock units - beginning of period (in usd per share)	$ 60.01
Granted (in usd per share)	72.14
Vested (in usd per share)	62.26
Forfeited (in usd per share)	0
Nonvested restricted stock units - end of period (in usd per share)	$ 62.73
Restricted Stock Units (RSUs)
Weighted  average grant date fair value
Share-based compensation expense	$ 12,526	$ 15,011
Tax benefits associated with share-based compensation expense	2,647	2,426
Fair value of restricted stock units vested	50,714	46,970
Unrecognized share-based compensation expense	$ 108,882	$ 125,964
Expected weighted average period associated with the recognition of unrecognized share-based compensation expense	2 years 9 months 18 days	2 years 10 months 24 days
Restricted Stock Units (RSUs) | Share Settled
Number of restricted stock units
Nonvested restricted stock units - beginning of period (in shares)	2,117
Granted (in shares)	750
Vested (in shares)	(705)
Forfeited (in shares)	(33)
Nonvested restricted stock units - end of period (in shares)	2,129
Weighted  average grant date fair value
Nonvested restricted stock units - beginning of period (in usd per share)	$ 53.16
Granted (in usd per share)	58.05
Vested (in usd per share)	54.02
Forfeited (in usd per share)	53.67
Nonvested restricted stock units - end of period (in usd per share)	$ 54.59
Restricted Stock Units (RSUs) | Cash Settled
Number of restricted stock units
Nonvested restricted stock units - beginning of period (in shares)	60
Granted (in shares)	0
Vested (in shares)	(59)
Forfeited (in shares)	(1)
Nonvested restricted stock units - end of period (in shares)	0
Weighted  average grant date fair value
Liability for cash-settled restricted stock units	$ 0	$ 3,023

SHAREHOLDERS' EQUITY - Common S

SHAREHOLDERS' EQUITY - Common Shares Issued and Outstanding (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued, balance at beginning of period (in shares)	176,580
Total shares issued at end of period (in shares)	176,580
Treasury shares, balance at beginning of period (in shares)	(91,912)
Total treasury shares at end of period (in shares)	(91,397)
Total shares outstanding (in shares)	85,183		84,668
Common shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued, balance at beginning of period (in shares)	176,580	176,580
Shares issued (in shares)	0	0
Total shares issued at end of period (in shares)	176,580	176,580
Treasury shares, balance at beginning of period (in shares)	(91,912)	(91,806)
Shares repurchased (in shares)	(262)	(245)
Share reissued (in shares)	777	747
Total treasury shares at end of period (in shares)	(91,397)	(91,304)
Total shares outstanding (in shares)	85,183	85,276

SHAREHOLDERS' EQUITY - Treasury

SHAREHOLDERS' EQUITY - Treasury Shares (Details) - Common shares - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Treasury Shares [Line Items]
Total shares (in shares)	262	245
Total cost	$ 15,945	$ 12,977
Average price per share (in usd per share)	$ 60.82	$ 52.93
In the open market
Treasury Shares [Line Items]
Total shares (in shares)	0	0
Total cost	$ 0	$ 0
Average price per share (in usd per share)	$ 0	$ 0
From employees
Treasury Shares [Line Items]
Total shares (in shares)	262	245
Total cost	$ 15,945	$ 12,977
Average price per share (in usd per share)	$ 60.82	$ 52.93

SHAREHOLDERS' EQUITY - Dividend

SHAREHOLDERS' EQUITY - Dividends (Details) - $ / shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Common shares
Class of Stock [Line Items]
Dividends declared, Common shares (in USD per share)	$ 0.44	$ 0.43
Dividends paid in period of declaration, Common shares (in USD per share)	0	0
Dividends paid in period following declaration (in USD per share)	0.44	0.43
Series E preferred shares
Class of Stock [Line Items]
Dividends declared, Preferred shares (in USD per share)	34.38	34.38
Dividends paid in period of declaration, Preferred shares (in USD per share)	0	0
Dividends paid in period following declaration (in USD per share)	$ 34.38	$ 34.38

DEBT AND FINANCING ARRANGEMEN_2

DEBT AND FINANCING ARRANGEMENTS (Details) - Letter of Credit $ in Millions	Mar. 31, 2023 USD ($)
LOC Facility Two
Line of Credit Facility [Line Items]
Line of credit facility	$ 150
LOC Facility
Line of Credit Facility [Line Items]
Line of credit facility	$ 500

FEDERAL HOME LOAN BANK ADVANC_2

FEDERAL HOME LOAN BANK ADVANCES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Advance from Federal Home Loan Bank
Federal Home Loan Bank advances	$ 85,790	$ 81,388
Federal Home Loan Bank of Chicago
Advance from Federal Home Loan Bank
FHLB program, admitted assets, actual	3,000,000
FHLB program, maximum borrowing capacity	750,000
Federal Home Loan Bank advances	86,000
Interest expense on FHLB borrowings	1,000
FHLB program, investments pledged as security	$ 106,000
Federal Home Loan Bank of Chicago | Minimum
Advance from Federal Home Loan Bank
FHLB advances, interest rate (as a percent)	4.20%
Federal Home Loan Bank of Chicago | Maximum
Advance from Federal Home Loan Bank
FHLB advances, interest rate (as a percent)	5.50%

OTHER COMPREHENSIVE INCOME (L_3

OTHER COMPREHENSIVE INCOME (LOSS) - Tax Effects of Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Before tax amount
Unrealized gains (losses) arising during the period, net of reclassification adjustment	$ 212,922	$ (455,285)
Foreign currency translation adjustment	(535)	2,775
Total comprehensive income (loss), before tax	212,387	(452,510)
Income tax (expense) benefit
Unrealized gains (losses) arising during the period, net of reclassification adjustment	(23,983)	57,674
Foreign currency translation adjustment	0	0
Total comprehensive income (loss), net of tax	(23,983)	57,674
Net of tax amount
Unrealized gains (losses) arising during the period, net of reclassification adjustment	188,939	(397,611)
Foreign currency translation adjustment	(535)	2,775
Total other comprehensive income (loss), net of tax	188,404	(394,836)
Available for sale investments
Before tax amount
Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss)	44,121	52,916
Income tax (expense) benefit
Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss)	(3,371)	(7,573)
Net of tax amount
Adjustment for reclassification of net realized (gains) losses and impairment losses recognized in net income (loss)	40,750	45,343
Unrealized gains (losses) arising during the period, net of reclassification adjustment	188,939	(397,611)
Available for sale investments | Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has been recognized
Before tax amount
Unrealized gains (losses) arising during the period	153,851	(507,969)
Income tax (expense) benefit
Unrealized gains (losses) arising during the period	(19,284)	65,247
Net of tax amount
Unrealized gains (losses) arising during the period	134,567	(442,722)
Available for sale investments | Unrealized gains (losses) arising during the period for which an allowance for expected credit losses has not been recognized
Before tax amount
Unrealized gains (losses) arising during the period	14,950	(232)
Income tax (expense) benefit
Unrealized gains (losses) arising during the period	(1,328)	0
Net of tax amount
Unrealized gains (losses) arising during the period	$ 13,622	$ (232)

OTHER COMPREHENSIVE INCOME (L_4

OTHER COMPREHENSIVE INCOME (LOSS) - Reclassifications Out of AOCI Into Net Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Reclassification out of accumulated comprehensive income into net income available to common shareholders [Line Items]
Income before income taxes and interest in income (loss) of equity method investments	$ 198,198	$ 137,674
Income tax expense	(15,896)	(24)
Net income	180,097	149,200
Unrealized gains (losses) on available for sale investments | Reclassification out of Accumulated Other Comprehensive Income
Reclassification out of accumulated comprehensive income into net income available to common shareholders [Line Items]
Other realized gains (losses)	(44,121)	(52,807)
Impairment losses	0	(109)
Income before income taxes and interest in income (loss) of equity method investments	(44,121)	(52,916)
Income tax expense	3,371	7,573
Net income	$ (40,750)	$ (45,343)

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Other investments, at fair value	$ 1,008,887	$ 996,751
Investment In Related Party | Stone Point Capital, LLC
Related Party Transaction [Line Items]
Other investments, at fair value	$ 7,000