RenaissanceRe (RNR) 10-K 7 Feb 20 2019 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Feb. 03, 2020	Jun. 30, 2019
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	001-14428
Entity Registrant Name	RENAISSANCERE HOLDINGS LTD.
Entity Incorporation, State or Country Code	D0
Entity Tax Identification Number	98-0141974
Entity Address, Address Line One	Renaissance House
Entity Address, Address Line Two	12 Crow Lane
Entity Address, City or Town	Pembroke
Entity Address, Postal Zip Code	HM 19
Entity Address, Country	BM
City Area Code	441
Local Phone Number	295-4513
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
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 Public Float			$ 7.7
Entity Common Stock, Shares Outstanding (in shares)		44,148,116
Entity Central Index Key	0000913144
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement for the 2020 Annual General Meeting of Shareholders are incorporated by reference into Part III of this report.
Common Shares, Par Value $1.00 per share
Entity Information [Line Items]
Title of 12(b) Security	Common Shares, Par Value $1.00 per share
Trading Symbol	RNR
Security Exchange Name	NYSE
Series C 6.08% Preference Shares, Par Value $1.00 per share
Entity Information [Line Items]
Title of 12(b) Security	Series C 6.08% Preference Shares, Par Value $1.00 per share
Trading Symbol	RNR PRC
Security Exchange Name	NYSE
Series E 5.375% Preference Shares, Par Value $1.00 per share
Entity Information [Line Items]
Title of 12(b) Security	Series E 5.375% Preference Shares, Par Value $1.00 per share
Trading Symbol	RNR PRE
Security Exchange Name	NYSE
Depositary Shares, each representing a 1/1,000th interest in a Series F 5.750% Preference Share, Par Value $1.00 per share
Entity Information [Line Items]
Title of 12(b) Security	Depositary Shares, each representing a 1/1,000th interest in a Series F 5.750% Preference Share, Par Value $1.00 per share
Trading Symbol	RNR PRF
Security Exchange Name	NYSE

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets
Fixed maturity investments trading, at fair value - amortized cost $11,067,414 at December 31, 2019 (2018 - $8,163,962) (Notes 5 and 6)	$ 11,171,655	$ 8,088,870
Short term investments, at fair value (Notes 5 and 6)	4,566,277	2,586,520
Equity investments trading, at fair value (Notes 5 and 6)	436,931	310,252
Other investments, at fair value (Notes 5 and 6)	1,087,377	784,933
Investments in other ventures, under equity method (Note 5)	106,549	115,172
Total investments	17,368,789	11,885,747
Cash and cash equivalents	1,379,068	1,107,922
Premiums receivable	2,599,896	1,537,188
Prepaid reinsurance premiums (Note 7)	767,781	616,185
Reinsurance recoverable (Notes 7 and 8)	2,791,297	2,372,221
Accrued investment income	72,461	51,311
Deferred acquisition costs and value of business acquired	663,991	476,661
Receivable for investments sold	78,369	256,416
Other assets	346,216	135,127
Goodwill and other intangible assets (Note 4)	262,226	237,418
Total assets	26,330,094	18,676,196
Liabilities
Reserve for claims and claim expenses (Note 8)	9,384,349	6,076,271
Unearned premiums	2,530,975	1,716,021
Debt (Note 9)	1,384,105	991,127
Reinsurance balances payable	2,830,691	1,902,056
Payable for investments purchased	225,275	380,332
Other liabilities	932,024	513,609
Total liabilities	17,287,419	11,579,416
Commitments and Contingencies (Note 20)
Redeemable noncontrolling interests (Note 10)	3,071,308	2,051,700
Shareholders’ Equity (Note 12)
Preference shares: $1.00 par value – 16,010,000 shares issued and outstanding at December 31, 2019 (2018 – 16,010,000)	650,000	650,000
Common shares: $1.00 par value – 44,148,116 shares issued and outstanding at December 31, 2019 (2018 – 42,207,390)	44,148	42,207
Additional paid-in capital	568,277	296,099
Accumulated other comprehensive loss	(1,939)	(1,433)
Retained earnings	4,710,881	4,058,207
Total shareholders’ equity attributable to RenaissanceRe	5,971,367	5,045,080
Total liabilities, noncontrolling interests and shareholders’ equity	$ 26,330,094	$ 18,676,196

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Fixed maturity investments trading, amortized cost	$ 11,067,414	$ 8,163,962
Preference shares, par value (in usd per share)	$ 1	$ 1
Preference shares, shares issued (in shares)	16,010,000	16,010,000
Preference shares, shares outstanding (in shares)	16,010,000	16,010,000
Common shares, par value (in usd per share)	$ 1	$ 1
Common shares, shares issued (in shares)	44,148,116	42,207,390
Common shares, shares outstanding (in shares)	44,148,116	42,207,390

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues
Gross premiums written	$ 905,479	$ 861,068	$ 1,476,908	$ 1,564,295	$ 547,755	$ 625,677	$ 977,343	$ 1,159,652	$ 4,807,750	$ 3,310,427	$ 2,797,540
Net premiums written (Note 7)	725,367	704,130	1,022,965	929,031	411,094	453,255	604,509	663,044	3,381,493	2,131,902	1,871,325
Increase in unearned premiums	244,758	202,618	(111,463)	(379,003)	163,519	78,594	(175,124)	(222,762)	(43,090)	(155,773)	(153,750)
Net premiums earned (Note 7)	970,125	906,748	911,502	550,028	574,613	531,849	429,385	440,282	3,338,403	1,976,129	1,717,575
Net investment income (Note 5)	112,695	113,844	115,832	81,462	53,338	80,696	71,356	56,476	423,833	261,866	222,209
Net foreign exchange (losses) gains	(1,126)	(8,275)	9,309	(2,846)	(932)	(4,566)	(10,687)	3,757	(2,938)	(12,428)	10,628
Equity in earnings of other ventures (Note 5)	5,874	5,877	6,812	4,661	4,143	7,648	5,826	857	23,224	18,474	8,030
Other income	(160)	1,016	922	3,171	5,489	497	1,225	(1,242)	4,949	5,969	9,415
Net realized and unrealized gains (losses) on investments (Note 5)	17,897	31,938	194,003	170,645	(88,654)	13,630	(17,901)	(82,144)	414,483	(175,069)	135,822
Total revenues	1,105,305	1,051,148	1,238,380	807,121	547,997	629,754	479,204	417,986	4,201,954	2,074,941	2,103,679
Expenses
Net claims and claim expenses incurred (Notes 7 and 8)	762,093	654,520	453,373	227,035	477,638	410,510	60,167	171,703	2,097,021	1,120,018	1,861,428
Acquisition expenses	208,618	202,181	227,482	123,951	120,465	109,761	105,052	97,711	762,232	432,989	346,892
Operational expenses	64,571	53,415	59,814	44,933	58,859	40,593	37,543	41,272	222,733	178,267	160,778
Corporate expenses	17,642	13,844	23,847	38,789	12,108	6,841	8,301	6,733	94,122	33,983	18,572
Interest expense (Note 9)	15,496	15,580	15,534	11,754	11,765	11,769	11,768	11,767	58,364	47,069	44,193
Total expenses	1,068,420	939,540	780,050	446,462	680,835	579,474	222,831	329,186	3,234,472	1,812,326	2,431,863
Income (loss) before taxes	36,885	111,608	458,330	360,659	(132,838)	50,280	256,373	88,800	967,482	262,615	(328,184)
Income tax (expense) benefit (Note 15)	3,455	(3,664)	(9,475)	(7,531)	8,852	(1,451)	(4,506)	3,407	(17,215)	6,302	(26,487)
Net income (loss)	40,340	107,944	448,855	353,128	(123,986)	48,829	251,867	92,207	950,267	268,917	(354,671)
Net (income) loss attributable to redeemable noncontrolling interests (Note 10)	2,622	(62,057)	(71,812)	(70,222)	49,269	(6,440)	(54,483)	(29,899)	(201,469)	(41,553)	132,282
Net income (loss) attributable to RenaissanceRe	42,962	45,887	377,043	282,906	(74,717)	42,389	197,384	62,308	748,798	227,364	(222,389)
Dividends on preference shares	(9,189)	(9,189)	(9,189)	(9,189)	(9,189)	(9,708)	(5,596)	(5,595)	(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders	$ 33,773	$ 36,698	$ 367,854	$ 273,717	$ (83,906)	$ 32,681	$ 191,788	$ 56,713	$ 712,042	$ 197,276	$ (244,770)
Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – basic (Note 12) (in usd per share)	$ 0.77	$ 0.83	$ 8.36	$ 6.43	$ (2.10)	$ 0.82	$ 4.78	$ 1.42	$ 16.32	$ 4.91	$ (6.15)
Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – diluted (Note 12) (in usd per share)	$ 0.77	$ 0.83	$ 8.35	$ 6.43	$ (2.10)	$ 0.82	$ 4.78	$ 1.42	$ 16.29	$ 4.91	$ (6.15)

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Comprehensive income (loss)
Net income (loss)	$ 950,267	$ 268,917	$ (354,671)
Change in net unrealized gains on investments, net of tax	2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax	(2,679)	0	0
Comprehensive income (loss)	949,761	267,260	(355,580)
Net (income) loss attributable to redeemable noncontrolling interests	(201,469)	(41,553)	132,282
Comprehensive (income) loss attributable to redeemable noncontrolling interests	(201,469)	(41,553)	132,282
Comprehensive income (loss) attributable to RenaissanceRe	748,292	225,707	(223,298)
Disclosure regarding net unrealized gains (losses)
Total net realized and unrealized holding gains (losses) on investments	2,173	(1,657)	(909)
Change in net unrealized (losses) gains on investments	$ 2,173	$ (1,657)	$ (909)

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Preference shares	Common shares	Additional paid-in capital	Accumulated other comprehensive (loss) income	Retained earnings
Beginning balance at Dec. 31, 2016		$ 400,000	$ 41,187	$ 216,558	$ 1,133	$ 4,207,699
Statement of Changes in Stockholders' Equity
Repurchase of shares			(1,322)	(187,269)
Change in redeemable noncontrolling interest				119
Exercise of options and issuance of restricted stock awards (Notes 12 and 17)			159	7,947
Change in net unrealized gains on investments, net of tax	$ (909)				(909)
Foreign currency translation adjustments, net of tax	0
Net income (loss)	(354,671)					(354,671)
Net (income) loss attributable to redeemable noncontrolling interests (Note 10)	132,282					132,282
Dividends on common shares	(51,400)					(51,370)
Dividends on preference shares	(22,381)					(22,381)
Ending balance at Dec. 31, 2017	4,391,375	400,000	40,024	37,355	224	3,913,772
Statement of Changes in Stockholders' Equity
Issuance of shares (Note 12)		250,000	1,947	248,053
Offering expenses				(8,552)
Change in redeemable noncontrolling interest				837
Exercise of options and issuance of restricted stock awards (Notes 12 and 17)			236	18,406
Change in net unrealized gains on investments, net of tax	(1,657)				(1,657)
Foreign currency translation adjustments, net of tax	0				0
Net income (loss)	268,917					268,917
Net (income) loss attributable to redeemable noncontrolling interests (Note 10)	(41,553)					(41,553)
Dividends on common shares	(52,800)					(52,841)
Dividends on preference shares	(30,088)					(30,088)
Ending balance at Dec. 31, 2018	5,045,080	650,000	42,207	296,099	(1,433)	4,058,207
Statement of Changes in Stockholders' Equity
Issuance of shares (Note 12)			1,739	248,259
Change in redeemable noncontrolling interest				(342)
Exercise of options and issuance of restricted stock awards (Notes 12 and 17)			202	24,261
Change in net unrealized gains on investments, net of tax	2,173				2,173
Foreign currency translation adjustments, net of tax	(2,679)				(2,679)
Net income (loss)	950,267					950,267
Net (income) loss attributable to redeemable noncontrolling interests (Note 10)	(201,469)					(201,469)
Dividends on common shares	(59,400)					(59,368)
Dividends on preference shares	(36,756)
Ending balance at Dec. 31, 2019	$ 5,971,367	$ 650,000	$ 44,148	$ 568,277	$ (1,939)	$ 4,710,881

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows provided by operating activities
Net income (loss)	$ 950,267	$ 268,917	$ (354,671)
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Amortization, accretion and depreciation	(58,964)	123	31,242
Equity in undistributed (earnings) losses of other ventures	(762)	(3,772)	6,295
Net realized and unrealized (gains) losses on investments	(414,483)	175,069	(135,822)
Net unrealized (gains) losses included in net investment income	(12,221)	8,309	(24,737)
Change in:
Premiums receivable	(424,973)	(232,566)	(317,299)
Prepaid reinsurance premiums	(11,798)	(82,639)	(92,286)
Reinsurance recoverable	129,665	(785,591)	(1,307,066)
Deferred acquisition costs	118,676	(50,110)	(91,226)
Reserve for claims and claim expenses	900,562	995,863	2,232,114
Unearned premiums	51,343	238,412	246,036
Reinsurance balances payable	658,532	912,966	315,107
Other	251,351	(223,280)	518,100
Net cash provided by operating activities	2,137,195	1,221,701	1,025,787
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	17,313,940	11,585,576	9,490,669
Purchases of fixed maturity investments trading	(17,919,343)	(12,489,972)	(10,093,532)
Net (purchases) sales of equity investments trading	(7,841)	14,156	115,837
Net (purchases) sales of short term investments	(1,900,741)	(1,436,389)	364,011
Net purchases of other investments	(202,878)	(199,475)	(19,419)
Net purchases of investments in other ventures	(2,717)	(21,473)	0
Return of investment from investment in other ventures	11,250	8,464	20,000
Net (purchases) sales of other assets	(4,108)	2,500	0
Net purchase of TMR	(276,206)	0	0
Net cash used in investing activities	(2,988,644)	(2,536,613)	(122,434)
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares	(59,368)	(52,841)	(51,370)
Dividends paid – preference shares	(36,756)	(30,088)	(22,381)
RenaissanceRe common share repurchases	0	0	(188,591)
RenaissanceRe common share issuance	0	250,000	0
Issuance of debt, net of expenses	396,411	0	295,866
Repayment of debt	0	0	(250,000)
Issuance of preference shares, net of expenses	0	241,448	0
Net third-party redeemable noncontrolling interest share transactions	827,083	665,683	260,475
Taxes paid on withholding shares	(7,253)	(7,862)	(15,139)
Net cash provided by financing activities	1,120,117	1,066,340	28,860
Effect of exchange rate changes on foreign currency cash	2,478	(5,098)	8,222
Net increase (decrease) in cash and cash equivalents	271,146	(253,670)	940,435
Cash and cash equivalents, beginning of year	1,107,922	1,361,592	421,157
Cash and cash equivalents, end of year	1,379,068	1,107,922	1,361,592
Supplemental Cash Flow Information
Income taxes paid	9,749	341	343
Interest paid	$ 53,220	$ 45,623	$ 44,171

Organization

Organization	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	ORGANIZATION RenaissanceRe Holdings Ltd. (“RenaissanceRe” or the “Company”) was formed under the laws of Bermuda on June 7, 1993. Together with its wholly owned and majority-owned subsidiaries and joint ventures, the Company provides property, casualty and specialty reinsurance and certain insurance solutions to its customers. • On March 22, 2019, the Company’s wholly owned subsidiary, RenaissanceRe Specialty Holdings (UK) Limited (“RenaissanceRe Specialty Holdings”), completed its previously announced purchase of all of the share capital of RenaissanceRe Europe AG (formerly known as Tokio Millennium Re AG) (“RenaissanceRe Europe”), RenaissanceRe (UK) Limited (formerly known as Tokio Millennium Re (UK) Limited) (“RenaissanceRe UK”), and their respective subsidiaries (collectively, “TMR”) pursuant to a Stock Purchase Agreement by and among the Company, Tokio Marine & Nichido Fire Insurance Co. Ltd. (“Tokio”) and, with respect to certain sections only, Tokio Marine Holdings, Inc. entered into on October 30, 2018 (the “TMR Stock Purchase Agreement”) (the “TMR Stock Purchase”). TMR comprised the treaty reinsurance business of Tokio Marine Holdings, Inc. The results of operations of TMR from March 22, 2019, through December 31, 2019, are reflected in the Company’s results of operations for the year ended December 31, 2019. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information regarding the TMR Stock Purchase. • Renaissance Reinsurance Ltd. (“Renaissance Reinsurance”), a Bermuda-domiciled reinsurance company, is the Company’s principal reinsurance subsidiary and provides property, casualty and specialty reinsurance coverages to insurers and reinsurers on a worldwide basis. • Renaissance Reinsurance U.S. Inc. (“Renaissance Reinsurance U.S.”) is a reinsurance company domiciled in the state of Maryland that provides property, casualty and specialty reinsurance coverages to insurers and reinsurers, primarily in the Americas. • RenaissanceRe Underwriting Managers U.S. LLC, a specialty reinsurance agency domiciled in the state of Connecticut, provides specialty treaty reinsurance solutions on both a quota share and excess of loss basis; and writes business on behalf of RenaissanceRe Specialty U.S. Ltd. (“RenaissanceRe Specialty U.S.”), a Bermuda-domiciled reinsurer, which operates subject to U.S. federal income tax, and RenaissanceRe Syndicate 1458 (“Syndicate 1458”). • Syndicate 1458 is the Company’s Lloyd’s syndicate. RenaissanceRe Corporate Capital (UK) Limited (“RenaissanceRe CCL”), a wholly owned subsidiary of RenaissanceRe, is Syndicate 1458’s sole corporate member. RenaissanceRe Syndicate Management Ltd. (“RSML”), a wholly owned subsidiary of RenaissanceRe, is the managing agent for Syndicate 1458. • RenaissanceRe Europe, a Swiss-domiciled reinsurance company, which has branches in Australia, Bermuda, the U.K. and the U.S., provides property, casualty and specialty reinsurance coverages to insurers and reinsurers on a worldwide basis. • RenaissanceRe UK, a U.K.-domiciled reinsurance company in run-off, provided property, casualty and specialty reinsurance coverages on a worldwide basis. RenaissanceRe UK was placed into run-off effective July 1, 2015, from which date all new and renewal business was written by the U.K. branch of RenaissanceRe Europe. On February 4, 2020, RenaissanceRe Specialty Holdings entered into an agreement to sell RenaissanceRe UK to an investment vehicle managed by AXA Liabilities Managers, an affiliate of AXA XL. The sale is expected to close in 2020 and is subject to regulatory approval. • The Company also manages property, casualty and specialty reinsurance business written on behalf of joint ventures, which include Top Layer Reinsurance Ltd. (“Top Layer Re”), recorded under the equity method of accounting, and DaVinci Reinsurance Ltd. (“DaVinci”). Because the Company owns a noncontrolling equity interest in, but controls a majority of the outstanding voting power of DaVinci’s parent, DaVinciRe Holdings Ltd. (“DaVinciRe”), the results of DaVinci and DaVinciRe are consolidated in the Company’s consolidated financial statements and all significant intercompany transactions have been eliminated. Redeemable noncontrolling interest - DaVinciRe represents the interests of external parties with respect to the net income and shareholders’ equity of DaVinciRe. Renaissance Underwriting Managers, Ltd. (“RUM”), a wholly owned subsidiary of RenaissanceRe, acts as exclusive underwriting manager for these joint ventures in return for fee-based income and profit participation. • RenaissanceRe Medici Fund Ltd. (“Medici”) is an exempted fund, incorporated under the laws of Bermuda. Medici’s objective is to seek to invest substantially all of its assets in various insurance-based investment instruments that have returns primarily tied to property catastrophe risk. Third-party investors have subscribed for a portion of the participating, non-voting common shares of Medici. Because the Company owns a noncontrolling equity interest in, but controls a majority of the outstanding voting power of Medici, through its wholly-owned parent, RenaissanceRe Fund Holdings Ltd. (“Fund Holdings”), the results of Medici and Fund Holdings are consolidated in the Company’s consolidated financial statements and all significant inter-company transactions have been eliminated. Redeemable noncontrolling interest - Medici represents the interests of external parties with respect to the net income and shareholders’ equity of Medici. • Upsilon RFO Re Ltd., formerly known as Upsilon Reinsurance II Ltd. (“Upsilon RFO”), a Bermuda domiciled special purpose insurer (“SPI”), is a managed joint venture formed by the Company principally to provide additional capacity to the worldwide aggregate and per-occurrence primary and retrocessional property catastrophe excess of loss market. Upsilon RFO is considered a variable interest entity (“VIE”) and the Company is considered the primary beneficiary. As a result, Upsilon RFO is consolidated by the Company and all significant inter-company transactions have been eliminated. • RenaissanceRe Upsilon Fund Ltd. (“Upsilon Fund”), an exempted Bermuda segregated accounts company was formed by the Company to provide a fund structure through which third-party investors can invest in reinsurance risk managed by the Company. As a segregated accounts company, Upsilon Fund is permitted to establish segregated accounts to invest in and hold identified pools of assets and liabilities. Each pool of assets and liabilities in each segregated account is structured to be ring-fenced from any claims from the creditors of Upsilon Fund’s general account and from the creditors of other segregated accounts within Upsilon Fund. Third-party investors purchase redeemable, non-voting preference shares linked to specific segregated accounts of Upsilon Fund and own 100% of these shares. Upsilon Fund is an investment company and is considered a VIE. The Company is not considered the primary beneficiary of Upsilon Fund and, as a result, the Company does not consolidate the financial position and results of operations of Upsilon Fund. • Effective December 17, 2018, the Company formed Vermeer Reinsurance Ltd. (“Vermeer”), an exempted Bermuda reinsurer, with PGGM, a Dutch pension fund manager. Vermeer provides capacity focused on risk remote layers in the U.S. property catastrophe market. Vermeer is managed by RUM in return for a management fee. The Company maintains a majority voting control of Vermeer, while PGGM retains economic benefits. Vermeer is considered a VIE, as it has voting rights that are not proportional to its participating rights and the Company is the primary beneficiary. As a result, the Company consolidates Vermeer and all significant inter-company transactions have been eliminated. The Company does not currently expect its voting or economic interest in Vermeer to fluctuate. • Fibonacci Reinsurance Ltd. ("Fibonacci Re"), a Bermuda-domiciled SPI, was formed in 2016 to provide collateralized capacity to Renaissance Reinsurance and its affiliates. Fibonacci Re raises capital from third-party investors and the Company, via private placements of participating notes which are listed on the Bermuda Stock Exchange. Fibonacci Re is considered a VIE. The Company is not considered the primary beneficiary of Fibonacci Re and, as a result, the Company does not consolidate the financial position and results of operations of Fibonacci Re. • Effective December 22, 2017, the Company and Reinsurance Group of America, Incorporated closed an initiative (“Langhorne”) to source third-party capital to support reinsurers targeting large in-force life and annuity blocks. Langhorne Holdings LLC (“Langhorne Holdings”) is a company that owns and manages certain reinsurance entities within Langhorne. Langhorne Partners LLC (“Langhorne Partners”) is the general partner for Langhorne and the entity which manages the third-parties investing in Langhorne Holdings. The Company concluded that Langhorne Holdings meets the definition of a VIE. The Company is not the primary beneficiary of Langhorne Holdings and as a result, the Company does not consolidate the financial position or results of operations of Langhorne Holdings. The Company concluded that Langhorne Partners is not a VIE. The Company will account for its investments in Langhorne Holdings and Langhorne Partners under the equity method of accounting, one quarter in arrears. • In connection with the acquisition of TMR, the Company manages Shima Reinsurance Ltd. (“Shima Re”), Norwood Re Ltd. (“Norwood Re”) and Blizzard Re Ltd. (“Blizzard Re”) (together, the “TMR managed third-party capital vehicles”), which provide third-party investors with access to reinsurance risk formerly managed by TMR. Following the closing of the acquisition, the retrocessionaires providing reinsurance to TMR on certain TMR managed third-party capital vehicles’ legacy portfolios of in-force and expired contracts were replaced. The TMR managed third-party capital vehicles no longer write new business.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Significant Accounting Policies	SIGNIFICANT ACCOUNTING POLICIES BASIS OF PRESENTATION These consolidated financial statements have been prepared on the basis of accounting principles generally accepted in the United States (“GAAP”). All significant intercompany accounts and transactions have been eliminated from these statements. Certain comparative information has been reclassified to conform to the current presentation. USE OF ESTIMATES IN FINANCIAL STATEMENTS The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported and disclosed amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates. The major estimates reflected in the Company’s consolidated financial statements include, but are not limited to, the reserve for claims and claim expenses; reinsurance recoverables, including allowances for reinsurance recoverables deemed uncollectible; estimates of written and earned premiums; fair value, including the fair value of investments, financial instruments and derivatives; impairment charges; deferred acquisition costs and the value of business acquired (“VOBA”) and the Company’s deferred tax valuation allowance. PREMIUMS AND RELATED EXPENSES Premiums are recognized as income, net of any applicable reinsurance or retrocessional coverage purchased, over the terms of the related contracts and policies. Premiums written are based on contract and policy terms and include estimates based on information received from both insureds and ceding companies. Subsequent differences arising on such estimates are recorded in the period in which they are determined. Unearned premiums represent the portion of premiums written that relate to the unexpired terms of contracts and policies in force. Amounts are computed by pro rata methods based on statistical data or reports received from ceding companies. Reinstatement premiums are estimated after the occurrence of a significant loss and are recorded in accordance with the contract terms based upon paid losses and case reserves. Reinstatement premiums are earned when written. Acquisition costs are incurred when a contract or policy is issued and only the costs directly related to the successful acquisition of new and renewal contract or policies are deferred and amortized over the same period in which the related premiums are earned. Acquisition costs consist principally of commissions, brokerage and premium tax expenses. Certain of our assumed contracts contain profit sharing provisions or adjustable commissions that are estimated based on the expected loss and loss adjustment expense on those contracts. Acquisition costs include accruals for such estimates of commissions and are shown net of commissions and profit commissions earned on ceded reinsurance. Deferred policy acquisition costs are limited to their estimated realizable value based on the related unearned premiums. Anticipated claims and claim expenses, based on historical and current experience, and anticipated investment income related to those premiums are considered in determining the recoverability of deferred acquisition costs. CLAIMS AND CLAIM EXPENSES The reserve for claims and claim expenses includes estimates for unpaid claims and claim expenses on reported losses as well as an estimate of losses incurred but not reported. The reserve is based on individual claims, case reserves and other reserve estimates reported by insureds and ceding companies as well as management estimates of ultimate losses. Inherent in the estimates of ultimate losses are expected trends in claim severity and frequency and other factors which could vary significantly as claims are settled. Also, during the past few years, the Company has increased its casualty and specialty reinsurance businesses, but does not have the benefit of a significant amount of its own historical experience in certain of these lines of business. Accordingly, the reserving for incurred losses in these lines of business could be subject to greater variability. Ultimate losses may vary materially from the amounts provided in the consolidated financial statements. These estimates are reviewed regularly and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments, if any, are reflected in the consolidated statements of operations in the period in which they become known and are accounted for as changes in estimates. REINSURANCE Amounts recoverable from reinsurers are estimated in a manner consistent with the claim liability associated with the reinsured policies. For multi-year retrospectively rated contracts, the Company accrues amounts (either assets or liabilities) that are due to or from assuming companies based on estimated contract experience. If the Company determines that adjustments to earlier estimates are appropriate, such adjustments are recorded in the period in which they are determined. Reinsurance recoverables on dual trigger reinsurance contracts require the Company to estimate its ultimate losses applicable to these contracts as well as estimate the ultimate amount of insured industry losses that will be reported by the applicable statistical reporting agency, as per the contract terms. Amounts recoverable from reinsurers are recorded net of a valuation allowance for estimated uncollectible recoveries. Assumed and ceded reinsurance contracts that lack a significant transfer of risk are treated as deposits. Certain assumed and ceded reinsurance contracts that do not meet all of the criteria to be accounted for as reinsurance in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic Financial Services - Insurance have been accounted for at fair value under the fair value option in accordance with FASB ASC Topic Financial Instruments. INVESTMENTS, CASH AND CASH EQUIVALENTS Fixed Maturity Investments Investments in fixed maturities are classified as trading and are reported at fair value. Investment transactions are recorded on the trade date with balances pending settlement reflected in the balance sheet as a receivable for investments sold or a payable for investments purchased. Net investment income includes interest and dividend income together with amortization of market premiums and discounts and is net of investment management and custody fees. The amortization of premium and accretion of discount for fixed maturity securities is computed using the effective yield method. For mortgage-backed securities and other holdings for which there is prepayment risk, prepayment assumptions are evaluated quarterly and revised as necessary. Any adjustments required due to the change in effective yields and maturities are recognized on a prospective basis through yield adjustments. Fair values of investments are based on quoted market prices, or when such prices are not available, by reference to broker or underwriter bid indications and/or internal pricing valuation techniques. The net unrealized appreciation or depreciation on fixed maturity investments trading is included in net realized and unrealized gains (losses) on investments in the consolidated statements of operations. Realized gains or losses on the sale of investments are determined on the basis of the first in first out cost method. Short Term Investments Short term investments, which are managed as part of the Company’s investment portfolio and have a maturity of one year or less when purchased, are carried at fair value. The net unrealized appreciation or depreciation on short term investments is included in net realized and unrealized gains on investments in the consolidated statements of operations. Equity Investments, Classified as Trading Equity investments are accounted for at fair value in accordance with FASB ASC Topic Financial Instruments. Fair values are primarily priced by pricing services, reflecting the closing price quoted for the final trading day of the period. Net investment income includes dividend income and the net realized and unrealized appreciation or depreciation on equity investments is included in net realized and unrealized gains (losses) on investments in the consolidated statements of operations. Other Investments The Company accounts for its other investments at fair value in accordance with FASB ASC Topic Financial Instruments with interest, dividend income, income distributions and realized and unrealized gains and losses included in net investment income. The fair value of certain of the Company’s fund investments, which principally include private equity investments, senior secured bank loan funds and hedge funds, is recorded on its balance sheet in other investments, and is generally established on the basis of the net valuation criteria established by the managers of such investments, if applicable. The net valuation criteria established by the managers of such investments is established in accordance with the governing documents of such investments. Certain of the Company’s fund managers, fund administrators, or both, are unable to provide final fund valuations as of the Company’s current reporting date. The typical reporting lag experienced by the Company to receive a final net asset value report is one month for hedge funds and senior secured bank loan funds and three months for private equity investments, although, in the past, in respect of certain of the Company’s private equity investments, the Company has on occasion experienced delays of up to six months at year end, as the private equity investments typically complete their respective year-end audits before releasing their final net asset value statements. In circumstances where there is a reporting lag between the current period end reporting date and the reporting date of the latest fund valuation, the Company estimates the fair value of these funds by starting with the prior month or quarter-end fund valuations, adjusting these valuations for actual capital calls, redemptions or distributions, as well as the impact of changes in foreign currency exchange rates, and then estimating the return for the current period. In circumstances in which the Company estimates the return for the current period, all information available to the Company is utilized. This principally includes preliminary estimates reported to the Company by its fund managers, obtaining the valuation of underlying portfolio investments where such underlying investments are publicly traded and therefore have a readily observable price, using information that is available to the Company with respect to the underlying investments, reviewing various indices for similar investments or asset classes, as well as estimating returns based on the results of similar types of investments for which the Company has obtained reported results, or other valuation methods, where possible. Actual final fund valuations may differ, perhaps materially so, from the Company’s estimates and these differences are recorded in the Company’s statement of operations in the period in which they are reported to the Company as a change in estimate. The Company’s other investments also include investments in catastrophe bonds which are recorded at fair value and the fair value is based on broker or underwriter bid indications. Investments in Other Ventures, Under Equity Method Investments in which the Company has significant influence over the operating and financial policies of the investee are classified as investments in other ventures, under equity method, and are accounted for under the equity method of accounting. Under this method, the Company records its proportionate share of income or loss from such investments in its results for the period. Any decline in value of investments in other ventures, under equity method considered by management to be other-than-temporary is charged to income in the period in which it is determined. Cash and Cash Equivalents Cash equivalents include money market instruments with a maturity of ninety days or less when purchased. STOCK INCENTIVE COMPENSATION The Company is authorized to issue restricted stock awards and units, performance shares, stock options and other equity-based awards to its employees and directors. The fair value of the compensation cost is measured at the grant date and expensed over the period for which the employee is required to provide services in exchange for the award. In addition, the Company is authorized to issue cash settled restricted stock units (“CSRSU”) to its employees. The fair value of CSRSUs is determined using the fair market value of RenaissanceRe common shares at the end of each reporting period and is expensed over the period for which the employee is required to provide service in exchange for the award. The fair value of these awards is recorded on the Company’s consolidated balance sheet as a liability as it is expensed and until the point payment is made to the employee. The Company has elected to recognize forfeitures as they occur rather than estimating service-based forfeitures over the requisite service period. DERIVATIVES From time to time, the Company enters into derivative instruments such as futures, options, swaps, forward contracts and other derivative contracts primarily to manage its foreign currency exposure, obtain exposure to a particular financial market, for yield enhancement, or for trading and to assume risk. The Company accounts for its derivatives in accordance with FASB ASC Topic Derivatives and Hedging , which requires all derivatives to be recorded at fair value on the Company’s balance sheet as either assets or liabilities, depending on their rights or obligations, with changes in fair value reflected in current earnings. Commencing in 2019, the Company elected to adopt hedge accounting for certain of its derivative instruments used as hedges of a net investment in a foreign operation, as discussed below. The fair value of the Company’s derivatives is estimated by reference to quoted prices or broker quotes, where available, or in the absence of quoted prices or broker quotes, the use of industry or internal valuation models. Hedges of the Net Investment in a Foreign Operation Changes in the fair value of derivative instruments used to hedge the net investment in a foreign operation, to the extent effective as a hedge, are recorded as a component of accumulated other comprehensive income (loss) in foreign currency translation adjustments, net of tax. Cumulative changes in fair value recorded in accumulated other comprehensive income (loss) are reclassified into earnings upon the sale, or complete or substantially complete liquidation, of the foreign operation. Any hedge ineffectiveness is recorded immediately in current period earnings as net foreign exchange gains (losses). Hedge Documentation and Effectiveness Testing To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in value or cash flow of the hedged item. At the inception of a hedge, the Company formally documents relationships between hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking each hedge transaction. The documentation process includes linking derivatives that are designated as net investment hedges to specific assets or liabilities on the consolidated balance sheet. The Company also formally assesses, both at the hedge's inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in the net investment in a foreign operation. The Company will discontinue hedge accounting prospectively if it determines that the derivative is no longer highly effective in offsetting changes in the net investment in a foreign operation, the derivative is no longer designated as a hedging instrument, or the derivative expires or is sold, terminated or exercised. If hedge accounting is discontinued, the derivative continues to be carried at fair value on the consolidated balance sheet with changes in its fair value recognized in current period earnings through net realized and unrealized gains (losses) on investments. FAIR VALUE The Company accounts for certain of its assets and liabilities at fair value in accordance with FASB ASC Topic Fair Value Measurement s and Disclosures . The Company recognizes the change in unrealized gains and losses arising from changes in fair value in its statements of operations. BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS The Company accounts for business combinations in accordance with FASB ASC Topic Business Combinations , and goodwill and other intangible assets that arise from business combinations in accordance with FASB ASC Topic Intangibles – Goodwill and Other . A purchase price that is in excess of the fair value of the net assets acquired arising from a business combination is recorded as goodwill, and is not amortized. Other intangible assets with a finite life are amortized over the estimated useful life of the asset. Other intangible assets with an indefinite useful life are not amortized. Goodwill and other indefinite life intangible assets are tested for impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying amount may not be recoverable. Finite life intangible assets are reviewed for indicators of impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying amount may not be recoverable, and tested for impairment if appropriate. For purposes of the annual impairment evaluation, goodwill is assigned to the applicable reporting unit of the acquired entities giving rise to the goodwill. Goodwill and other intangible assets recorded in connection with investments accounted for under the equity method, are recorded as “Investments in other ventures, under equity method” on the Company’s consolidated balance sheets. The Company has established the beginning of the fourth quarter as the date for performing its annual impairment tests. The Company has the option to first assess qualitative factors to determine whether it is necessary to perform the quantitative goodwill impairment test. Under this option, the Company would not be required to calculate the fair value of a reporting unit unless the Company determines, based on its qualitative assessment, that it is more likely than not that a reporting unit’s fair value is less than its carrying amount. If goodwill or other intangible assets are impaired, they are written down to their estimated fair value with a corresponding expense reflected in the Company’s consolidated statements of operations. The Company initially recorded VOBA to reflect the establishment of the value of business acquired asset, which represents the estimated present value of the expected underwriting profit within the unearned premiums liability, net of reinsurance, less costs to service the related policies and a risk premium. VOBA is derived using, among other things, estimated loss ratios by line of business to calculate the underwriting profit, weighted average cost of capital, risk premium and expected payout patterns. The adjustment for VOBA will be amortized to acquisition expenses over approximately two years , as the contracts for business in-force as of the acquisition date expire. NONCONTROLLING INTERESTS The Company accounts for redeemable noncontrolling interests in the mezzanine section of the Company’s consolidated balance sheet in accordance with United States Securities and Exchange Commission (“SEC”) guidance which is applicable to SEC registrants. The SEC guidance requires shares, not required to be accounted for in accordance with FASB ASC Topic Distinguishing Liabilities from Equity , and having redemption features that are not solely within the control of the issuer, to be classified outside of permanent equity in the mezzanine section of the balance sheet. Because the share classes related to the redeemable noncontrolling interest portion of the issuer are not considered liabilities in accordance with FASB ASC Topic Distinguishing Liabilities from Equity and have redemption features that are not solely within the control of the issuer, the redeemable noncontrolling interests are presented in the mezzanine section on the Company’s consolidated balance sheet in accordance with the SEC guidance noted above. The SEC guidance does not impact the accounting for redeemable noncontrolling interest on the consolidated statements of operations; therefore, the provisions of FASB ASC Topic Consolidation with respect to the consolidated statements of operations still apply, and net income attributable to redeemable noncontrolling interests is presented separately in the Company’s consolidated statements of operations. VARIABLE INTEREST ENTITIES The Company accounts for VIEs in accordance with FASB ASC Topic Consolidation , which requires the consolidation of all VIEs by the primary beneficiary, that being the investor that has the power to direct the activities of the VIE and that will absorb a portion of the VIE’s expected losses or residual returns that could potentially be significant to the VIE. For VIEs the Company determines it has a variable interest in, it determines whether it is the primary beneficiary of a VIE by performing an analysis that principally considers: (i) the VIE’s purpose and design, including the risks the VIE was designed to create and pass through to its variable interest holders; (ii) the VIE’s capital structure; (iii) the terms between the VIE and its variable interest holders and other parties involved with the VIE; (iv) which variable interest holders have the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance; (v) which variable interest holders have the obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE; and (vi) related party relationships. The Company reassesses its initial determination of whether the Company is the primary beneficiary of a VIE upon changes in facts and circumstances that could potentially alter the Company’s assessment. EARNINGS PER SHARE The Company calculates earnings per share in accordance with FASB ASC Topic Earnings per Share. Basic earnings per share are based on weighted average common shares and exclude any dilutive effects of options and restricted stock. Diluted earnings per share assumes the exercise of all dilutive stock options and restricted stock grants. The two-class method is used to determine earnings per share based on dividends declared on common shares and participating securities (i.e., distributed earnings) and participation rights of participating securities in any undistributed earnings. Each unvested restricted share granted by the Company to its employees is considered a participating security and the Company uses the two-class method to calculate its net income available to RenaissanceRe common shareholders per common share – basic and diluted. FOREIGN EXCHANGE Monetary assets and liabilities denominated in a currency other than the functional currency of the Company’s subsidiaries in which those monetary assets and liabilities reside are revalued into such subsidiary’s functional currency at the prevailing exchange rate on the balance sheet date. Revenues and expenses denominated in a currency other than the functional currency of the Company’s subsidiaries, are valued at the exchange rate on the date on which the underlying revenue or expense transaction occurred. The net effect of these revaluation adjustments are recognized in the Company’s consolidated statement of operations as part of net foreign exchange (gains) losses. The Company’s functional currency is the U.S. dollar. Certain of the Company’s subsidiaries have a functional currency other than the U.S. dollar. Assets and liabilities of foreign operations whose functional currency is not the U.S. dollar are translated into the Company's U.S. dollar reporting currency at prevailing balance sheet-date exchange rates, while revenue and expenses of such foreign operations are translated into the Company's U.S. dollar functional currency at monthly average exchange rates during the year. The net effect of these translation adjustments, as well as any gains or losses on intercompany balances for which settlement is not planned or anticipated in the foreseeable future, net of applicable deferred income taxes, is included in the Company’s consolidated balance sheet as currency translation adjustments and reflected within accumulated other comprehensive income (loss). TAXATION Income taxes have been provided for in accordance with the provisions of FASB ASC Topic Income Taxes . Deferred tax assets and liabilities result from temporary differences between the amounts recorded in the consolidated financial statements and the tax basis of the Company’s assets and liabilities. Such temporary differences are primarily due to net operating loss carryforwards and GAAP versus tax basis accounting differences relating to interest expense, underwriting results, accrued expenses and investments. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance against deferred tax assets is recorded if it is more likely than not that all, or some portion, of the benefits related to deferred tax assets will not be realized. Uncertain tax positions are also accounted for in accordance with FASB ASC Topic Income Taxes . Uncertain tax positions must meet a more likely than not recognition threshold to be recognized. RECENTLY ADOPTED ACCOUNTING PRONOUNCEMENTS Leases In February 2016, the FASB issued Accounting Standards Update (“ASU”) No. 2016-02, Leases and subsequently issued a number of other ASUs to amend the guidance, each ultimately reflected in FASB ASC Topic Leases . FASB ASC Topic Leases requires, among other items, lessees to recognize lease assets and lease liabilities on the balance sheet for those leases classified as operating leases under the previous guidance. FASB ASC Topic Leases was effective for public business entities for annual and interim periods beginning after December 15, 2018. The Company has adopted FASB ASC Topic Leases through the application of the modified retrospective transition approach. In addition, the Company employed certain practical expedients permitted under the guidance and utilized its incremental borrowing rate in determining the present value of lease payments, not yet paid. The adoption of this guidance did not have a material impact on the Company’s consolidated statements of operations and financial position. The Company determined there was no material impact and as a result, there was no cumulative effect adjustment to opening retained earnings as of January 1, 2019. Intra-Entity Transfers of Assets Other Than Inventory In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Transfers of Assets Other Than Inventory (“ASU 2016-16”). ASU 2016-16 requires entities to recognize the income tax consequences of intra-entity transfers of assets other than inventory when the transfers occur; this is a change from current guidance which prohibits the recognition of current and deferred income taxes until the underlying assets have been sold to outside entities. ASU 2016-16 was effective for public business entities for annual and interim periods beginning after December 15, 2018. The adoption of this guidance did not have a material impact on the Company’s consolidated statements of operations and financial position. Improvements to Employee Share-Based Payment Accounting In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”). ASU 2016-09 was issued to simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, treatment of forfeitures, classification of awards as either equity or liabilities, and the classification of taxes paid on the statements of cash flows. ASU 2016-09 became effective for the Company in annual and interim periods beginning after December 15, 2016. The cumulative effect of the adoption of ASU 2016-09 was a $2.2 million increase to opening retained earnings as of January 1, 2017. Revenue from Contracts with Customers In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). ASU 2014-09 provides comprehensive guidance on the recognition of revenue from customers arising from the transfer of goods and services. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 also provides guidance on accounting for certain contract costs and had also required new disclosures. ASU 2014-09 was to be effective for public business entities in annual and interim periods beginning after December 15, 2016, however in July 2015, the FASB decided to defer by one year the effective dates of ASU 2014-09, and as a result, ASU 2014-09 is effective for public business entities in annual and interim periods beginning after December 15, 2017. ASU 2014-09 notably excludes the accounting for insurance contracts, leases, financial instruments and guarantees. As a result, the Company’s implementation efforts primarily focused on other income and operational expenses on its consolidated statements of operations. The adoption of ASU 2014-09 did not have a material impact on the Company’s consolidated statements of operations and financial position. Recognition and Measurement of Financial Assets and Financial Liabilities In January 2016, the FASB issued ASU No. 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU 2016-01”). ASU 2016-01 requires equity investments (except those accounted for under the equity method of accounting or those that result in the consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income, simplifies the impairment assessment of equity investments without readily determinable values by requiring a qualitative assessment to identify impairment, eliminates the requirement to disclose the methods and significant assumptions used to estimate the fair value for financial instruments measured at amortized cost, requires the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes, requires separate presentation in other comprehensive income of the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the organization has elected to measure the liabilities in accordance with the fair value option, requires the separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the accompanying notes to the financial statements and clarifies that the reporting organization should evaluate the need for a valuation allowance on a deferred tax asset related to available for sale securities in combination with the organization’s other deferred tax assets. ASU 2016-01 is effective for public business entities in annual and interim periods beginning after December 15, 2017. The adoption of ASU 2016-01 did not have a material impact on the Company’s consolidated statements of operations and financial position. Classification of Certain Cash Receipts and Cash Payments In August 2016, the FASB issued ASU No. 2016-15, Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”). ASU 2016-15 clarifies the classification of receipts and payments in the statement of cash flows. ASU 2016-15 provides guidance related to (1) settlement and payment of zero coupon debt instruments, (2) contingent consideration, (3) proceeds from settlement of insurance claims, (4) proceeds from settlement of corporate and bank owned life insurance policies, (5) distributions from equity method

Acquisition of Tokio Millennium

Acquisition of Tokio Millennium Re	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Acquisition of Tokio Millennium Re	ACQUISITION OF TOKIO MILLENNIUM RE Overview The aggregate consideration for the TMR Stock Purchase, which closed on March 22, 2019, was $1.6 billion , consisting of cash, RenaissanceRe common shares and a special dividend from TMR, as described in more detail below. The aggregate consideration paid at closing for the TMR Stock Purchase was based on the closing tangible book value of TMR, subject to a post-closing adjustment under the terms of the TMR Stock Purchase Agreement. The parties determined that no closing adjustment was required. In connection with the closing of the TMR Stock Purchase, Tokio, RenaissanceRe Europe and RenaissanceRe UK entered into a reserve development agreement whereby RenaissanceRe Europe and RenaissanceRe UK agreed to cede to Tokio, and Tokio agreed to indemnify and reimburse RenaissanceRe Europe and RenaissanceRe UK for, substantially all of RenaissanceRe Europe and RenaissanceRe UK’s adverse development on stated reserves at time of the closing, including unearned premium reserves, subject to certain terms and conditions. The reserve development agreement provides the Company with indemnification on stated reserves, including unearned premium reserves, for RenaissanceRe Europe and RenaissanceRe UK, on a whole-account basis, and takes into consideration adverse performance across the Company’s reportable segments. To the extent the combined performance of acquired reserves for claims and claim expenses or unearned premiums is worse than expected on an aggregate basis across reportable segments, the Company is indemnified under the terms of the reserve development agreement and would expect to collect under the reserve development agreement. At closing, RenaissanceRe Europe and Tokio entered into a retrocessional agreement pursuant to which RenaissanceRe Europe ceded to Tokio all of its liabilities arising from certain stop loss reinsurance contracts RenaissanceRe Europe entered into with third-party capital partners which were either in force as of the closing date or which incept prior to December 31, 2021. The Company recorded $49.7 million of corporate expenses associated with the acquisition of TMR during 2019 ( 2018 - $3.4 million ). Included in these expenses are compensation, transaction and integration-related costs. Purchase Price The Company's total purchase price for TMR was calculated as follows: Special Dividend Special Dividend paid to common shareholders of Tokio and holders of Tokio equity awards $ 500,000 RenaissanceRe common shares Common shares issued by RenaissanceRe to Tokio 1,739,071 Common share price of RenaissanceRe (1) $ 143.75 Market value of RenaissanceRe common shares issued by RenaissanceRe to Tokio 249,998 Cash consideration Cash consideration paid by RenaissanceRe as acquisition consideration 813,595 Total purchase price 1,563,593 Less: Special Dividend paid to Tokio (500,000 ) Net purchase price $ 1,063,593 (1) RenaissanceRe common share price was based on the 30 -day trailing volume weighted average price of $143.7539 as of market close on March 15, 2019, which approximates fair value. Fair Value of Net Assets Acquired and Liabilities Assumed The purchase price was allocated to the acquired assets and liabilities of the Company based on estimated fair values on March 22, 2019, the date the transaction closed, as detailed below. During the quarter ended March 31, 2019, the Company recognized goodwill of $13.1 million , based on foreign exchange rates on March 22, 2019, attributable to the excess of the purchase price over the fair value of the net assets of TMR. The Company recognized identifiable finite lived intangible assets of $11.2 million , which will be amortized over a weighted average period of 10.5 years , identifiable indefinite lived intangible assets of $6.8 million , and certain other adjustments to the fair values of the assets acquired, liabilities assumed and shareholders’ equity of TMR at March 22, 2019, based on foreign exchange rates on March 22, 2019, as summarized in the table below: Shareholders’ equity of TMR at March 22, 2019 $ 1,032,961 Adjustments for fair value, by applicable balance sheet caption: Net deferred acquisition costs and value of business acquired (56,788 ) Net reserve for claims and claim expenses 67,782 Goodwill and intangible assets at March 22, 2019 of TMR (6,569 ) Total adjustments for fair value by applicable balance sheet caption before tax impact 4,425 Other assets - net deferred tax liability related to fair value adjustments and value of business acquired (2,606 ) Total adjustments for fair value by applicable balance sheet caption, net of tax 1,819 Adjustments for fair value of the identifiable intangible assets: Identifiable indefinite lived intangible assets (insurance licenses) 6,800 Identifiable finite lived intangible assets (top broker relationships and renewal rights) 11,200 Identifiable intangible assets before tax impact 18,000 Other assets - deferred tax liability on identifiable intangible assets (2,281 ) Total adjustments for fair value of the identifiable intangible assets and value of business acquired, net of tax 15,719 Total adjustments for fair value by applicable balance sheet caption, identifiable intangible assets and value of business acquired, net of tax 17,538 Shareholders’ equity of TMR at fair value 1,050,499 Total net purchase price paid by RenaissanceRe 1,063,593 Excess purchase price over the fair value of net assets acquired assigned to goodwill $ 13,094 An explanation of the significant fair value adjustments and related future amortization is as follows: • Net deferred acquisition costs and value of business acquired (“VOBA”) - to reflect the elimination of TMR’s net deferred acquisition costs, partially offset by the establishment of the value of business acquired asset, which represents the present value of the expected underwriting profit within the unearned premiums liability, net of reinsurance, less costs to service the related policies and a risk premium. The adjustment for VOBA will be amortized to acquisition expenses over approximately two years , as the contracts for business in-force as of the acquisition date expire. VOBA at March 22, 2019 was $287.6 million ; • Reserve for claims and claim expenses - to reflect a decrease related to the present value of the net unpaid claims and claim expenses based on the estimated payout pattern, partially offset by an increase in net claims and claim expenses related to the estimated market based risk margin. The risk margin represents the estimated cost of capital required by a market participant to assume the net claims and claim expenses. This will be amortized using the projected discount and risk margin patterns of the net claims and claims expenses as of the acquisition date; • Identifiable indefinite lived and finite lived intangible assets - to establish the fair value of identifiable intangible assets related to the acquisition of TMR described in detail below; and • Other assets - to reflect the net deferred tax liability on identifiable intangible assets. Identifiable intangible assets and accumulated amortization at December 31, 2019 , consisted of the following, based on foreign exchange rates on March 22, 2019, and are included in goodwill and other intangible assets on the Company’s consolidated balance sheet: Amount Economic Useful Life Top broker relationships $ 10,000 10.0 years Renewal rights 1,200 15.0 years Insurance licenses 6,800 Indefinite Gross identifiable intangible assets related to the acquisition of TMR, at March 22, 2019 18,000 Accumulated amortization (from March 22, 2019 through December 31, 2019) 810 Net identifiable intangible assets related to the acquisition of TMR at December 31, 2019 $ 17,190 Amortization from the acquisition date, March 22, 2019, through December 31, 2019 was included in the Company's consolidated statements of operations for the year ended December 31, 2019 . An explanation of the identifiable intangible assets is as follows: • Top broker relationships - the value of TMR’s relationships with their top four brokers (Marsh & McLennan Companies, Inc., Aon plc, Willis Group Holdings Public Limited Company and Jardine Lloyd Thompson Group plc.) after taking into consideration the expectation of the renewal of these relationships and the associated expenses. These will be amortized on a straight-line basis over the economic useful life as of the acquisition date; • Renewal rights - the value of policy renewal rights after taking into consideration written premiums on assumed retention ratios and the insurance cash flows and the associated equity cash flows from these renewal policies over the expected life of the renewals. These will be amortized on a straight-line basis over the economic useful life as of the acquisition date; and • Insurance licenses - the value of acquired insurance licenses, which provide the ability to write reinsurance in all 50 states of the U.S. and the District of Columbia. As part of the allocation of the purchase price, included in the adjustment to other assets in the table above is a deferred tax liability of $2.3 million related to the estimated fair value of the intangible assets recorded, as well as a net deferred tax liability of $2.6 million related to certain other adjustments to the fair values of the assets acquired, VOBA, liabilities assumed and shareholders’ equity. Other net deferred tax liabilities recorded primarily relate to differences between financial reporting and tax bases of the acquired assets and liabilities as of the acquisition date, March 22, 2019. The Company estimates that none of the goodwill that was recorded will be deductible for income tax purposes. Financial Results The following table summarizes the net contribution from the acquisition of TMR since March 22, 2019 that has been included in the Company's consolidated statements of operations and comprehensive income for the year ended December 31, 2019 . Operating activities of TMR from the acquisition date, March 22, 2019, through December 31, 2019 are included in the Company’s consolidated statements of operations for the year ended December 31, 2019 . The unaudited net contribution of the acquisition and integration of TMR is provided for informational purposes only and is not necessarily, and should not be assumed to be, an indication of the results that may be achieved in the future. These results are not used as a part of management analysis of the financial performance of the Company’s business. These results primarily reflect items recorded directly by TMR, including: 1) net earned premium and net underwriting income on the in-force portfolio acquired with the acquisition of TMR and currently retained on TMR entities’ balance sheets; 2) net earned premium and net underwriting income for those contracts which have renewed post-acquisition on one of the acquired TMR entities’ balance sheets; 3) net investment income and net realized and unrealized gains recorded directly by TMR; and 4) certain direct costs incurred directly by TMR. In addition, these results, where possible, are adjusted for transaction and integration related costs incurred by the Company. However, these results do not reflect on-going operating costs incurred by the Company in supporting TMR unless such costs are incurred directly by TMR. These results also do not give consideration to the impact of possible revenue enhancements, expense efficiencies, synergies or asset dispositions that may be achieved in the future. These results involve significant estimates and are not indicative of the future results of the acquired TMR entities which will be further impacted by potential changes in targeted business mix, investment management strategies, and synergies recognized from changes in the combined entity’s operating structure, as well as the impact of changes in other business and capital management strategies. Since the acquisition date, a growing number of underlying policies have been underwritten onto different legal entities, staffing has been allocated to new activities, and reinsurance has been purchased to cover combined risks, only some of which would have been reflected in the underlying legacy TMR results. In future quarters, the summary results of TMR will become increasingly impracticable to produce, and even less indicative of the results of the acquired TMR entities, given the significant estimates involved and the nature and pace of our integration activities, which are intended to integrate TMR as quickly as possible. Year ended December 31, 2019 (1) Total revenues $ 922,727 Net income available to RenaissanceRe common shareholders (2) $ 99,169 (1) Includes the net contribution from the acquisition of TMR since March 22, 2019 that has been included in the Company’s consolidated statements of operations and comprehensive income through December 31, 2019 . (2) Includes $49.7 million of corporate expenses associated with the acquisition and integration of TMR for the year ended December 31, 2019 . Taxation At the date of acquisition and in conjunction with the acquisition of TMR, the Company established a net deferred tax liability of $5.7 million and recorded a valuation allowance against TMR’s deferred tax assets of $35.7 million in its consolidated financial statements. A predominant amount of the valuation allowance related to the U.S. operations of TMR was recorded by TMR prior to the acquisition. Supplemental Pro Forma Information The following table presents unaudited pro forma consolidated financial information for the years ended December 31, 2019 and 2018 , respectively, and assumes the acquisition of TMR occurred on January 1, 2018. The unaudited pro forma consolidated financial information is provided for informational purposes only and is not necessarily, and should not be assumed to be, an indication of the results that would have been achieved had the transaction been completed as of January 1, 2018 or that may be achieved in the future. The unaudited pro forma consolidated financial information does not give consideration to the impact of possible revenue enhancements, expense efficiencies, synergies or asset dispositions that may result from the acquisition of TMR. In addition, unaudited pro forma consolidated financial information does not include the effects of costs associated with any restructuring or integration activities resulting from the acquisition of TMR, as they are nonrecurring. Year ended December 31, 2019 2018 Total revenues $ 4,542,979 $ 3,338,903 Net income available to RenaissanceRe common shareholders $ 768,719 $ 281,974 Among other adjustments, and in addition to the fair value adjustments and recognition of goodwill, VOBA and identifiable intangible assets noted above, other material nonrecurring pro forma adjustments directly attributable to the acquisition of TMR principally included certain adjustments to recognize transaction related costs, align accounting policies, and amortize fair value adjustments, VOBA, and identifiable definite lived intangible assets, net of related tax impacts. Defined Benefit Pension Plan TMR has a contributory defined benefit pension plan for certain employees, which was not material to RenaissanceRe’s results of operations, financial condition or cash flows for the year ended December 31, 2019 . The plan offers mandatory benefits as prescribed by the applicable law, as well as voluntary benefits. These mandatory benefits include guarantees regarding the level of interest paid annually on accrued pension savings. TMR and the members of the plan contribute a defined percentage of salary to the pension arrangement and the rates on these accrued savings are converted into a pension payment at the time of retirement, and credit accumulation is earned on these contributions. At retirement, the accumulated contributions and interest credits are converted into a pension. At December 31, 2019 , the net balance sheet liability was $6.5 million , comprising $20.4 million of projected benefit obligation and $13.9 million of plan assets at fair value.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS The following table shows an analysis of goodwill and other intangible assets included in goodwill and other intangible assets on the Company’s consolidated balance sheets: Goodwill and other intangible assets Goodwill Other intangible assets Total Balance as of December 31, 2017 Gross amount $ 199,889 $ 96,599 $ 296,488 Accumulated impairment losses and amortization (2,299 ) (51,044 ) (53,343 ) 197,590 45,555 243,145 Amortization — (5,727 ) (5,727 ) Balance as of December 31, 2018 Gross amount 199,889 96,599 296,488 Accumulated impairment losses and amortization (2,299 ) (56,771 ) (59,070 ) 197,590 39,828 237,418 Acquired during the year 13,094 18,000 31,094 Amortization — (6,286 ) (6,286 ) Balance as of December 31, 2019 Gross amount 212,983 114,599 327,582 Accumulated impairment losses and amortization (2,299 ) (63,057 ) (65,356 ) $ 210,684 $ 51,542 $ 262,226 During the quarter ended March 31, 2019, the Company recognized goodwill of $13.1 million , based on foreign exchange rates on March 22, 2019, attributable to the excess of the purchase price over the fair value of the net assets acquired in the TMR Stock Purchase. In addition, the Company recognized identifiable finite lived intangible assets of $11.2 million and identifiable indefinite lived intangible assets of $6.8 million associated with TMR. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to goodwill and other intangible assets associated with the acquisition of TMR. The following table shows an analysis of goodwill and other intangible assets included in investments in other ventures, under equity method on the Company’s consolidated balance sheets: Goodwill and other intangible assets included in investments in other ventures, under equity method Goodwill Other intangible assets Total Balance as of December 31, 2017 Gross amount $ 12,318 $ 51,796 $ 64,114 Accumulated impairment losses and amortization (4,500 ) (42,880 ) (47,380 ) 7,818 8,916 16,734 Acquired during the year 2,780 11,108 13,888 Amortization — (2,886 ) (2,886 ) Balance as of December 31, 2018 Gross amount 15,098 62,904 78,002 Accumulated impairment losses and amortization (4,500 ) (45,766 ) (50,266 ) 10,598 17,138 27,736 Acquired during the year — 4 4 Amortization — (2,816 ) (2,816 ) Balance as of December 31, 2019 Gross amount 15,098 62,908 78,006 Accumulated impairment losses and amortization (4,500 ) (48,582 ) (53,082 ) $ 10,598 $ 14,326 $ 24,924 On March 23, 2018, the Company made an equity investment in TWFG Holding Company LLC (“TWFG”) and the transaction was accounted under the equity method of accounting . Total consideration paid was allocated to the Company’s proportionate share of the net assets of TWFG, other identifiable intangible assets and goodwill. In connection with the acquisition of TWFG, the Company recognized identifiable finite lived intangible assets of $2.0 million and identifiable indefinite lived intangible assets of $9.1 million . In addition, the Company recognized goodwill of $2.8 million . In accordance with the Company’s established accounting policy, the beginning of the fourth quarter was used as the date for performing the annual impairment test. The Company first assessed qualitative factors to determine whether it was necessary to perform a quantitative impairment test. Based on its qualitative assessment, the Company determined it was not more likely than not that the fair value of the goodwill and other intangible assets in question were less than their respective carrying amounts. The qualitative assessment included the following factors which the Company determined had not significantly deteriorated given specific facts and circumstances: macroeconomic conditions; industry and market conditions; costs factors; and overall financial performance. The Company also performed a quantitative analysis using a discounted cash flow model and concluded that the full amount of the goodwill and other intangible assets were not impaired. Other than the goodwill and other intangible assets acquired during the year as noted above and normal course amortization of intangible assets, in accordance with the Company’s established accounting policy, there were no adjustments to carried goodwill and other intangible assets during the year ended December 31, 2019 . The gross carrying value and accumulated amortization by major category of other intangible assets included in goodwill and other intangible assets and investments in other ventures, under equity method on the Company’s consolidated balance sheets is shown below: Other intangible assets At December 31, 2019 Gross carrying value Accumulated amortization and impairment losses Total Customer relationships and customer lists $ 108,651 $ (69,298 ) $ 39,353 Value of business acquired 20,200 (20,200 ) — Software 12,230 (12,230 ) — Licenses 26,186 — 26,186 Patents and intellectual property 4,500 (4,500 ) — Covenants not-to-compete 4,030 (4,030 ) — Trademarks and trade names 1,710 (1,381 ) 329 $ 177,507 $ (111,639 ) $ 65,868 Other intangible assets At December 31, 2018 Gross carrying value Accumulated amortization and impairment losses Total Customer relationships and customer lists $ 97,419 $ (60,221 ) $ 37,198 Value of business acquired 20,200 (20,200 ) — Software 12,230 (12,230 ) — Licenses 19,414 — 19,414 Patents and intellectual property 4,500 (4,500 ) — Covenants not-to-compete 4,030 (4,030 ) — Trademarks and trade names 1,710 (1,356 ) 354 $ 159,503 $ (102,537 ) $ 56,966 The remaining useful life of intangible assets with finite lives ranges from 0.5 to 14.2 years, with a weighted-average amortization period of 7.0 years. Expected amortization of the other intangible assets, including other intangible assets recorded in investments in other ventures, under equity method, is shown below: Other intangibles Other intangible assets included in investments in other ventures, under equity method Total 2020 $ 6,317 $ 1,955 $ 8,272 2021 5,990 1,095 7,085 2022 5,602 1,095 6,697 2023 5,173 631 5,804 2024 4,716 194 4,910 2024 and thereafter 6,705 209 6,914 Total remaining amortization expense 34,503 5,179 39,682 Indefinite lived 17,039 9,147 26,186 Total $ 51,542 $ 14,326 $ 65,868

Investments

Investments	12 Months Ended
	Dec. 31, 2019
Investments [Abstract]
Investments	INVESTMENTS Fixed Maturity Investments Trading The following table summarizes the fair value of fixed maturity investments trading: December 31, December 31, U.S. treasuries $ 4,467,345 $ 3,331,411 Agencies 343,031 174,883 Municipal — 6,854 Non-U.S. government 497,392 279,818 Non-U.S. government-backed corporate 321,356 160,063 Corporate 3,075,660 2,450,244 Agency mortgage-backed 1,148,499 817,880 Non-agency mortgage-backed 294,604 278,680 Commercial mortgage-backed 468,698 282,294 Asset-backed 555,070 306,743 Total fixed maturity investments trading $ 11,171,655 $ 8,088,870 Contractual maturities of fixed maturity investments trading are described in the following table. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. At December 31, 2019 Amortized Cost Fair Value Due in less than one year $ 543,687 $ 544,636 Due after one through five years 5,467,501 5,522,769 Due after five through ten years 2,386,467 2,420,602 Due after ten years 211,424 216,777 Mortgage-backed 1,902,365 1,911,801 Asset-backed 555,970 555,070 Total $ 11,067,414 $ 11,171,655 Equity Investments Trading The following table summarizes the fair value of equity investments trading: December 31, December 31, Financials $ 248,189 $ 200,357 Communications and technology 79,206 42,333 Industrial, utilities and energy 38,583 24,520 Consumer 35,987 20,639 Healthcare 29,510 18,925 Basic materials 5,456 3,478 Total $ 436,931 $ 310,252 Pledged Investments At December 31, 2019 , $7.0 billion of cash and investments at fair value were on deposit with, or in trust accounts for the benefit of, various counterparties, including with respect to the Company’s letter of credit facilities ( 2018 - $5.7 billion ). Of this amount, $2.0 billion is on deposit with, or in trust accounts for the benefit of, U.S. state regulatory authorities ( 2018 - $2.0 billion ). Reverse Repurchase Agreements At December 31, 2019 , the Company held $57.6 million ( 2018 - $3.7 million ) of reverse repurchase agreements. These loans are fully collateralized, are generally outstanding for a short period of time and are presented on a gross basis as part of short term investments on the Company’s consolidated balance sheets. The required collateral for these loans typically includes high-quality, readily marketable instruments at a minimum amount of 102% of the loan principal. Upon maturity, the Company receives principal and interest income. Net Investment Income The components of net investment income are as follows: Year ended December 31, 2019 2018 2017 Fixed maturity investments $ 318,503 $ 211,973 $ 179,624 Short term investments 56,264 33,571 11,082 Equity investments 4,808 4,474 3,628 Other investments Private equity investments 14,981 477 33,999 Other 39,246 22,475 8,067 Cash and cash equivalents 7,676 3,810 1,196 441,478 276,780 237,596 Investment expenses (17,645 ) (14,914 ) (15,387 ) Net investment income $ 423,833 $ 261,866 $ 222,209 Net Realized and Unrealized Gains (Losses) on Investments Net realized and unrealized gains (losses) on investments are as follows: Year ended December 31, 2019 2018 2017 Gross realized gains $ 133,409 $ 21,284 $ 49,121 Gross realized losses (43,149 ) (91,098 ) (38,832 ) Net realized gains (losses) on fixed maturity investments 90,260 (69,814 ) 10,289 Net unrealized gains (losses) on fixed maturity investments trading 170,183 (57,310 ) 8,479 Net realized and unrealized gains (losses) on investments-related derivatives 58,891 (8,784 ) (2,490 ) Net realized gains on equity investments trading sold during the period 31,062 27,739 80,027 Net unrealized gains (losses) on equity investments trading still held at reporting date 64,087 (66,900 ) 39,517 Net realized and unrealized gains (losses) on equity investments trading 95,149 (39,161 ) 119,544 Net realized and unrealized gains (losses) on investments $ 414,483 $ (175,069 ) $ 135,822 Other Investments The table below shows the fair value of the Company’s portfolio of other investments: At December 31, 2019 2018 Catastrophe bonds $ 781,641 $ 516,571 Private equity investments 271,047 242,647 Senior secured bank loan funds 22,598 14,482 Hedge funds 12,091 11,233 Total other investments $ 1,087,377 $ 784,933 Interest income, income distributions and net realized and unrealized gains on other investments are included in net investment income and totaled $54.2 million ( 2018 – $23.0 million , 2017 – $42.1 million ) of which $12.2 million related to net unrealized gains ( 2018 – losses of $8.3 million , 2017 – gains of $24.7 million ). Included in net investment income for 2019 is a loss of $5.5 million ( 2018 - income of $0.3 million , 2017 - income of $1.9 million ) representing the change in estimate during the period related to the difference between the Company’s estimated fair value due to the lag in reporting, as discussed in “Note 2 . Significant Accounting Policies,” and the actual amount as reported in the final net asset values provided by the Company’s fund managers. The Company has committed capital to private equity investments, other investments and investments in other ventures of $1.1 billion , of which $708.4 million has been contributed at December 31, 2019 . The Company’s remaining commitments to these investments at December 31, 2019 totaled $411.3 million . In the future, the Company may enter into additional commitments in respect of private equity investments or individual portfolio company investment opportunities. Investments in Other Ventures, under Equity Method The table below shows the Company’s portfolio of investments in other ventures, under equity method: 2019 2018 At December 31, Ownership % Carrying Value Ownership % Carrying Value Tower Hill Companies 24.9 % 36,779 24.9 % 38,241 Top Layer Re 50.0 % 35,363 50.0 % 46,562 Other 26.6 % 34,407 30.6 % 30,369 Total investments in other ventures, under equity method $ 106,549 $ 115,172 The table below shows the Company’s equity in earnings of other ventures, under equity method: Year ended December 31, 2019 2018 2017 Tower Hill Companies $ 10,337 $ 9,605 $ (1,647 ) Top Layer Re 8,801 8,852 9,851 Other 4,086 17 (174 ) Total equity in earnings of other ventures $ 23,224 $ 18,474 $ 8,030 During 2019 , the Company received $36.5 million of distributions from its investments in other ventures, under equity method ( 2018 – $26.1 million , 2017 – $29.7 million ). Losses from the Company’s investments in other ventures, under equity method, net of distributions received, were $0.8 million at December 31, 2019 ( 2018 - earnings of $3.8 million , 2017 - losses of $6.3 million ). Except for Top Layer Re, the equity in earnings of the Company’s investments in other ventures are reported one quarter in arrears.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS The use of fair value to measure certain assets and liabilities with resulting unrealized gains or losses is pervasive within the Company’s consolidated financial statements. Fair value is defined under accounting guidance currently applicable to the Company to be the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between open market participants at the measurement date. The Company recognizes the change in unrealized gains and losses arising from changes in fair value in its consolidated statements of operations. FASB ASC Topic Fair Value Measurements and Disclosures prescribes a fair value hierarchy that prioritizes the inputs to the respective valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to valuation techniques that use at least one significant input that is unobservable (Level 3). The three levels of the fair value hierarchy are described below: • Fair values determined by Level 1 inputs utilize unadjusted quoted prices obtained from active markets for identical assets or liabilities for which the Company has access. The fair value is determined by multiplying the quoted price by the quantity held by the Company; • Fair values determined by Level 2 inputs utilize inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets and liabilities in active markets, and inputs other than quoted prices that are observable for the asset or liability, such as interest rates and yield curves that are observable at commonly quoted intervals, broker quotes and certain pricing indices; and • Level 3 inputs are based all or in part on significant unobservable inputs for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. In these cases, significant management assumptions can be used to establish management’s best estimate of the assumptions used by other market participants in determining the fair value of the asset or liability. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, the level in the fair value hierarchy within which the fair value measurement in its entirety falls has been determined based on the lowest level input that is significant to the fair value measurement of the asset or liability. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and the Company considers factors specific to the asset or liability. In order to determine if a market is active or inactive for a security, the Company considers a number of factors, including, but not limited to, the spread between what a seller is asking for a security and what a buyer is bidding for the same security, the volume of trading activity for the security in question, the price of the security compared to its par value (for fixed maturity investments), and other factors that may be indicative of market activity. There have been no material changes in the Company’s valuation techniques, nor have there been any transfers between Level 1 and Level 2, or Level 2 and Level 3 during the period represented by these consolidated financial statements. Below is a summary of the assets and liabilities that are measured at fair value on a recurring basis and also represents the carrying amount on the Company’s consolidated balance sheets: At December 31, 2019 Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fixed maturity investments U.S. treasuries $ 4,467,345 $ 4,467,345 $ — $ — Agencies 343,031 — 343,031 — Non-U.S. government 497,392 — 497,392 — Non-U.S. government-backed corporate 321,356 — 321,356 — Corporate 3,075,660 — 3,075,660 — Agency mortgage-backed 1,148,499 — 1,148,499 — Non-agency mortgage-backed 294,604 — 294,604 — Commercial mortgage-backed 468,698 — 468,698 — Asset-backed 555,070 — 555,070 — Total fixed maturity investments 11,171,655 4,467,345 6,704,310 — Short term investments 4,566,277 — 4,566,277 — Equity investments trading 436,931 436,931 — — Other investments Catastrophe bonds 781,641 — 781,641 — Private equity investments (1) 271,047 — — 74,634 Senior secured bank loan funds (1) 22,598 — — — Hedge funds (1) 12,091 — — — Total other investments 1,087,377 — 781,641 74,634 Other assets and (liabilities) Assumed and ceded (re)insurance contracts (2) 4,731 — — 4,731 Derivatives (3) 16,937 (1,020 ) 17,957 — Total other assets and (liabilities) 21,668 (1,020 ) 17,957 4,731 $ 17,283,908 $ 4,903,256 $ 12,070,185 $ 79,365 (1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated balance sheet. (2) Included in assumed and ceded (re)insurance contracts at December 31, 2019 was $32.9 million of other assets and $28.2 million of other liabilities. (3) Refer to “Note 19 . Derivative Instruments” for additional information related to the fair value, by type of contract, of derivatives entered into by the Company. At December 31, 2018 Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fixed maturity investments U.S. treasuries $ 3,331,411 $ 3,331,411 $ — $ — Agencies 174,883 — 174,883 — Municipal 6,854 — 6,854 — Non-U.S. government 279,818 — 279,818 — Non-U.S. government-backed corporate 160,063 — 160,063 — Corporate 2,450,244 — 2,450,244 — Agency mortgage-backed 817,880 — 817,880 — Non-agency mortgage-backed 278,680 — 278,680 — Commercial mortgage-backed 282,294 — 282,294 — Asset-backed 306,743 — 306,743 — Total fixed maturity investments 8,088,870 3,331,411 4,757,459 — Short term investments 2,586,520 — 2,586,520 — Equity investments trading 310,252 310,252 — — Other investments Catastrophe bonds 516,571 — 516,571 — Private equity investments (1) 242,647 — — 54,545 Senior secured bank loan funds (1) 14,482 — — — Hedge funds (1) 11,233 — — — Total other investments 784,933 — 516,571 54,545 Other assets and (liabilities) Assumed and ceded (re)insurance contracts (2) (8,359 ) — — (8,359 ) Derivatives (3) 12,399 484 11,915 — Total other assets and (liabilities) 4,040 484 11,915 (8,359 ) $ 11,774,615 $ 3,642,147 $ 7,872,465 $ 46,186 (1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated balance sheet. (2) Included in assumed and ceded (re)insurance contracts at December 31, 2018 was $5.0 million of other assets and $13.3 million of other liabilities. (3) Refer to “Note 19 . Derivative Instruments” for additional information related to the fair value, by type of contract, of derivatives entered into by the Company. Level 1 and Level 2 Assets and Liabilities Measured at Fair Value Fixed Maturity Investments Fixed maturity investments included in Level 1 consist of the Company’s investments in U.S. treasuries. Fixed maturity investments included in Level 2 are agencies, municipal, non-U.S. government, non-U.S. government-backed corporate, corporate, agency mortgage-backed, non-agency mortgage-backed, commercial mortgage-backed and asset-backed. The Company’s fixed maturity investments are primarily priced using pricing services, such as index providers and pricing vendors, as well as broker quotations. In general, the pricing vendors provide pricing for a high volume of liquid securities that are actively traded. For securities that do not trade on an exchange, the pricing services generally utilize market data and other observable inputs in matrix pricing models to determine month end prices. Observable inputs include benchmark yields, reported trades, broker-dealer quotes, issuer spreads, bids, offers, reference data and industry and economic events. Index pricing generally relies on market traders as the primary source for pricing; however, models are also utilized to provide prices for all index eligible securities. The models use a variety of observable inputs such as benchmark yields, transactional data, dealer runs, broker-dealer quotes and corporate actions. Prices are generally verified using third-party data. Securities which are priced by an index provider are generally included in the index. In general, broker-dealers value securities through their trading desks based on observable inputs. The methodologies include mapping securities based on trade data, bids or offers, observed spreads, and performance on newly issued securities. Broker-dealers also determine valuations by observing secondary trading of similar securities. Prices obtained from broker quotations are considered non-binding, however they are based on observable inputs and by observing secondary trading of similar securities obtained from active, non-distressed markets. The Company considers these broker quotations to be Level 2 inputs as they are corroborated with other market observable inputs. The techniques generally used to determine the fair value of the Company’s fixed maturity investments are detailed below by asset class. U.S. treasuries Level 1 - At December 31, 2019 , the Company’s U.S. treasuries fixed maturity investments were primarily priced by pricing services and had a weighted average yield to maturity of 1.7% and a weighted average credit quality of AA ( 2018 - 2.5% and AA, respectively). When pricing these securities, the pricing services utilize daily data from many real time market sources, including active broker-dealers. Certain data sources are regularly reviewed for accuracy to attempt to ensure the most reliable price source is used for each issue and maturity date. Agencies Level 2 - At December 31, 2019 , the Company’s agency fixed maturity investments had a weighted average yield to maturity of 2.1% and a weighted average credit quality of AA ( 2018 - 3.0% and AA, respectively). The issuers of the Company’s agency fixed maturity investments primarily consist of the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation and other agencies. Fixed maturity investments included in agencies are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources and integrate other observations from markets and sector news. Evaluations are updated by obtaining broker-dealer quotes and other market information including actual trade volumes, when available. The fair value of each security is individually computed using analytical models which incorporate option adjusted spreads and other daily interest rate data. Municipal Level 2 - At December 31, 2019 , the Company did no t hold any material positions in municipal fixed maturity investments. At December 31, 2018 , the Company’s municipal fixed maturity investments had a weighted average yield to maturity of 4.8% and a weighted average credit quality of A. The Company’s municipal fixed maturity investments were primarily priced by pricing services. When evaluating these securities, the pricing services gathered information regarding the security from third-party sources such as trustees, paying agents or issuers. Evaluations were updated by obtaining broker-dealer quotes and other market information including actual trade volumes, when available. The pricing services also considered the specific terms and conditions of the securities, including any specific features which may have influenced risk. In certain instances, securities were individually evaluated using a spread over widely accepted market benchmarks. Non-U.S. government Level 2 - At December 31, 2019 , the Company’s non-U.S. government fixed maturity investments had a weighted average yield to maturity of 1.6% and a weighted average credit quality of AA ( 2018 - 2.7% and AAA, respectively). The issuers of securities in this sector are non-U.S. governments and their respective agencies as well as supranational organizations. Securities held in these sectors are primarily priced by pricing services that employ proprietary discounted cash flow models to value the securities. Key quantitative inputs for these models are daily observed benchmark curves for treasury, swap and high issuance credits. The pricing services then apply a credit spread for each security which is developed by in-depth and real time market analysis. For securities in which trade volume is low, the pricing services utilize data from more frequently traded securities with similar attributes. These models may also be supplemented by daily market and credit research for international markets. Non-U.S. government-backed corporate Level 2 - At December 31, 2019 , the Company’s non-U.S. government-backed corporate fixed maturity investments had a weighted average yield to maturity of 2.0% and a weighted average credit quality of AA ( 2018 - 2.8% and AA, respectively). Non-U.S. government-backed corporate fixed maturity investments are primarily priced by pricing services that employ proprietary discounted cash flow models to value the securities. Key quantitative inputs for these models are daily observed benchmark curves for treasury, swap and high issuance credits. The pricing services then apply a credit spread to the respective curve for each security which is developed by in-depth and real time market analysis. For securities in which trade volume is low, the pricing services utilize data from more frequently traded securities with similar attributes. These models may also be supplemented by daily market and credit research for international markets. Corporate Level 2 - At December 31, 2019 , the Company’s corporate fixed maturity investments principally consisted of U.S. and international corporations and had a weighted average yield to maturity of 3.0% and a weighted average credit quality of BBB ( 2018 - 4.9% and BBB, respectively). The Company’s corporate fixed maturity investments are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources regarding the issuer of the security and obtain credit data, as well as other observations, from markets and sector news. Evaluations are updated by obtaining broker-dealer quotes and other market information including actual trade volumes, when available. The pricing services also consider the specific terms and conditions of the securities, including any specific features which may influence risk. In certain instances, securities are individually evaluated using a spread which is added to the U.S. treasury curve or a security specific swap curve as appropriate. Agency mortgage-backed Level 2 - At December 31, 2019 , the Company’s agency mortgage-backed fixed maturity investments included agency residential mortgage-backed securities with a weighted average yield to maturity of 2.5% , a weighted average credit quality of AA and a weighted average life of 4.9 years ( 2018 - 3.5% , AA and 7.1 years, respectively). The Company’s agency mortgage-backed fixed maturity investments are primarily priced by pricing services using a mortgage pool specific model which utilizes daily inputs from the active to-be-announced market which is very liquid, as well as the U.S. treasury market. The model also utilizes additional information, such as the weighted average maturity, weighted average coupon and other available pool level data which is provided by the sponsoring agency. Valuations are also corroborated with daily active market quotes. Non-agency mortgage-backed Level 2 - The Company’s non-agency mortgage-backed fixed maturity investments include non-agency prime, non-agency Alt-A and other non-agency residential mortgage-backed securities. At December 31, 2019 , the Company’s non-agency prime residential mortgage-backed fixed maturity investments had a weighted average yield to maturity of 3.3% , a weighted average credit quality of BBB, and a weighted average life of 4.8 years ( 2018 - 4.4% , non-investment grade and 4.7 years, respectively). The Company’s non-agency Alt-A fixed maturity investments held at December 31, 2019 had a weighted average yield to maturity of 3.8% , a weighted average credit quality of non-investment grade and a weighted average life of 6.3 years ( 2018 - 4.7% , non-investment grade and 6.3 years, respectively). Securities held in these sectors are primarily priced by pricing services using an option adjusted spread model or other relevant models, which principally utilize inputs including benchmark yields, available trade information or broker quotes, and issuer spreads. The pricing services also review collateral prepayment speeds, loss severity and delinquencies among other collateral performance indicators for the securities valuation, when applicable. Commercial mortgage-backed Level 2 - At December 31, 2019 , the Company’s commercial mortgage-backed fixed maturity investments had a weighted average yield to maturity of 2.6% , a weighted average credit quality of AAA, and a weighted average life of 5.7 years ( 2018 - 3.6% , AAA and 5.0 years, respectively). Securities held in these sectors are primarily priced by pricing services. The pricing services apply dealer quotes and other available trade information such as bids and offers, prepayment speeds which may be adjusted for the underlying collateral or current price data, the U.S. treasury curve and swap curve as well as cash settlement. The pricing services discount the expected cash flows for each security held in this sector using a spread adjusted benchmark yield based on the characteristics of the security. Asset-backed Level 2 - At December 31, 2019 , the Company’s asset-backed fixed maturity investments had a weighted average yield to maturity of 3.3% , a weighted average credit quality of AAA and a weighted average life of 3.2 years ( 2018 - 4.3% , AAA and 3.2 years, respectively). The underlying collateral for the Company’s asset-backed fixed maturity investments primarily consists of bank loans, student loans, credit card receivables, auto loans and other receivables. Securities held in these sectors are primarily priced by pricing services. The pricing services apply dealer quotes and other available trade information such as bids and offers, prepayment speeds which may be adjusted for the underlying collateral or current price data, the U.S. treasury curve and swap curve as well as cash settlement. The pricing services determine the expected cash flows for each security held in this sector using historical prepayment and default projections for the underlying collateral and current market data. In addition, a spread is applied to the relevant benchmark and used to discount the cash flows noted above to determine the fair value of the securities held in this sector. Short Term Investments Level 2 - At December 31, 2019 , the Company’s short term investments had a weighted average yield to maturity of 1.6% and a weighted average credit quality of AAA ( 2018 - 2.1% and AAA, respectively). The fair value of the Company’s portfolio of short term investments is generally determined using amortized cost which approximates fair value and, in certain cases, in a manner similar to the Company’s fixed maturity investments noted above. Equity Investments, Classified as Trading Level 1 - The fair value of the Company’s portfolio of equity investments, classified as trading is primarily priced by pricing services, reflecting the closing price quoted for the final trading day of the period. When pricing these securities, the pricing services utilize daily data from many real time market sources, including applicable securities exchanges. All data sources are regularly reviewed for accuracy to attempt to ensure the most reliable price source was used for each security. Other investments Catastrophe bonds Level 2 - The Company’s other investments include investments in catastrophe bonds which are recorded at fair value based on broker or underwriter bid indications. Other assets and liabilities Derivatives Level 1 and Level 2 - Other assets and liabilities include certain derivatives entered into by the Company. The fair value of these transactions includes certain exchange traded futures contracts which are considered Level 1, and foreign currency contracts and certain credit derivatives, determined using standard industry valuation models and considered Level 2, as the inputs to the valuation model are based on observable market inputs. For credit derivatives, these inputs include credit spreads, credit ratings of the underlying referenced security, the risk free rate and the contract term. For foreign currency contracts, these inputs include spot rates and interest rate curves. Level 3 Assets and Liabilities Measured at Fair Value Below is a summary of quantitative information regarding the significant unobservable inputs (Level 3) used in determining the fair value of assets and liabilities measured at fair value on a recurring basis: At December 31, 2019 Fair Value Valuation Technique Unobservable Inputs Low High Weighted Average or Actual Other investments Private equity investment $ 10,327 External valuation model Manager pricing $ 103.20 $ 103.77 $ 103.20 Private equity investments 64,307 Internal valuation model Discount rate 8.0 % 10.0 % 9.0 % Liquidity discount n/a n/a 15.0 % Total other investments 74,634 Other assets and (liabilities) Assumed and ceded (re)insurance contracts 501 Internal valuation model Bond price $ 100.29 $ 106.26 $ 103.58 Liquidity discount n/a n/a 1.3 % Assumed and ceded (re)insurance contracts (8,767 ) Internal valuation model Net undiscounted cash flows n/a n/a $ (11,179 ) Expected loss ratio n/a n/a 33.1 % Discount rate n/a n/a 1.7 % Assumed and ceded (re)insurance contracts 12,997 Internal valuation model Expected loss ratio n/a n/a 0.0 % Total other assets and (liabilities) 4,731 Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs $ 79,365 Below is a reconciliation of the beginning and ending balances, for the periods shown, of assets and liabilities measured at fair value on a recurring basis using Level 3 inputs. Interest and dividend income are included in net investment income and are excluded from the reconciliation. Other investments Other assets and (liabilities) Total Balance - January 1, 2019 $ 54,545 $ (8,359 ) $ 46,186 Total realized and unrealized gains (losses) Included in other income 2,126 (2,347 ) (221 ) Total foreign exchange gains 5 — 5 Purchases 17,958 (4,553 ) 13,405 Settlements — 20 20 Amounts acquired (1) — 19,970 19,970 Balance - December 31, 2019 $ 74,634 $ 4,731 $ 79,365 (1) Represents the fair value of the other assets acquired from TMR, measured at fair value on a recurring basis using Level 3 inputs at March 22, 2019. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. Other Other assets and (liabilities) Total Balance - January 1, 2018 $ — $ (2,952 ) $ (2,952 ) Total realized and unrealized gains Included in other income — 2,901 2,901 Purchases 54,545 (9,291 ) 45,254 Settlements — 983 983 Balance - December 31, 2018 $ 54,545 $ (8,359 ) $ 46,186 Other investments Private equity investment Level 3 - At December 31, 2019 , the Company’s other investments included a $10.3 million private equity investment which is recorded at fair value, with the fair value obtained through the receipt of an indicative pricing obtained from the insurance manager of the security. The Company considers the price obtained to be unobservable, as there is little, if any, market activity for this security. This unobservable input in isolation can cause significant increases or decreases in fair value. Generally, an increase in the indicative pricing would result in an increase in the fair value of this private equity investment. Level 3 - At December 31, 2019 , the Company’s other investments included $64.3 million of private equity investments which are recorded at fair value, with the fair value obtained through the use of internal valuation models. The Company measured the fair value of these investments using multiples of net tangible book value of the underlying entity. The significant unobservable inputs used in the fair value measurement of these investments are liquidity discount rates applied to each of the net tangible book value multiples used in the internal valuation models, and discount rates applied to the expected cash flows of the underlying entity in various scenarios. These unobservable inputs in isolation can cause significant increases or decreases in fair value. Generally, an increase in the liquidity discount rate or discount rates would result in a decrease in the fair value of these private equity investments. Other assets and liabilities Assumed and ceded (re)insurance contracts Level 3 - At December 31, 2019 , the Company had a $0.5 million net asset related to an assumed reinsurance contract accounted for at fair value, with the fair value obtained through the use of an internal valuation model. The inputs to the internal valuation model are principally based on indicative pricing obtained from independent brokers and pricing vendors for similarly structured marketable securities. The most significant unobservable inputs include prices for similar marketable securities and a liquidity premium. The Company considers the prices for similar securities to be unobservable, as there is little, if any market activity for these similar assets. In addition, the Company has estimated a liquidity premium that would be required if the Company attempted to effectively exit its position by executing a short sale of these securities. Generally, an increase in the prices for similar marketable securities or a decrease in the liquidity premium would result in an increase in the expected profit and ultimate fair value of this assumed reinsurance contract. Level 3 - At December 31, 2019 , the Company had a $8.8 million net liability related to assumed and ceded (re)insurance contracts accounted for at fair value, with the fair value obtained through the use of an internal valuation model. The inputs to the internal valuation model are principally based on proprietary data as observable market inputs are generally not available. The most significant unobservable inputs include the assumed and ceded expected net cash flows related to the contracts, including the expected premium, acquisition expenses and losses; the expected loss ratio and the relevant discount rate used to present value the net cash flows. The contract period and acquisition expense ratio are considered an observable input as each is defined in the contract. Generally, an increase in the net expected cash flows and expected term of the contract and a decrease in the discount rate, expected loss ratio or acquisition expense ratio, would result in an increase in the expected profit and ultimate fair value of these assumed and ceded (re)insurance contracts. Level 3 - At December 31, 2019 , the Company had a $13.0 million net asset related to assumed and ceded (re)insurance contracts accounted for at fair value, with the fair value obtained through the use of internal valuation models. The inputs to the models are primarily based on the unexpired period of risk and an evaluation of the probability of loss. The fair value of the contracts are sensitive to loss-triggering events. In the event of a loss, the Company would adjust the fair value of the contract to account for a recovery or liability in accordance with the contract terms and the estimate of exposure under the contract. The inputs for the contracts are based on management’s evaluation and are unobservable. Financial Instruments Disclosed, But Not Carried, at Fair Value The Company uses various financial instruments in the normal course of its business. The Company’s insurance contracts are excluded from the fair value of financial instruments accounting guidance, unless the Company elects the fair value option, and therefore, are not included in the amounts discussed herein. The carrying values of cash and cash equivalents, accrued investment income, receivables for investments sold, certain other assets, payables for investments purchased, certain other liabilities, and other financial instruments not included herein approximated their fair values. Debt Included on the Company’s consolidated balance sheet at December 31, 2019 were debt obligations of $1.4 billion ( 2018 - $991.1 million ). At December 31, 2019 , the fair value of the Company’s debt obligations was $1.5 billion ( 2018 – $974.7 million ). The fair value of the Company’s debt obligations is determined using indicative market pricing obtained from third-party service providers, which the Company considers Level 2 in the fair value hierarchy. There have been no changes during the period in the Company’s valuation technique used to determine the fair value of the Company’s debt obligations. Refer to “Note 9 . Debt and Credit Facilities” for additional information related to the Company’s debt obligations. The Fair Value Option for Financial Assets and Financial Liabilities The Company has elected to account for certain financial assets and financial liabilities at fair value using the guidance under FASB ASC Topic Financial Instruments as the Company believes it represents the most meaningful measurement basis for these assets and liabilities. Below is a summary of the balances the Company has elected to account for at fair value: 2019 2018 Other investments $ 1,087,377 $ 784,933 Other assets $ 32,944 $ 4,968 Other liabilities $ 28,213 $ 13,327 Included in net investment income for 2019 was net unrealized gains of $12.2 million related to the changes in fair value of other investments ( 2018 – losses of $8.3 million , 2017 – gains of $24.7 million ). Included in other income for 2019 were net unrealized gains of $Nil related to the changes in the fair value of other assets and liabilities ( 2018 – $Nil , 2017 – $Nil ). Measuring the Fair Value of Other Investments Using Net Asset Valuations The table below shows the Company’s portfolio of other investments measured using net asset valuations as a practical expedient: At December 31, 2019 Fair Value Unfunded Redemption Frequency Redemption Redemption Private equity investments $ 196,413 $ 351,028 See below See below See below Senior secured bank loan funds 22,598 8,702 See below See below See below Hedge funds 12,091 — See below See below See below Total other investments measured using net asset valuations $ 231,102 $ 359,730 Private equity investments – A significant portion of the Company’s investments in private equity investments include alternative asset limited partnerships (or similar corporate structures) that invest in certain private equity asset classes including U.S. and global leveraged buyouts, mezzanine investments, distressed securities, real estate, and oil, gas and power. The Company generally has no right to redeem its interest in any of these private equity investments in advance of dissolution of the applicable private equity investment. Instead, the nature of these investments is that distributions are received by the Company in connection with the liquidation of the underlying assets of the respective private equity investment. It is estimated that the majority of the underlying assets of the limited partnerships would liquidate over 7 to 10 years from inception of the respective limited partnership. Senior secured bank loan funds – At December 31, 2019 the Company had $22.6 million invested in closed end funds which invest primarily in loans. The Company has no right to redeem its investment in these funds. It is estimated that the majority of the underlying assets in these closed end funds would begin to liquidate over 4 to 5 years from inception

Reinsurance

Reinsurance	12 Months Ended
	Dec. 31, 2019
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]
Reinsurance	REINSURANCE The Company purchases reinsurance and other protection to manage its risk portfolio and to reduce its exposure to large losses. The Company currently has in place contracts that provide for recovery of a portion of certain claims and claim expenses, generally in excess of various retentions or on a proportional basis. In addition to loss recoveries, certain of the Company’s ceded reinsurance contracts provide for payments of additional premiums, for reinstatement premiums and for lost no-claims bonuses, which are incurred when losses are ceded to the respective reinsurance contracts. The Company remains liable to the extent that any reinsurer fails to meet its obligations. The following table sets forth the effect of reinsurance and retrocessional activity on premiums written and earned and on net claims and claim expenses incurred: Year ended December 31, 2019 2018 2017 Premiums written Direct $ 461,409 $ 337,587 $ 290,730 Assumed 4,346,341 2,972,840 2,506,810 Ceded (1,426,257 ) (1,178,525 ) (926,215 ) Net premiums written $ 3,381,493 $ 2,131,902 $ 1,871,325 Premiums earned Direct $ 404,525 $ 292,219 $ 244,285 Assumed 4,348,261 2,779,796 2,307,219 Ceded (1,414,383 ) (1,095,886 ) (833,929 ) Net premiums earned $ 3,338,403 $ 1,976,129 $ 1,717,575 Claims and claim expenses Gross claims and claim expenses incurred $ 3,221,778 $ 2,578,536 $ 3,420,388 Claims and claim expenses recovered (1,124,757 ) (1,458,518 ) (1,558,960 ) Net claims and claim expenses incurred $ 2,097,021 $ 1,120,018 $ 1,861,428 At December 31, 2019 , the Company’s reinsurance recoverable balance was $2.8 billion ( 2018 - $2.4 billion ). Of the Company’s reinsurance recoverable balance at December 31, 2019 , 57.5% is fully collateralized by our reinsurers, 41.0% is recoverable from reinsurers rated A- or higher by major rating agencies and 1.5% is recoverable from reinsurers rated lower than A- by major rating agencies ( 2018 - 60.8% , 38.0% and 1.2% , respectively). The reinsurers with the three largest balances accounted for 12.7% , 7.2% and 7.0% , respectively, of the Company’s reinsurance recoverable balance at December 31, 2019 ( 2018 - 15.5% , 6.7% and 6.5% , respectively). The valuation allowance recorded against reinsurance recoverable was $7.3 million at December 31, 2019 ( 2018 - $9.0 million ). The three largest company-specific components of the valuation allowance represented 18.1% , 7.9% and 7.2% , respectively, of the Company’s total valuation allowance at December 31, 2019 ( 2018 - 16.2% , 14.8% and 12.3% , respectively).

Reserve for Claims and Claim Ex

Reserve for Claims and Claim Expenses	12 Months Ended
	Dec. 31, 2019
Insurance [Abstract]
Reserve for Claims and Claim Expenses	RESERVE FOR CLAIMS AND CLAIM EXPENSES The Company believes the most significant accounting judgment made by management is its estimate of claims and claim expense reserves. Claims and claim expense reserves represent estimates, including actuarial and statistical projections at a given point in time, of the ultimate settlement and administration costs for unpaid claims and claim expenses arising from the insurance and reinsurance contracts the Company sells. The Company establishes its claims and claim expense reserves by taking claims reported to the Company by insureds and ceding companies, but which have not yet been paid (“case reserves”), adding estimates for the anticipated cost of claims incurred but not yet reported to the Company, or incurred but not enough reported to the Company (collectively referred to as “IBNR”) and, if deemed necessary, adding costs for additional case reserves which represent the Company’s estimates for claims related to specific contracts previously reported to the Company which it believes may not be adequately estimated by the client as of that date, or adequately covered in the application of IBNR. The Company’s reserving committee, which includes members of the Company’s senior management, reviews, discusses, and assesses the reasonableness and adequacy of the reserving estimates included in our audited financial statements. The following table summarizes the Company’s claims and claim expense reserves by segment, allocated between case reserves, additional case reserves and IBNR: At December 31, 2019 Case Reserves Additional Case Reserves IBNR Total Property $ 1,253,406 $ 1,631,223 $ 1,189,221 $ 4,073,850 Casualty and Specialty 1,596,426 129,720 3,583,913 5,310,059 Other 440 — — 440 Total $ 2,850,272 $ 1,760,943 $ 4,773,134 $ 9,384,349 At December 31, 2018 Property $ 690,718 $ 1,308,307 $ 1,087,229 $ 3,086,254 Casualty and Specialty 771,537 116,877 2,096,979 2,985,393 Other 1,458 — 3,166 4,624 Total $ 1,463,713 $ 1,425,184 $ 3,187,374 $ 6,076,271 Activity in the liability for unpaid claims and claim expenses is summarized as follows: Year ended December 31, 2019 2018 2017 Net reserves as of beginning of period $ 3,704,050 $ 3,493,778 $ 2,568,730 Net incurred related to: Current year 2,123,876 1,390,767 1,902,424 Prior years (26,855 ) (270,749 ) (40,996 ) Total net incurred 2,097,021 1,120,018 1,861,428 Net paid related to: Current year 265,649 391,061 450,527 Prior years 832,405 503,708 524,298 Total net paid 1,098,054 894,769 974,825 Amounts acquired (1) 1,858,775 — — Foreign exchange (2) 31,260 (14,977 ) 38,445 Net reserves as of end of period 6,593,052 3,704,050 3,493,778 Reinsurance recoverable as of end of period 2,791,297 2,372,221 1,586,630 Gross reserves as of end of period $ 9,384,349 $ 6,076,271 $ 5,080,408 (1) Represents the fair value of TMR's reserves for claims and claim expenses, net of reinsurance recoverables, acquired at March 22, 2019. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. (2) Reflects the impact of the foreign exchange revaluation of net reserves denominated in non-U.S. dollars as at the balance sheet date. The Company’s reserving methodology for each line of business uses a loss reserving process that calculates a point estimate for its ultimate settlement and administration costs for claims and claim expenses. The Company does not calculate a range of estimates and does not discount any of its reserves for claims and claim expenses. The Company uses this point estimate, along with paid claims and case reserves, to record its best estimate of additional case reserves and IBNR in its consolidated financial statements. Under GAAP, the Company is not permitted to establish estimates for catastrophe claims and claim expense reserves until an event occurs that gives rise to a loss. Reserving for reinsurance claims involves other uncertainties, such as the dependence on information from ceding companies, the time lag inherent in reporting information from the primary insurer to the Company or to the Company’s ceding companies, and differing reserving practices among ceding companies. The information received from ceding companies is typically in the form of bordereaux, broker notifications of loss and/or discussions with ceding companies or their brokers. This information may be received on a monthly, quarterly or transactional basis and normally includes paid claims and estimates of case reserves. The Company sometimes also receives an estimate or provision for IBNR. This information is often updated and adjusted from time to time during the loss settlement period as new data or facts in respect of initial claims, client accounts, industry or event trends may be reported or emerge in addition to changes in applicable statutory and case laws. The Company’s estimates of losses from large events are based on factors including currently available information derived from claims information from certain customers and brokers, industry assessments of losses from the events, proprietary models, and the terms and conditions of the Company’s contracts. The uncertainty of the Company’s estimates for large events is also impacted by the preliminary nature of the information available, the magnitude and relative infrequency of the events, the expected duration of the respective claims development period, inadequacies in the data provided to the relevant date by industry participants and the potential for further reporting lags or insufficiencies; and in certain large events, significant uncertainty as to the form of the claims and legal issues, under the relevant terms of insurance and reinsurance contracts. In addition, a significant portion of the net claims and claim expenses associated with certain large events can be concentrated with a few large clients and therefore the loss estimates for these events may vary significantly based on the claims experience of those clients. The contingent nature of business interruption and other exposures will also impact losses in a meaningful way, which may give rise to significant complexity in respect of claims handling, claims adjustment and other coverage issues, over time. Given the magnitude of certain events, there can be meaningful uncertainty regarding total covered losses for the insurance industry and, accordingly, several of the key assumptions underlying the Company's loss estimates. Loss reserve estimation in respect of the Company's retrocessional contracts poses further challenges compared to directly assumed reinsurance. In addition, the Company’s actual net losses from these events may increase if the Company’s reinsurers or other obligors fail to meet their obligations. Because of the inherent uncertainties discussed above, the Company has developed a reserving philosophy that attempts to incorporate prudent assumptions and estimates, and the Company has generally experienced favorable net development on prior accident years net claims and claim expenses in the last several years. However, there is no assurance that this favorable development on prior accident years net claims and claim expenses will occur in future periods. The Company establishes a provision for unallocated loss adjustment expenses ("ULAE") when the related reserve for claims and claim expenses is established. ULAE are expenses that cannot be associated with a specific claim but are related to claims paid or in the process of settlement, such as internal costs of the claims function, and are included in the reserve for claims and claim expenses. The determination of the ULAE provision is subject to judgment. The Company reevaluates its actuarial reserving techniques on a periodic basis. Typically, the quarterly review procedures include reviewing paid and reported claims in the most recent reporting period, reviewing the development of paid and reported claims from prior periods, and reviewing the Company’s overall experience by underwriting year and in the aggregate. The Company monitors its expected ultimate claims and claim expense ratios and expected claims reporting assumptions on a quarterly basis and compares them to its actual experience. These actuarial assumptions are generally reviewed annually, based on input from the Company’s actuaries, underwriters, claims personnel and finance professionals, although adjustments may be made more frequently if needed. Assumption changes are made to adjust for changes in the pricing and terms of coverage the Company provides, changes in industry results for similar business, as well as its actual experience to the extent the Company has enough data to rely on its own experience. If the Company determines that adjustments to an earlier estimate are appropriate, such adjustments are recorded in the period in which they are identified. Incurred and Paid Claims Development and Reserving Methodology The information provided herein about incurred and paid accident year claims development for the years ended prior to December 31, 2019 on a consolidated basis and by segment is presented as supplementary information. The Company has applied a retrospective approach with respect to its acquisitions, presenting all relevant historical information for all periods presented. In addition, included in the incurred claims and claim expenses and cumulated paid claims and claim expenses tables below is a reconciling item that represents the unamortized balance of fair value adjustments recorded in connection with the acquisitions of Platinum and TMR, respectively, to reflect an increase in net claims and claim expenses due to the addition of a market based risk margin that represented the cost of capital required by a market participant to assume the net claims and claim expenses of Platinum and TMR, partially offset by a decrease from discounting in connection with the acquisitions of Platinum and TMR, to reflect the time value of money. For incurred and paid accident year claims denominated in foreign currency, the Company used the current year-end balance sheet foreign exchange rate for all periods provided, thereby eliminating the effects of changes in foreign currency translation rates from the incurred and paid accident year claims development information included in the tables below. The following table details the Company’s consolidated incurred claims and claim expenses and cumulative paid claims and claim expenses as of December 31, 2019 , net of reinsurance, as well as IBNR plus ACR included within the net incurred claims amounts. Incurred claims and claim expenses, net of reinsurance For the year ended December 31, At December 31, 2019 Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 IBNR and ACR (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 1,131,892 $ 1,105,041 $ 1,048,747 $ 1,033,341 $ 1,045,727 $ 1,037,725 $ 1,045,490 $ 1,043,565 $ 1,015,540 $ 1,052,931 $ 60,342 2011 — 1,989,024 1,926,506 1,827,258 1,768,793 1,738,452 1,698,378 1,683,614 1,678,015 1,664,869 55,191 2012 — — 1,138,018 1,021,668 958,139 927,438 891,981 894,168 901,049 907,212 48,297 2013 — — — 912,545 861,093 810,934 761,033 737,158 718,563 699,767 43,792 2014 — — — — 1,024,813 997,906 990,050 966,802 948,264 953,904 114,985 2015 — — — — — 1,171,023 1,156,856 1,175,927 1,145,983 1,133,632 131,005 2016 — — — — — — 1,401,451 1,458,767 1,432,001 1,426,575 251,952 2017 — — — — — — — 2,940,713 2,724,795 2,632,396 731,975 2018 — — — — — — — — 2,198,980 2,338,291 940,346 2019 — — — — — — — — — 2,280,044 1,764,899 Total $ 15,089,621 $ 4,142,784 Cumulative paid claims and claim expenses, net of reinsurance For the year ended December 31, Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 146,890 $ 334,347 $ 518,162 $ 603,060 $ 670,935 $ 746,454 $ 859,745 $ 892,480 $ 912,776 $ 928,552 2011 — 311,906 728,464 1,143,829 1,330,492 1,449,060 1,493,174 1,530,030 1,550,195 1,565,359 2012 — — 267,764 416,808 522,264 596,634 647,618 721,942 752,614 783,106 2013 — — — 131,829 340,652 434,508 496,380 554,686 587,978 615,463 2014 — — — — 230,826 432,761 554,398 630,417 691,774 741,844 2015 — — — — — 262,085 495,119 662,001 781,622 879,950 2016 — — — — — — 286,317 623,440 826,502 971,424 2017 — — — — — — — 745,098 1,067,481 1,371,477 2018 — — — — — — — — 587,619 804,566 2019 — — — — — — — — — 284,842 Total $ 8,946,583 Outstanding liabilities from accident year 2009 and prior, net of reinsurance 270,317 Claims and claim expenses, net of reinsurance, from the Company's former Bermuda-based insurance operations 229 Adjustment for unallocated claim expenses 51,876 Unamortized fair value adjustments recorded in connection with acquisitions (69,219 ) Liability for claims and claim expense, net of reinsurance, associated with RenaissanceRe UK 196,811 Liability for claims and claim expenses, net of reinsurance $ 6,593,052 Property Segment Within the Property segment, the Company principally writes property catastrophe excess of loss reinsurance contracts to insure insurance and reinsurance companies against natural and man-made catastrophes. Under these contracts, the Company indemnifies an insurer or reinsurer when its aggregate paid claims and claim expenses from a single occurrence of a covered peril exceeds the attachment point specified in the contract, up to an amount per loss specified in the contract. The Company's most significant exposure is to losses from hurricanes, earthquakes and other windstorms, although the Company is also exposed to claims arising from other catastrophes, such as tsunamis, winter storms, freezes, floods, fires, tornadoes, explosions and acts of terrorism. The Company's predominant exposure under such coverage is to property damage. However, other risks, including business interruption and other non-property losses, may also be covered under the Company's catastrophe contracts when arising from a covered peril. The Company's coverages are offered on either a worldwide basis or are limited to selected geographic areas. Coverage can also vary from “all property” perils to limited coverage on selected perils, such as “earthquake only” coverage. The Company also enters into retrocessional contracts that provide property catastrophe coverage to other reinsurers or retrocedants. This coverage is generally in the form of excess of loss retrocessional contracts and may cover all perils and exposures on a worldwide basis or be limited in scope to selected geographic areas, perils and/or exposures. The exposures the Company assumes from retrocessional business can change within a contract term as the underwriters of a retrocedant may alter their book of business after the retrocessional coverage has been bound. The Company also offers dual trigger reinsurance contracts which require the Company to pay claims based on claims incurred by insurers and reinsurers in addition to the estimate of insured industry losses as reported by referenced statistical reporting agencies. Also included in the Property segment is property per risk, property (re)insurance, binding facilities and regional U.S. multi-line reinsurance. The Company's predominant exposure under such coverage is to property damage. However, other risks, including business interruption and other non-property losses, may also be covered when arising from a covered peril. The Company's coverages are offered on either a worldwide basis or are limited to selected geographic areas. The exposures assumed from retrocessional business can change within a contract term as the underwriters of a retrocedant may alter their book of business after the retrocessional coverage has been bound. The Company offers these products principally through proportional coverage. In a proportional reinsurance arrangement (also referred to as quota share reinsurance or pro rata reinsurance), the reinsurer shares a proportional part of the original premiums and losses of the reinsured. Claims and claim expenses in the Company's Property segment are generally characterized by loss events of low frequency and high severity. Initial reporting of paid and incurred claims in general, tends to be relatively prompt. The Company considers this business “short-tail” as compared to the reporting of claims for “long-tail” products, which tends to be slower. However, the timing of claims payment and reporting also varies depending on various factors, including: whether the claims arise under reinsurance of primary insurance companies or reinsurance of other reinsurance companies; the nature of the events (e.g., hurricanes, earthquakes or terrorism); the geographic area involved; post-event inflation which may cause the cost to repair damaged property to increase significantly from current estimates, or for property claims to remain open for a longer period of time, due to limitations on the supply of building materials, labor and other resources; complex policy coverage and other legal issues; and the quality of each client’s claims management and reserving practices. Management’s judgments regarding these factors are reflected in the Company's reserve for claims and claim expenses. Reserving for most of the Company's Property segment generally does not involve the use of traditional actuarial techniques. Rather, claims and claim expense reserves are estimated by management after a catastrophe occurs by completing an in-depth analysis of the individual contracts which may potentially be impacted by the catastrophic event. The in-depth analysis generally involves: 1) estimating the size of insured industry losses from the catastrophic event; 2) reviewing reinsurance contract portfolios to identify contracts which are exposed to the catastrophic event; 3) reviewing information reported by customers and brokers; 4) discussing the event with customers and brokers; and 5) estimating the ultimate expected cost to settle all claims and administrative costs arising from the catastrophic event on a contract-by-contract basis and in aggregate for the event. Once an event has occurred, during the then current reporting period, the Company records its best estimate of the ultimate expected cost to settle all claims arising from the event. The Company's estimate of claims and claim expense reserves is then determined by deducting cumulative paid losses from its estimate of the ultimate expected loss for an event. The Company’s estimate of IBNR is determined by deducting cumulative paid losses, case reserves and additional case reserves from its estimate of the ultimate expected loss for an event. Once the Company receives a valid notice of loss or payment request under a catastrophe reinsurance contract, it is generally able to process and pay such claims promptly. Because the events from which claims arise under policies written within the Property segment are typically prominent, public occurrences such as hurricanes and earthquakes, the Company is often able to use independent reports as part of its loss reserve estimation process. The Company also reviews catastrophe bulletins published by various statistical reporting agencies to assist in determining the size of the industry loss, although these reports may not be available for some time after an event. For smaller events including localized severe weather events such as windstorms, hail, ice, snow, flooding, freezing and tornadoes, which are not necessarily prominent, public occurrences, the Company initially places greater reliance on catastrophe bulletins published by statistical reporting agencies to assist in determining what events occurred during the reporting period than the Company does for large events. This includes reviewing catastrophe bulletins published by Property Claim Services (“PCS”) for U.S. catastrophes. The Company sets its initial estimates of reserves for claims and claim expenses for these smaller events based on a combination of its historical market share for these types of losses and the estimate of the total insured industry property losses as reported by statistical reporting agencies, although management may make significant adjustments based on the Company's current exposure to the geographic region involved as well as the size of the loss and the peril involved. This approach supplements the Company's approach for estimating losses for larger catastrophes, which as discussed above, includes discussions with brokers and ceding companies and reviewing individual contracts impacted by the event. Approximately one year from the date of loss for these small events, the Company typically estimates IBNR for these events by using the paid Bornhuetter-Ferguson actuarial method. The loss development factors for the paid Bornhuetter-Ferguson actuarial method are selected based on a review of the Company's historical experience. There were no significant changes to the Company's paid loss development factors over the last three years. In general, reserves for the Company's more recent reinsured catastrophic events are subject to greater uncertainty and, therefore, greater potential variability, and are likely to experience material changes from one period to the next. This is due to the uncertainty as to the size of the industry losses from the event, uncertainty as to which contracts have been exposed to the catastrophic event, uncertainty due to complex legal and coverage issues that can arise out of large or complex catastrophic events, and uncertainty as to the magnitude of claims incurred by the Company's customers. As the Company's claims age, more information becomes available and the Company believes its estimates become more certain. The following table details the Company’s Property segment incurred claims and claim expenses and cumulative paid claims and claim expenses as of December 31, 2019 , net of reinsurance, as well as IBNR plus ACR included within the net incurred claims amounts. Incurred claims and claim expenses, net of reinsurance For the year ended December 31, At December 31, 2019 Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 IBNR and ACR (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 720,159 $ 681,287 $ 636,962 $ 657,719 $ 691,473 $ 696,844 $ 706,258 $ 708,343 $ 681,435 $ 731,179 $ 50,422 2011 — 1,559,069 1,491,770 1,422,659 1,393,110 1,369,567 1,338,187 1,333,982 1,321,137 1,302,141 24,335 2012 — — 559,946 429,425 395,203 375,098 356,310 344,535 336,719 331,865 12,351 2013 — — — 317,258 287,694 265,570 240,945 228,622 224,748 222,939 1,092 2014 — — — — 306,731 283,608 270,618 265,820 264,754 265,229 4,554 2015 — — — — — 368,766 334,572 317,865 307,088 301,733 11,672 2016 — — — — — — 445,532 458,525 443,135 432,269 53,990 2017 — — — — — — — 1,640,129 1,446,566 1,348,260 295,210 2018 — — — — — — — — 945,829 1,054,884 273,477 2019 — — — — — — — — — 1,000,190 719,847 Total $ 6,990,689 $ 1,446,950 Cumulative paid claims and claim expenses, net of reinsurance For the year ended December 31, Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 104,859 $ 230,552 $ 345,574 $ 401,977 $ 450,624 $ 481,489 $ 581,160 $ 595,131 $ 612,013 $ 623,231 2011 — 262,987 590,346 965,668 1,121,374 1,207,136 1,230,503 1,252,204 1,257,516 1,264,414 2012 — — 165,850 205,567 253,699 280,195 291,027 305,627 308,822 313,976 2013 — — — 80,083 155,459 191,181 206,376 213,351 216,176 219,231 2014 — — — — 106,618 184,140 222,509 234,144 241,139 247,663 2015 — — — — — 126,831 215,134 249,182 268,545 279,165 2016 — — — — — — 119,908 258,355 324,296 350,646 2017 — — — — — — — 534,097 660,491 824,443 2018 — — — — — — — — 432,201 450,125 2019 — — — — — — — — — 159,585 Total $ 4,732,479 Outstanding liabilities from accident year 2009 and prior, net of reinsurance 4,283 Adjustment for unallocated claim expenses 19,339 Unamortized fair value adjustments recorded in connection with acquisitions (10,606 ) Liability for claims and claim expense, net of reinsurance, associated with RenaissanceRe UK 17,536 Liability for claims and claim expenses, net of reinsurance $ 2,288,762 Casualty and Specialty Segment The Company offers its casualty and specialty reinsurance products principally on a proportional basis, and it also provides excess of loss coverage. The Company offers casualty and specialty reinsurance products to insurance and reinsurance companies and provides coverage for specific geographic regions or on a worldwide basis. Principally all of the business is reinsurance, although the Company also writes insurance business. As with the Company's Property segment, its Casualty and Specialty segment reinsurance contracts can include coverage for relatively large limits or exposures. As a result, the Company's casualty and specialty reinsurance business can be subject to significant claims volatility. In periods of low claims frequency or severity, the Company's results will generally be favorably impacted while in periods of high claims frequency or severity the Company's results will generally be negatively impacted. The Company has accepted a wide range of proportional risks, facilitating the Company's efforts to expand its product offerings. While the Company remains focused on underwriting discipline, and seeks to remain focused on opportunities amenable to stochastic representation and supported by strong data and analytics, the Company's expanded casualty and specialty product suite, may pose new, unmodelled or unforeseen risks for which the Company may not be adequately compensated and may also result in a higher level of attritional claims and claim expenses and the potential for reserve development, either adverse or favorable. The Company's processes and methodologies in respect of loss estimation for the coverages offered through its Casualty and Specialty segment differ from those used for its Property segment. For example, the Company's casualty and specialty coverages are more likely to be impacted by factors such as long-term inflation and changes in the social and legal environment, which the Company believes gives rise to greater uncertainty in its reserves for claims and claim expenses. Moreover, in many lines of business the Company does not have the benefit of a significant amount of its own historical experience and may have little or no related corporate reserving history in many of its newer or growing lines of business. The Company believes this makes its Casualty and Specialty segment reserving subject to greater uncertainty than its Property segment. The Company calculates multiple point estimates for claims and claim expense reserves using a variety of actuarial reserving techniques for many, but not all, of its classes of business for each underwriting year within the Casualty and Specialty segment. The Company does not believe that these multiple point estimates are, or should be considered, a range. Rather, the Company considers each class of business and determines the most appropriate point estimate for each underwriting year based on the characteristics of the particular class including: (1) loss development patterns derived from historical data; (2) the credibility of the selected loss development pattern; (3) the stability of the loss development patterns; (4) how developed the underwriting year is; and (5) the observed loss development of other underwriting years for the same class. The Company also considers other relevant factors, including: (1) historical ultimate loss ratios; (2) the presence of individual large losses; and (3) known occurrences that have not yet resulted in reported losses. The Company makes determinations of the most appropriate point estimate of loss for each class based on an evaluation of relevant information and do not ascribe any particular portion of the estimate to a particular factor or consideration. In addition, the Company believes that a review of individual contract information improves the loss estimates for some classes of business. When developing claims and claims expense reserves for the Company's Casualty and Specialty segment, it considers several actuarial techniques such as the expected loss ratio method, the Bornhuetter-Ferguson actuarial method and the paid and reported chain ladder actuarial method. For classes of business and underwriting years where the Company has limited historical claims experience, estimates of ultimate losses that are not related to a specific event are generally initially determined based on the loss ratio method applied to each underwriting year and to each class of business. Unless the Company has credible claims experience or unfavorable development, it generally selects an ultimate loss based on its initial view of the loss. The selected ultimate losses are determined by multiplying the initial expected loss ratio by the earned premium. The initial expected loss ratios are key inputs that involve management judgment and are based on a variety of factors, including: (1) contract by contract expected loss ratios developed during the Company’s pricing process; (2) historical loss ratios and combined ratios adjusted for rate change and trend; and (3) industry benchmarks for similar business. These judgments take into account management’s view of past, current and future factors that may influence ultimate losses, including: (1) market conditions; (2) changes in the business underwritten; (3) changes in timing of the emergence of claims; and (4) other factors that may influence ultimate loss ratios and losses. The determination of when reported losses are sufficient and credible to warrant selection of an ultimate loss ratio different from the initial expected loss ratios also requires judgment. The Company generally makes adjustments for reported loss experience indicating unfavorable variances from initial expected loss ratios sooner than reported loss experience indicating favorable variances. This is because the reporting of losses in excess of expectations tends to have greater credibility than an absence or lower than expected level of reported losses. Over time, as a greater number of claims are reported and the credibility of reported losses improves, actuarial estimates of IBNR are typically based on the Bornhuetter-Ferguson actuarial method or the reported chain ladder actuarial method. The Bornhuetter-Ferguson method allows for greater weight to be applied to expected results in periods where little or no actual experience is available, and, hence, is less susceptible to the potential pitfall of being excessively swayed by one year or one quarter of actual paid and/or reported loss data, compared to the chain ladder actuarial method. The Bornhuetter-Ferguson method uses the initial expected loss ratio to estimate IBNR, and it assumes that past experience is not fully representative of the future. As the Company’s reserves for claims and claim expenses age, and actual claims experience becomes available, this method places less weight on expected experience and places more weight on actual experience. This experience, which represents the difference between expected reported claims and actual reported claims, is reflected in the respective reporting period as a change in estimate. The utilization of the Bornhuetter-Ferguson method requires the Company to estimate an expected ultimate claims and claim expense ratio and select an expected loss reporting pattern. The Company selects its estimates of the expected ultimate claims and claim expense ratios as described above and selects its expected loss reporting patterns by utilizing actuarial analysis, including management’s judgment, and historical patterns of paid losses and reporting of case reserves to the Company, as well as industry loss development patterns. The estimated expected claims and claim expense ratio may be modified to the extent that reported losses at a given point in time differ from what would be expected based on the selected loss reporting pattern. The reported chain ladder actuarial method utilizes actual reported losses and a loss development pattern to determine an estimate of ultimate losses that is independent of the initial expected ultimate loss ratio and earned premium. The Company believes this technique is most appropriate when there are a large number of reported losses with significant statistical credibi

Debt and Credit Facilities

Debt and Credit Facilities	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Debt and Credit Facilities	DEBT AND CREDIT FACILITIES Debt Obligations A summary of the Company’s debt obligations on its consolidated balance sheets is set forth below: December 31, 2019 December 31, 2018 Fair Value Carrying Value Fair Value Carrying Value 3.600% Senior Notes due 2029 $ 424,920 $ 391,475 $ — $ — 3.450% Senior Notes due 2027 314,070 296,292 283,680 295,797 3.700% Senior Notes due 2025 318,567 298,057 292,557 297,688 5.750% Senior Notes due 2020 251,030 249,931 255,938 249,602 4.750% Senior Notes due 2025 (DaVinciRe) (1) 160,031 148,350 142,539 148,040 $ 1,468,618 $ 1,384,105 $ 974,714 $ 991,127 (1) RenaissanceRe owns a noncontrolling economic interest in its joint venture DaVinciRe. Because RenaissanceRe controls a majority of DaVinciRe’s outstanding voting rights, the consolidated financial statements of DaVinciRe are included in the consolidated financial statements of RenaissanceRe. However, RenaissanceRe does not guarantee or provide credit support for DaVinciRe and RenaissanceRe’s financial exposure to DaVinciRe is limited to its investment in DaVinciRe’s shares and counterparty credit risk arising from reinsurance transactions. 3.600% Senior Notes Due 2029 On April 2, 2019, RenaissanceRe issued $400.0 million principal amount of its 3.600% Senior Notes due April 15, 2029 , with interest on the notes payable on April 15 and October 15 of each year, commencing on October 15, 2019. The notes are redeemable at the applicable redemption price, subject to the terms described in the indenture for the notes. However, the notes may not be redeemed prior to April 15, 2022 without approval from the Bermuda Monetary Authority (the “BMA”) and may not be redeemed at any time prior to their maturity if enhanced capital requirements, as established by the BMA, would be breached immediately before or after giving effect to the redemption of such notes, unless, in each case, RenaissanceRe replaces the capital represented by the notes to be redeemed with capital having equal or better capital treatment as the notes under applicable BMA rules. The notes contain various covenants including limitations on mergers and consolidations, and restrictions as to the disposition of, and the placing of liens on, the stock of designated subsidiaries. The net proceeds from this offering were used to repay, in full, the $200.0 million outstanding under the Company’s revolving credit facility at March 31, 2019, which the Company used to partially fund the purchase price for the TMR Stock Purchase, and the remainder of the net proceeds was used for general corporate purposes. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. 3.450% Senior Notes due 2027 of RenaissanceRe Finance Inc. On June 29, 2017 , RenaissanceRe Finance Inc. (“RenaissanceRe Finance”) issued $300.0 million principal amount of its 3.450% Senior Notes due July 1, 2027 , with interest on the notes payable on July 1 and January 1 of each year. The notes are fully and unconditionally guaranteed by RenaissanceRe and may be redeemed by RenaissanceRe Finance prior to maturity, subject to the payment of a “make-whole” premium if the notes are redeemed prior to April 1, 2027 . The notes contain various covenants, including limitations on mergers and consolidations, and restrictions as to the disposition of, and the placing of liens on, stock of designated subsidiaries. 3.700% Senior Notes due 2025 of RenaissanceRe Finance On March 24, 2015 , RenaissanceRe Finance issued $300.0 million principal amount of its 3.700% Senior Notes due April 1, 2025 , with interest on the notes payable on April 1 and October 1 of each year. The notes are fully and unconditionally guaranteed by RenaissanceRe and may be redeemed by RenaissanceRe Finance prior to maturity, subject to the payment of a “make-whole” premium if the notes are redeemed prior to January 1, 2025. The notes contain various covenants, including limitations on mergers and consolidations, and restrictions as to the disposition of, and the placing of liens on, stock of designated subsidiaries. The net proceeds from the offering of the notes (together with cash on hand) were applied by RenaissanceRe to repay in full a $300.0 million bridge loan that Barclays Bank PLC provided to RenaissanceRe on February 25, 2015 in order to finance a portion of the cash consideration paid by RenaissanceRe in connection with the acquisition of Platinum. 5.75% Senior Notes due 2020 of RenRe North America Holdings Inc. and RenaissanceRe Finance On March 17, 2010, RenRe North America Holdings Inc. (“RRNAH”) issued $250.0 million principal amount of its 5.75% Senior Notes due March 15, 2020 (the “RRNAH Notes”), with interest on the notes payable on March 15 and September 15 of each year. RenaissanceRe Finance became a co-obligor of the notes as of July 3, 2015. The notes, which are senior obligations, are fully and unconditionally guaranteed by RenaissanceRe and may be redeemed prior to maturity, subject to the payment of a “make-whole” premium. The notes contain various covenants, including limitations on mergers and consolidations, and restrictions as to the disposition of, and the placing of liens on, stock of designated subsidiaries. Series B 7.50% Notes due 2017 of Platinum Underwriters Finance, Inc. On November 2, 2005, Platinum Underwriters Finance, Inc. (“Platinum Finance”) issued $250.0 million principal amount of its Series B 7.50% Notes due June 1, 2017 (the “Platinum Finance Notes”). On June 1, 2017, the Platinum Finance Notes matured and the Company repaid the aggregate principal amount of $250.0 million plus applicable accrued interest in full. Platinum Finance was subsequently dissolved on November 30, 2017. Interest on the Platinum Finance Notes was payable on June 1 and December 1 of each year. The Platinum Finance Notes, which were senior obligations, were fully and unconditionally guaranteed by RenaissanceRe. DaVinciRe Senior Notes On May 4, 2015 , DaVinciRe issued $150.0 million principal amount of its 4.750% Senior Notes due May 1, 2025 , with interest on the notes payable on May 1 and November 1, commencing with November 1, 2015 (the “DaVinciRe Senior Notes”). The DaVinciRe Senior Notes, which are senior obligations, may be redeemed prior to maturity, subject to the payment of a “make-whole” premium if the notes are redeemed before February 1, 2025. The DaVinciRe Senior Notes contain various covenants including restrictions as to the disposition of, and the placing of liens on, the stock of designated subsidiaries, limitations on mergers, amalgamations and consolidations, limitations on third-party investor redemptions, a leverage covenant and a covenant to maintain certain ratings. The net proceeds from this offering were used to repay, in full, $100.0 million outstanding under the loan agreement, dated as of March 30, 2011, between DaVinciRe and RenaissanceRe, and the remainder of the net proceeds were used for general corporate purposes. Scheduled Debt Maturity The following table sets forth the scheduled maturity of the Company’s aggregate amount of its debt obligation reflected on its consolidated balance sheet at December 31, 2019 : 2020 $ 250,000 2021 — 2022 — 2023 — 2024 — After 2024 1,150,000 Unamortized discount and debt issuance expenses (15,895 ) $ 1,384,105 Credit Facilities The outstanding amounts issued or drawn under each of the Company’s significant credit facilities is set forth below: At December 31, 2019 Issued or Drawn Revolving Credit Facility (1) $ — Bilateral Letter of Credit Facilities Secured 298,063 Unsecured 381,770 Funds at Lloyd’s Letter of Credit Facility 290,000 TMR Letters of Credit (2) 140,923 $ 1,110,756 (1) At December 31, 2019 , no amounts were issued or drawn under this facility. (2) These letters of credit were transferred to us in connection with the acquisition of TMR. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. Revolving Credit Facility RenaissanceRe, Renaissance Reinsurance, RenaissanceRe Specialty U.S., Renaissance Reinsurance U.S. and RenaissanceRe Europe are parties to a second amended and restated credit agreement dated November 9, 2018 (as amended, the “Revolving Credit Agreement”) with various banks, financial institutions and Wells Fargo Bank, National Association (“Wells Fargo”) as administrative agent, which amended and restated a previous credit agreement. The Revolving Credit Agreement provides for a revolving commitment to RenaissanceRe of $500.0 million , with a right, subject to satisfying certain conditions, to increase the size of the facility to $750.0 million . Amounts borrowed under the Revolving Credit Agreement bear interest at a rate selected by RenaissanceRe equal to the Base Rate or LIBOR (each as defined in the Revolving Credit Agreement) plus a margin. In addition to revolving loans, the Revolving Credit Agreement provides that the entire facility will also be available for the issuance of standby letters of credit, subject to the terms and conditions set forth therein, and swingline loans, which are capped at $50.0 million for each of the swingline lenders. At December 31, 2019 , RenaissanceRe had $Nil outstanding under the Revolving Credit Agreement. The Revolving Credit Agreement contains representations, warranties and covenants customary for bank loan facilities of this type, including limits on the ability of RenaissanceRe and its subsidiaries to merge, consolidate, sell a substantial amount of assets, incur liens and declare or pay dividends under certain circumstances. The Revolving Credit Agreement also contains certain financial covenants which generally provide that the ratio of consolidated debt to capital shall not exceed 0.35 : 1 and that the consolidated net worth of RenaissanceRe shall equal or exceed approximately $2.9 billion . The net worth requirement is recalculated effective as of the end of each fiscal year. If certain events of default occur, in some circumstances the lenders’ obligations to make loans may be terminated and the outstanding obligations of RenaissanceRe under the Revolving Credit Agreement may be accelerated. The scheduled commitment maturity date of the Revolving Credit Agreement is November 9, 2023. RRNAH and RenaissanceRe Finance guarantee RenaissanceRe’s obligations under the Revolving Credit Agreement. Subject to certain exceptions, additional subsidiaries of RenaissanceRe are required to become guarantors if such subsidiaries issue or incur certain types of indebtedness. Bilateral Letter of Credit Facilities Uncommitted, Secured Standby Letter of Credit Facility with Wells Fargo RenaissanceRe and certain of its subsidiaries and affiliates, including Renaissance Reinsurance, DaVinci, Renaissance Reinsurance U.S. and RenaissanceRe Europe are parties to an Amended and Restated Standby Letter of Credit Agreement dated June 21, 2019 with Wells Fargo, which provides for a secured, uncommitted facility under which letters of credit may be issued from time to time for the respective accounts of the subsidiaries. Pursuant to the agreement, the applicants may request secured letter of credit issuances, and also have an option to request the issuance of up to $25.0 million of unsecured letters of credit (outstanding on such request date). RenaissanceRe has unconditionally guaranteed the payment obligations of the applicants other than DaVinci. The agreement contains representations, warranties and covenants that are customary for facilities of this type. Under the agreement, each applicant is required to pledge eligible collateral having a value sufficient to cover all of its obligations under the agreement with respect to secured letters of credit issued for its account. In the case of an event of default under the agreement, Wells Fargo may exercise certain remedies, including conversion of collateral of a defaulting applicant into cash. At December 31, 2019 , there were $31.5 million of secured letters of credit outstanding and $Nil of unsecured letters of credit outstanding under this agreement. Secured Letter of Credit Facility with Citibank Europe Certain subsidiaries and affiliates of RenaissanceRe, including Renaissance Reinsurance, DaVinci, Renaissance Reinsurance of Europe, RenaissanceRe Specialty U.S., Renaissance Reinsurance U.S. and RenaissanceRe Europe, are parties to a facility letter, dated September 17, 2010, as amended, with Citibank Europe plc (“Citibank Europe”), pursuant to which Citibank Europe has established a letter of credit facility under which Citibank Europe provides a commitment to issue letters of credit for the accounts of the participants in multiple currencies. The aggregate commitment amount is $300.0 million , subject to a sublimit of $25.0 million for letters of credit issued for the account of Renaissance Reinsurance U.S. The letter of credit facility is scheduled to expire on December 31, 2021. At all times during which it is a party to the facility, each participant is obligated to pledge to Citibank Europe securities with a value that equals or exceeds the aggregate face amount of its then-outstanding letters of credit. In the case of an event of default under the facility with respect to a participant, Citibank Europe may exercise certain remedies, including terminating its commitment to such participant and taking certain actions with respect to the collateral pledged by such participant (including the sale thereof). In the facility letter, each participant makes representations and warranties that are customary for facilities of this type and agrees that it will comply with certain informational and other undertakings. At December 31, 2019 , $266.5 million aggregate face amount of letters of credit was outstanding and, subject to the sublimits described above, $33.5 million remained unused and available to the participants under this facility. Uncommitted, Unsecured Letter of Credit Facility with Citibank Europe Renaissance Reinsurance, RenaissanceRe Specialty U.S., Renaissance Reinsurance U.S., RenaissanceRe Europe and RenaissanceRe UK are parties to a Master Agreement for Issuance of Payment Instruments and a Facility Letter for Issuance of Payment Instruments with Citibank Europe dated March 22, 2019, as amended, which established an uncommitted, unsecured letter of credit facility pursuant to which Citibank Europe or one of its correspondents may issue standby letters of credit or similar instruments in multiple currencies for the account of one or more of the applicants. The obligations of the applicants under this facility are guaranteed by RenaissanceRe. Pursuant to the master agreement, each applicant makes representations and warranties that are customary for facilities of this type and agrees that it will comply with certain informational and other customary undertakings. The master agreement contains events of default customary for facilities of this type. In the case of an event of default under the facility, Citibank Europe may exercise certain remedies, including requiring that the relevant applicant pledge cash collateral in an amount equal to the maximum actual and contingent liability of the issuing bank under the letters of credit and similar instruments issued for such applicant under the facility, and taking certain actions with respect to the collateral pledged by such applicant (including the sale thereof). In addition, Citibank Europe may require that the relevant applicant pledge cash collateral if certain minimum ratings are not satisfied. At December 31, 2019 , the aggregate face amount of the payment instruments issued and outstanding under this facility was $270.7 million . Unsecured Letter of Credit Facility with Credit Suisse RenaissanceRe Europe and RenaissanceRe are parties to an amended and restated letter of credit facility agreement with Credit Suisse (Switzerland) Ltd. (“Credit Suisse”) dated March 22, 2019 which provides for a $125.0 million committed, unsecured letter of credit facility pursuant to which Credit Suisse (or any other fronting bank acting on behalf of Credit Suisse) may issue letters of credit or similar instruments in multiple currencies for the account of RenaissanceRe Europe. The obligations of RenaissanceRe Europe under the agreement are guaranteed by RenaissanceRe. The facility is scheduled to expire on December 21, 2022. In the agreement, RenaissanceRe Europe and RenaissanceRe make representations, warranties and covenants that are customary for facilities of this type, and agree to comply with certain informational and other customary undertakings. The agreement also contains certain financial covenants applicable to the RenaissanceRe, including the requirement to maintain the ratio of consolidated debt to capital of not more than 0.35 : 1 , to maintain a minimum consolidated net worth initially of approximately $3.0 billion , subject to an annual adjustment, and to maintain RenaissanceRe’s credit rating with S&P and A.M. Best of at least A-. The agreement contains events of default customary for facilities of this type. At any time on or after the occurrence of an event of default, Credit Suisse may exercise remedies, including canceling the commitment, requiring that RenaissanceRe Europe pledge cash collateral in an amount equal to the maximum liability of the issuing bank under the letters of credit and similar instruments issued under the agreement, and demanding that RenaissanceRe Europe procure the release by the beneficiaries of the letters of credit and similar instruments issued under the agreement. At December 31, 2019 , letters of credit issued by Credit Suisse under the agreement were outstanding in the face amount of $111.1 million . Funds at Lloyd’s Letter of Credit Facility Renaissance Reinsurance is party to a letter of credit facility with Bank of Montreal, Citibank Europe and ING Bank N.V. evidenced by an Amended and Restated Letter of Credit Reimbursement Agreement dated November 7, 2019, which provides for the issuance of letters of credit to support business written by Renaissance Reinsurance’s Lloyd’s syndicate, Syndicate 1458. Effective November 7, 2019, the stated amount of the outstanding Funds at Lloyd’s letter of credit increased from $255.0 million to $290.0 million . Renaissance Reinsurance may request that the outstanding letter of credit be amended to increase the stated amount or that a new letter of credit denominated in U.S. dollars be issued, in an aggregate amount for all such increases or issuances not to exceed $140.0 million . The facility terminates four years from the date of notice from the lenders to the beneficiary of the letter of credit, unless extended. Generally, Renaissance Reinsurance is not required to post any collateral for letters of credit issued pursuant to this facility. However, following the occurrence of a partial collateralization event or a full collateralization event, as provided in the agreement, Renaissance Reinsurance is required to pledge eligible securities with a collateral value of at least 60% or 100% , respectively, of the aggregate amount of its then-outstanding letters of credit. The latest date upon which Renaissance Reinsurance will become obligated to collateralize the facility at 100% is December 31, 2020. In the agreement, Renaissance Reinsurance makes representations and warranties that are customary for facilities of this type and agrees that it will comply with certain informational undertakings and other covenants, including maintaining a minimum net worth. In the case of an event of default under the FAL facility, the lenders may exercise certain remedies, including declaring all outstanding obligations of Renaissance Reinsurance under the agreement and related credit documents due and payable and taking certain actions with respect to the collateral pledged by Renaissance Reinsurance (including the sale thereof). At December 31, 2019 , the face amount of the outstanding letter of credit issued under the FAL facility was $290.0 million . TMR Letters of Credit In connection with the acquisition of TMR, certain letters of credit were transferred to the Company, as follows: (a) Mizuho Bank, Ltd. issued certain letters of credit for the account of RenaissanceRe Europe pursuant to a Letter of Credit and Reimbursement Agreement, dated as of May 14, 2012, as previously amended, (b) The Bank of Tokyo-Mitsubishi UFJ Ltd., Düsseldorf Branch, issued certain letters of credit for the account of RenaissanceRe Europe pursuant to a Committed Revolving Standby Letter of Credit Agreement, dated as of September 29, 2017, and (c) The Bank of Tokyo-Mitsubishi UFJ, Ltd. issued certain letters of credit for the account of RenaissanceRe UK pursuant to a Facility Letter, dated as of December 21, 2006. The parties have agreed that no new letters of credit will be issued under these facilities. Top Layer Re Renaissance Reinsurance is party to a collateralized letter of credit and reimbursement agreement in the amount of $37.5 million that supports the Company’s Top Layer Re joint venture. Renaissance Reinsurance is obligated to make a mandatory capital contribution of up to $50.0 million in the event that a loss reduces Top Layer Re’s capital below a specified level.

Noncontrolling Interests

Noncontrolling Interests	12 Months Ended
	Dec. 31, 2019
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest [Abstract]
Noncontrolling Interests	NONCONTROLLING INTERESTS A summary of the Company’s redeemable noncontrolling interests on its consolidated balance sheets is set forth below: December 31, December 31, Redeemable noncontrolling interest - DaVinciRe $ 1,435,581 $ 1,034,946 Redeemable noncontrolling interest - Medici 632,112 416,765 Redeemable noncontrolling interest - Vermeer 1,003,615 599,989 Redeemable noncontrolling interests $ 3,071,308 $ 2,051,700 A summary of the Company’s redeemable noncontrolling interests on its consolidated statements of operations is set forth below: Year ended December 31, 2019 2018 2017 Redeemable noncontrolling interest - DaVinciRe $ 127,084 $ 27,638 $ (134,860 ) Redeemable noncontrolling interest - Medici 25,759 13,926 2,578 Redeemable noncontrolling interest - Vermeer 48,626 (11 ) — Net income (loss) attributable to redeemable noncontrolling interests $ 201,469 $ 41,553 $ (132,282 ) Redeemable Noncontrolling Interest – DaVinciRe RenaissanceRe owns a noncontrolling economic interest in DaVinciRe; however, because RenaissanceRe controls a majority of DaVinciRe’s outstanding voting rights, the consolidated financial statements of DaVinciRe are included in the consolidated financial statements of the Company. The portion of DaVinciRe’s earnings owned by third parties is recorded in the consolidated statements of operations as net income attributable to redeemable noncontrolling interests. The Company’s noncontrolling economic ownership in DaVinciRe was 21.9% at December 31, 2019 ( 2018 - 22.1% ). DaVinciRe shareholders are party to a shareholders agreement which provides DaVinciRe shareholders, excluding RenaissanceRe, with certain redemption rights that enable each shareholder to notify DaVinciRe of such shareholder’s desire for DaVinciRe to repurchase up to half of such shareholder’s initial aggregate number of shares held, subject to certain limitations, such as limiting the aggregate of all share repurchase requests to 25% of DaVinciRe’s capital in any given year and satisfying all applicable regulatory requirements. If total shareholder requests exceed 25% of DaVinciRe’s capital, the number of shares repurchased will be reduced among the requesting shareholders pro-rata, based on the amounts desired to be repurchased. Shareholders desiring to have DaVinci repurchase their shares must notify DaVinciRe before March 1 of each year. The repurchase price will be based on GAAP book value as of the end of the year in which the shareholder notice is given, and the repurchase will be effective as of January 1 of the following year. The repurchase price is generally subject to a true-up for potential development on outstanding loss reserves after settlement of all claims relating to the applicable years. 2019 Effective June 1, 2019, DaVinciRe completed an equity capital raise of $349.2 million , comprised of $263.1 million from third-party investors and $86.1 million from RenaissanceRe. In addition, RenaissanceRe sold an aggregate of $11.6 million of its shares in DaVinciRe to a third-party investor. The Company’s noncontrolling economic ownership in DaVinciRe subsequent to these transactions was 21.9% , effective June 1, 2019. The Company expects its noncontrolling economic ownership in DaVinciRe to fluctuate over time. The activity in redeemable noncontrolling interest – DaVinciRe is detailed in the table below: Year ended December 31, 2019 2018 Beginning balance $ 1,034,946 $ 1,011,659 Redemption of shares from redeemable noncontrolling interests, net of adjustments (1,148 ) (4,351 ) Sale of shares to redeemable noncontrolling interests 274,699 — Net income attributable to redeemable noncontrolling interests 127,084 27,638 Ending balance $ 1,435,581 $ 1,034,946 Redeemable Noncontrolling Interest - Medici Medici is an exempted company incorporated under the laws of Bermuda and its objective is to seek to invest substantially all of its assets in various insurance-based investment instruments that have returns primarily tied to property catastrophe risk. RenaissanceRe owns a noncontrolling economic interest in Medici; however, because RenaissanceRe controls all of Medici’s outstanding voting rights, the financial statements of Medici are included in the consolidated financial statements of the Company. The portion of Medici’s earnings owned by third parties is recorded in the consolidated statements of operations as net income attributable to redeemable noncontrolling interests. Any shareholder may redeem all or any portion of its shares as of the last day of any calendar month, upon at least 30 calendar days’ prior irrevocable written notice to Medici. 2019 During 2019 , third-party investors subscribed for $237.0 million and redeemed $47.4 million of the participating, non-voting common shares of Medici. As a result of these net subscriptions, the Company’s noncontrolling economic ownership in Medici was 12.1% at December 31, 2019 . 2018 During 2018 , third-party investors subscribed for $208.5 million and redeemed $90.5 million of the participating, non-voting common shares of Medici. As a result of these net subscriptions, the Company’s noncontrolling economic ownership in Medici was 16.6% , at December 31, 2018 . The Company expects its noncontrolling economic ownership in Medici to fluctuate over time. The activity in redeemable noncontrolling interest – Medici is detailed in the table below: Year ended December 31, 2019 2018 Beginning balance $ 416,765 $ 284,847 Redemption of shares from redeemable noncontrolling interests, net of adjustments (47,401 ) (90,490 ) Sale of shares to redeemable noncontrolling interests 236,989 208,482 Net income attributable to redeemable noncontrolling interests 25,759 13,926 Ending balance $ 632,112 $ 416,765 Redeemable Noncontrolling Interest – Vermeer Vermeer is an exempted Bermuda reinsurer that provides capacity focused on risk remote layers in the U.S. property catastrophe market. Vermeer is managed by RUM in return for a management fee. The Company maintains majority voting control of Vermeer, while the sole third-party investor, PGGM, retains all of the economic benefits. The Company concluded that Vermeer is a VIE as it has voting rights that are not proportional to its participating rights, and the Company is the primary beneficiary. As a result, the Company consolidates Vermeer and all significant inter-company transactions have been eliminated. The portion of Vermeer’s earnings owned by PGGM is recorded in the consolidated statements of operations as net income attributable to redeemable noncontrolling interests. The Company has not provided any financial or other support to Vermeer that it was not contractually required to provide. 2019 During 2019 , PGGM subscribed for $355.0 million of the participating, non-voting common shares of Vermeer. 2018 During 2018, PGGM subscribed for $600.0 million of the participating, non-voting common shares of Vermeer and the Company subscribed for $1 thousand of all the voting, non-participating shares of Vermeer. The Company does not expect its noncontrolling economic ownership in Vermeer to fluctuate over time. The activity in redeemable noncontrolling interest – Vermeer is detailed in the table below: Year ended December 31, 2019 2018 Beginning balance $ 599,989 $ — Sale of shares to redeemable noncontrolling interest 355,000 600,000 Net income (loss) attributable to redeemable noncontrolling interest 48,626 (11 ) Ending balance $ 1,003,615 $ 599,989

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	VARIABLE INTEREST ENTITIES Upsilon RFO Upsilon RFO is a managed joint venture and a Bermuda domiciled SPI that was formed by the Company principally to provide additional capacity to the worldwide aggregate and per-occurrence retrocessional property catastrophe excess of loss market. The shareholders (other than the Class A shareholder) participate in substantially all of the profits or losses of Upsilon RFO while their shares remain outstanding. The shareholders (other than the Class A shareholder) indemnify Upsilon RFO against losses relating to insurance risk and therefore these shares have been accounted for as prospective reinsurance under FASB ASC Topic Financial Services - Insurance . Upsilon RFO is considered a VIE as it has insufficient equity capital to finance its activities without additional financial support. The Company is the primary beneficiary of Upsilon RFO as it has the power over the activities that most significantly impact the economic performance of Upsilon RFO and has the obligation to absorb expected losses and the right to receive expected benefits that could be significant to Upsilon RFO, in accordance with the accounting guidance. As a result, the Company consolidates Upsilon RFO and all significant inter-company transactions have been eliminated. Other than its equity investment in Upsilon RFO, the Company has not provided financial or other support to Upsilon RFO that it was not contractually required to provide. 2019 During 2019 , Upsilon RFO returned $279.2 million of capital to its investors, including $31.0 million to the Company. In addition, during 2019 , $618.7 million of Upsilon RFO non-voting preference shares were issued to new and existing investors, including $100.0 million to the Company. At December 31, 2019 , the Company’s participation in the risks assumed by Upsilon RFO was 16.5% . Payments for certain of the shares issued during 2019 that were received by the Company prior to January 1, 2019 were included in other liabilities on the Company’s consolidated balance sheet at December 31, 2018, and in other operating cash flows on the Company’s consolidated statements of cash flows for 2018. During 2019, in connection with the issuance of the non-voting preference shares of Upsilon RFO, other liabilities were reduced by this amount, and reinsurance balances payable were increased by an offsetting amount, with corresponding impacts to other operating cash flows and the change in reinsurance balances payable on the Company consolidated statements of cash flows for the year ended December 31, 2019. At December 31, 2019 , the Company’s consolidated balance sheet included total assets and total liabilities of Upsilon RFO of $3.1 billion and $3.1 billion , respectively ( December 31, 2018 - $2.2 billion and $2.2 billion , respectively). 2018 During 2018, $856.7 million of Upsilon RFO non-voting preference shares were issued to existing investors, including $109.8 million to the Company. At December 31, 2018, the Company’s participation in the risks assumed by Upsilon RFO was 14.0% . Payments for certain of the shares issued during 2018 that were received by the Company prior to January 1, 2018 were included in other liabilities on the Company’s consolidated balance sheet at December 31, 2017, and in other operating cash flows on the Company’s consolidated statements of cash flows for 2017. During 2018, in connection with the issuance of the non-voting preference shares of Upsilon RFO, other liabilities were reduced by this amount, and reinsurance balances payable were increased by an offsetting amount, with corresponding impacts to other operating cash flows and the change in reinsurance balances payable on the Company consolidated statements of cash flows for the year ended December 31, 2018. Refer to “Note 23 . Subsequent Events” for additional information related to Upsilon RFO’s non-voting preference shares subsequent to December 31, 2019 . Vermeer Vermeer is an exempted Bermuda reinsurer that provides capacity focused on risk remote layers in the U.S. property catastrophe market. Vermeer is considered a VIE as it has voting rights that are not proportional to its participating rights. The Company is the primary beneficiary of Vermeer as it has power over the activities that most significantly impact the economic performance of Vermeer and has the obligation to absorb expected losses and the right to receive expected benefits that could be significant to Vermeer, in accordance with the accounting guidance. The portion of Vermeer’s earnings owned by PGGM is recorded in the consolidated statements of operations as net income attributable to redeemable noncontrolling interests. Refer to “Note 10 . Noncontrolling Interests” for additional information regarding Vermeer. Other than the Company’s minimal equity investment, it has not provided any financial or other support to Vermeer that it was not contractually required to provide. At December 31, 2019 , the Company’s consolidated balance sheet included total assets and total liabilities of Vermeer of $1.0 billion and $23.2 million , respectively ( 2018 - $600.4 million and $0.4 million , respectively). In addition, the Company’s consolidated balance sheet included redeemable noncontrolling interests associated with Vermeer of $1.0 billion at December 31, 2019 ( 2018 - $600.0 million ). Mona Lisa Re Ltd. Mona Lisa Re Ltd. (“Mona Lisa Re”) is licensed as a Bermuda domiciled SPI to provide reinsurance capacity to subsidiaries of RenaissanceRe, namely Renaissance Reinsurance and DaVinci, through reinsurance agreements which will be collateralized and funded by Mona Lisa Re through the issuance of one or more series of principal-at-risk variable rate notes to third-party investors. Upon issuance of a series of notes by Mona Lisa Re, all of the proceeds from the issuance are deposited into collateral accounts, separated by series, to fund any potential obligation under the reinsurance agreements entered into with Renaissance Reinsurance and/or DaVinci underlying such series of notes. The outstanding principal amount of each series of notes generally will be returned to holders of such notes upon the expiration of the risk period underlying such notes, unless an event occurs which causes a loss under the applicable series of notes, in which case the amount returned will be reduced by such noteholder’s pro rata share of such loss, as specified in the applicable governing documents of such notes. In addition, holders of such notes are generally entitled to interest payments, payable quarterly, as determined by the applicable governing documents of each series of notes. The Company concluded that Mona Lisa Re meets the definition of a VIE as it does not have sufficient equity capital to finance its activities. The Company evaluated its relationship with Mona Lisa Re and concluded it does not have a variable interest in Mona Lisa Re. As a result, the financial position and results of operations of Mona Lisa Re are not consolidated by the Company. The Company has not provided financial or other support to Mona Lisa Re that it was not contractually required to provide. On July 6, 2018, all previously outstanding series of notes issued by Mona Lisa Re were redeemed and the proceeds were returned to the holders of such notes. At December 31, 2019 , the total assets and total liabilities of Mona Lisa Re were $6 thousand and $6 thousand , respectively ( 2018 - $41 thousand and $41 thousand , respectively). The only transactions related to Mona Lisa Re that are recorded in the Company’s consolidated financial statements are the ceded reinsurance agreements entered into by Renaissance Reinsurance and DaVinci which are accounted for as prospective reinsurance under FASB ASC Topic Financial Services - Insurance . Renaissance Reinsurance and DaVinci have together entered into ceded reinsurance contracts with Mona Lisa Re with gross premiums ceded of $Nil and $Nil , respectively, during 2019 ( 2018 - $0.2 million and $0.2 million , respectively, 2017 - $0.4 million and $0.4 million , respectively). In addition, Renaissance Reinsurance and DaVinci recognized ceded premiums earned related to the ceded reinsurance contracts with Mona Lisa Re of $Nil and $Nil , respectively, during 2019 ( 2018 - $0.2 million and $0.2 million , respectively, 2017 - $4.1 million and $2.9 million , respectively). Refer to “Note 23 . Subsequent Events” for additional information related to the issuance of principal-at-risk variable rate notes by Mona Lisa Re subsequent to December 31, 2019 . Fibonacci Re Fibonacci Re, a Bermuda-domiciled SPI, was formed to provide collateralized capacity to Renaissance Reinsurance and its affiliates. Upon issuance of a series of notes by Fibonacci Re, all of the proceeds from the issuance are deposited into collateral accounts, separated by series, to fund any potential obligation under the reinsurance agreements entered into with Renaissance Reinsurance underlying such series of notes. The outstanding principal amount of each series of notes generally is expected to be returned to holders of such notes upon the expiration of the risk period underlying such notes, unless an event occurs which causes a loss under the applicable series of notes, in which case the amount returned is expected to be reduced by such noteholder’s pro rata share of such loss, as specified in the applicable governing documents of such notes. In addition, holders of such notes are generally entitled to interest payments, payable quarterly, as determined by the applicable governing documents of each series of notes. RUM receives an origination and structuring fee in connection with the formation and operation of Fibonacci Re. The Company concluded that Fibonacci Re meets the definition of a VIE as it does not have sufficient equity capital to finance its activities. The Company evaluated its relationship with Fibonacci Re and concluded it is not the primary beneficiary of Fibonacci Re as it does not have power over the activities that most significantly impact the economic performance of Fibonacci Re. As a result, the Company does not consolidate the financial position or results of operations of Fibonacci Re. The only transactions related to Fibonacci Re that will be recorded in the Company’s consolidated financial statements will be the ceded reinsurance agreements entered into by Renaissance Reinsurance that are accounted for as prospective reinsurance under FASB ASC Topic Financial Services - Insurance, and the fair value of the participating notes owned by the Company. Other than its investment in the participating notes of Fibonacci Re, the Company has not provided financial or other support to Fibonacci Re that it was not contractually required to provide. The fair value of the Company’s investment in the participating notes of Fibonacci Re is included in other investments. Net of third-party investors, the fair value of the Company’s investment in Fibonacci Re was $0.4 million at December 31, 2019 ( 2018 - $6.0 million ). Renaissance Reinsurance entered into ceded reinsurance contracts with Fibonacci Re with ceded premiums of $0.1 million and ceded premiums earned of $0.1 million during 2019 ( 2018 - $9.1 million and $10.0 million , respectively). During 2019 , Renaissance Reinsurance ceded $7.5 million of net claims and claim expenses to Fibonacci Re ( 2018 - $Nil ) and as of December 31, 2019 had a net reinsurance recoverable of $7.5 million from Fibonacci Re ( December 31, 2018 - $Nil ). Langhorne The Company and Reinsurance Group of America, Incorporated formed Langhorne, an initiative to source third-party capital to support reinsurers targeting large in-force life and annuity blocks. In connection with Langhorne, as of December 31, 2019 the Company has invested $1.7 million in Langhorne Holdings ( 2018 - $1.3 million ), a company that owns and manages certain reinsurance entities within Langhorne. In addition, as of December 31, 2019 the Company has invested $0.1 million in Langhorne Partners ( 2018 - $0.1 million ), the general partner for Langhorne and the entity which manages the third-party investors investing into Langhorne Holdings. The Company concluded that Langhorne Holdings meets the definition of a VIE as the voting rights are not proportional with the obligations to absorb losses and rights to receive residual returns. The Company evaluated its relationship with Langhorne Holdings and concluded it is not the primary beneficiary of Langhorne Holdings, as it does not have power over the activities that most significantly impact the economic performance of Langhorne Holdings. As a result, the Company does not consolidate the financial position or results of operations of Langhorne Holdings. The Company separately evaluated Langhorne Partners and concluded that it was not a VIE. The Company accounts for its investments in Langhorne Holdings and Langhorne Partners under the equity method of accounting, one quarter in arrears. The Company anticipates that its absolute investment in Langhorne will increase, perhaps materially, as in-force life and annuity blocks of businesses are written. The Company expects its absolute and relative ownership in Langhorne Partners to remain stable. Other than its current and committed future equity investment in Langhorne, the Company has not provided financial or other support to Langhorne that it was not contractually required to provide. Shima Re Shima Re was acquired on March 22, 2019 in connection with the acquisition of TMR. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. Shima Re is a Bermuda domiciled Class 3 insurer. Shima Re is registered as a segregated accounts company and provides third-party investors with access to reinsurance risk formerly managed by TMR. Following the closing of the acquisition, the retrocessionaires providing reinsurance to TMR on certain of the TMR managed third-party capital vehicles’ legacy portfolios of in-force and expired contracts were replaced. The maximum remaining exposure of each segregated account is fully collateralized and is funded by cash and term deposits or investments as prescribed by the participant thereto. Shima Re no longer writes new business and the last in-force contract written by Shima Re expired on December 31, 2019. Shima Re is considered a VIE as it has voting rights that are not proportional to its participating rights. The Company evaluated its relationship with Shima Re and concluded it is not the primary beneficiary of any segregated account, as it does not have power over the activities that most significantly impact the economic performance of any segregated account. As a result, the Company does not consolidate the financial position or results of operations of Shima Re or its segregated accounts. The Company has not provided any financial or other support to any segregated account of Shima Re that it was not contractually required to provide. Norwood Re A subsidiary of RenaissanceRe Europe that the Company acquired in the acquisition of TMR manages Norwood Re. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. Norwood Re is a Bermuda domiciled SPI registered as a segregated accounts company formed to provide solutions for reinsurance-linked asset investors. Norwood Re is wholly owned by the Norwood Re Purpose Trust. Risks assumed by the segregated accounts of Norwood Re are fronted by or ceded from only one cedant - RenaissanceRe Europe and/or its insurance affiliates. The obligations of each segregated account are funded through the issuance of non-voting preference shares to third-party investors. The maximum exposure of each segregated account is fully collateralized and is funded by cash and term deposits or investments as prescribed by the participant thereto. Norwood Re no longer writes new business, and the last in-force contract written by Norwood will expire no later than May 31, 2020. Norwood Re is considered a VIE as it has voting rights that are not proportional to its participating rights. The Company evaluated its relationship with Norwood Re and concluded it is not the primary beneficiary of Norwood Re and its segregated accounts, as it does not have power over the activities that most significantly impact the economic performance of Norwood Re and its segregated accounts. As a result, the Company does not consolidate the financial position or results of operations of Norwood Re and its segregated accounts. The Company has not provided any financial or other support to Norwood Re that it was not contractually required to provide.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Shareholders' Equity	SHAREHOLDERS’ EQUITY Authorized Capital The aggregate authorized capital of RenaissanceRe is 325 million shares consisting of 225 million common shares and 100 million preference shares. The following table is a summary of changes in common shares issued and outstanding: Year ended December 31, 2019 2018 2017 (thousands of shares) Issued and outstanding shares – January 1 42,207 40,024 41,187 Issuance of shares 1,739 1,947 — Repurchase of shares — — (1,322 ) Exercise of options and issuance of restricted stock awards 202 236 159 Issued and outstanding shares – December 31 44,148 42,207 40,024 Dividends The Board of Directors of RenaissanceRe declared dividends of $0.34 per common share, payable to common shareholders of record on March 15, 2019, June 14, 2019 and September 13, 2019 and December 13, 2019 , and the Company paid the dividends on March 29, 2019, June 28, 2019 and September 30, 2019 and December 31, 2019 , respectively. The declaration and payment of dividends on the Company’s common shares are subject to the discretion of the Company’s Board of Directors and depend on the Company’s financial condition, general business conditions, legal, contractual and regulatory restrictions regarding the payment of dividends by the Company and its subsidiaries and other factors which the Board of Directors may consider to be relevant. The Board of Directors approved the payment of quarterly dividends on the Series C 6.08% Preference Shares, Series E 5.375% Preference Shares and 5.750% Series F Preference Shares to preference shareholders of record in the amounts and on the quarterly record dates and dividend payment dates set forth in the prospectus supplement and Certificate of Designation for the applicable series of preference shares, unless and until further action is taken by the Board of Directors. The dividend payment dates for the preference shares will be the first day of March, June, September and December of each year (or if this date is not a business day, on the business day immediately following this date). The record dates for the preference share dividends are one day prior to the dividend payment dates. The amount of the dividend on the Series C 6.08% Preference Shares is an amount per share equal to 6.08% of the liquidation preference per annum (the equivalent to $1.52 per share per annum, or $0.38 per share per quarter). The amount of the dividend on the Series E 5.375% Preference Shares is an amount per share equal to 5.375% of the liquidation preference per annum (the equivalent to $1.34375 per share per annum, or $0.3359375 per share per quarter). The amount of the dividend on the 5.750% Series F Preference Shares is an amount per share equal to 5.750% of the liquidation preference per annum (the equivalent to $1,437.50 per 5.750% Series F Preference Share per annum, or $359.375 per 5.750% Series F Preference Share per quarter, or $1.4375 per Depositary Share per annum, or $0.359375 per Depositary Share per quarter). During 2019 , the Company paid $36.8 million in preference share dividends ( 2018 - $30.1 million , 2017 - $22.4 million ) and $59.4 million in common share dividends ( 2018 - $52.8 million , 2017 - $51.4 million ). Common Shares On March 22, 2019, in connection with the closing of the TMR Stock Purchase, the Company issued 1,739,071 of its common shares to Tokio as part of the aggregate consideration payable to Tokio under the TMR Stock Purchase Agreement. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. On January 9, 2020, Tokio completed a secondary public offering of these common shares, which represented all of Tokio's remaining ownership in the Company. The Company did not receive any proceeds from Tokio’s sale of its common shares. On December 20, 2018, the Company issued 1,947,496 of its common shares to State Farm Mutual Automobile Insurance Company (“State Farm”) in exchange for $250.0 million in a private placement pursuant to an Investment Agreement between the Company and State Farm entered into on October 30, 2018. Preference Shares In March 2004, RenaissanceRe raised $250.0 million through the issuance of 10 million Series C Preference Shares at $25 per share and in May 2013, RenaissanceRe raised $275.0 million through the issuance of 11 million Series E Preference Shares at $25 per share. On June 27, 2013, RenaissanceRe redeemed 5 million Series C Preference Shares for $125.0 million plus accrued and unpaid dividends thereon. Following the redemption, 5 million Series C Preference Shares remain outstanding. In June 2018, RenaissanceRe raised $250.0 million through the issuance of 10,000 Series F Preference Shares at $25,000 share (equivalent to 10,000,000 Depositary Shares, each of which represents a 1/1,000th interest in a Series F Preference Share). The Series E Preference Shares and the remaining Series C Preference Shares may be redeemed at any time at $25 per share plus declared and unpaid dividends at RenaissanceRe’s option. The Series F Preference Shares may be redeemed at $25,000 per share (equivalent to $25 per Depositary Share), plus declared and unpaid dividends, at RenaissanceRe’s option on or after June 30, 2023, provided that no redemption may occur prior to June 30, 2028 unless certain redemption requirements are met. Dividends on the Series C Preference Shares are cumulative from the date of original issuance and are payable quarterly in arrears at 6.08% per annum, when, if, and as declared by the Board of Directors. Dividends on the Series E Preference Shares are payable from the date of original issuance on a non-cumulative basis, only when, as and if declared by the Board of Directors, quarterly in arrears at 5.375% per annum. Dividends on the Series F Preference Shares are payable on a non-cumulative basis, only when, as and if declared by the Board of Directors, quarterly in arrears at 5.750% per annum. Unless certain dividend payments are made on the preference shares, RenaissanceRe will be restricted from paying any dividends on its common shares. As stated above, the Board of Directors approved the payment of quarterly dividends on the Series C Preference Shares, Series E Preference Shares and Series F Preference Shares in the amounts and on the quarterly record dates and dividend payment dates set forth in the prospectus supplement and Certificate of Designation for the applicable series of preference shares, unless and until further action is taken by the Board of Directors. The preference shares have no stated maturity and are not convertible into any other securities of RenaissanceRe. Generally, the preference shares have no voting rights. Whenever dividends payable on the preference shares are in arrears (whether or not such dividends have been earned or declared) in an amount equivalent to dividends for six full dividend periods (whether or not consecutive), the holders of the preference shares, voting as a single class regardless of class or series, will have the right to elect two directors to the Board of Directors of RenaissanceRe. Share Repurchases The Company’s share repurchase program may be effected from time to time, depending on market conditions and other factors, through open market purchases and privately negotiated transactions. On November 10, 2017 , RenaissanceRe’s Board of Directors approved a renewal of its authorized share repurchase program for an aggregate amount of up to $500.0 million . Unless terminated earlier by RenaissanceRe’s Board of Directors, the program will expire when the Company has repurchased the full value of the common shares authorized. The Company’s decision to repurchase common shares will depend on, among other matters, the market price of the common shares and the capital requirements of the Company. During 2019 , the Company did not repurchase any of its common shares under the share repurchase program. At December 31, 2019 , $500.0 million remained available for repurchase under the share repurchase program.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE The following table sets forth the computation of basic and diluted earnings per common share: Year ended December 31, 2019 2018 2017 (common shares in thousands) Numerator: Net income (loss) available (attributable) to RenaissanceRe common shareholders $ 712,042 $ 197,276 $ (244,770 ) Amount allocated to participating common shareholders (1) (8,545 ) (2,121 ) (457 ) Net income (loss) allocated to RenaissanceRe common shareholders $ 703,497 $ 195,155 $ (245,227 ) Denominator: Denominator for basic income (loss) per RenaissanceRe common share - weighted average common shares 43,119 39,732 39,854 Per common share equivalents of employee stock options and performance shares 56 23 — Denominator for diluted income (loss) per RenaissanceRe common share - adjusted weighted average common shares and assumed conversions 43,175 39,755 39,854 Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – basic $ 16.32 $ 4.91 $ (6.15 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – diluted $ 16.29 $ 4.91 $ (6.15 ) (1) Represents earnings attributable to holders of unvested shares issued pursuant to the Company’s stock compensation plans and to the Company’s non-employee directors.

Related Party Transactions and

Related Party Transactions and Major Customers	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions and Major Customers	RELATED PARTY TRANSACTIONS AND MAJOR CUSTOMERS Tower Hill The Company has equity interests in the Tower Hill Companies as described in “Note 5 . Investments.” The Company has entered into reinsurance arrangements with certain subsidiaries and affiliates of Tower Hill and has also entered into reinsurance arrangements with respect to business produced by the Tower Hill Companies. As part of the acquisition of TMR, the Company acquired certain assumed and ceded reinsurance arrangements with certain subsidiaries and affiliates of Tower Hill and other assumed and ceded reinsurance arrangements with respect to business produced by the Tower Hill Companies. The impact of these reinsurance arrangements is included in the Company’s results of operation since the date of acquisition of TMR, March 22, 2019, through December 31, 2019, and on the Company’s consolidated balance sheet at December 31, 2019. During 2019 , the Company recorded $39.8 million ( 2018 - $45.5 million , 2017 - $39.1 million ) of gross premiums written assumed from the Tower Hill Companies and its subsidiaries and affiliates. Gross premiums earned totaled $40.7 million ( 2018 - $43.8 million , 2017 - $35.7 million ) and expenses incurred were $6.1 million ( 2018 - $7.1 million , 2017 - $5.1 million ) for 2019 . The Company had a net related outstanding receivable balance of $14.8 million as of December 31, 2019 ( 2018 - receivable of $19.3 million ). During 2019 , the Company assumed net claims and claim expenses of $37.7 million ( 2018 - assumed net claims and claim expenses of $111.2 million , 2017 - assumed net claims and claim expenses of $94.4 million ) and, as of December 31, 2019 , had a net reserve for claims and claim expenses of $71.8 million ( 2018 - $98.8 million ). During 2019 , the Company recorded $0.5 million of ceded premium written to the Tower Hill Companies and its subsidiaries and affiliates. Ceded premiums earned totaled $0.4 million and expenses ceded were $Nil for 2019 . The Company had a net related outstanding payable balance of $Nil as of December 31, 2019 . During 2019 , the Company recovered net claims and claim expenses of $41.8 million and, as of December 31, 2019 , had a reinsurance recoverable balance of $21.8 million . In addition, the Company received distributions of $13.4 million from the Tower Hill Companies during 2019 ( 2018 - $12.1 million , 2017 - $8.3 million ). Top Layer Re During 2019 , the Company received distributions from Top Layer Re of $20.0 million ( 2018 - $12.5 million , 2017 - $20.0 million ), and recorded a management fee of $2.3 million ( 2018 - $2.7 million , 2017 - $2.7 million ). The management fee reimburses the Company for services it provides to Top Layer Re. Broker Concentration During 2019 , the Company received 79.6% of its gross premiums written ( 2018 - 75.2% , 2017 - 76.4% ) from three brokers. Subsidiaries and affiliates of AON, Marsh, and Willis Towers Watson accounted for 41.7% , 27.1% and 10.8% , respectively, of gross premiums written in 2019 ( 2018 - 40.7% , 24.6% and 9.9% , respectively, 2017 - 42.8% , 23.8% and 9.8% , respectively).

Taxation

Taxation	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Taxation	TAXATION Under current Bermuda law, RenaissanceRe and its Bermuda subsidiaries are not subject to any income or capital gains taxes. In the event that such taxes are imposed, RenaissanceRe and its Bermuda subsidiaries would be exempted from any such tax until March 2035 pursuant to the Bermuda Exempted Undertakings Tax Protection Act 1966, and Amended Acts of 1987 and 2011, respectively. RenaissanceRe Finance and its subsidiaries are subject to income taxes imposed by U.S. federal and state authorities and file a consolidated U.S. federal income tax return. Should the U.S. subsidiaries pay a dividend to RenaissanceRe, withholding taxes would apply to the extent of current year or accumulated earnings and profits at an expected tax rate of 5.0% . The Company also has operations in Ireland, the U.K., Singapore, Switzerland and Australia which are subject to income taxes imposed by the respective jurisdictions in which they operate. Withholding taxes would not be expected to apply to dividends paid to RenaissanceRe from its subsidiaries in Ireland, the U.K., Singapore Switzerland and Australia. The following is a summary of the Company’s income (loss) before taxes allocated between domestic and foreign operations: Year ended December 31, 2019 2018 2017 Domestic Bermuda $ 861,068 $ 349,959 $ (262,827 ) Foreign U.S. 102,724 (56,261 ) (11,897 ) Australia 3,390 — — Switzerland 14,255 166 — Ireland (388 ) 551 617 Singapore (6,334 ) (3,226 ) (12,421 ) U.K. (7,233 ) (28,574 ) (41,656 ) Income (loss) before taxes $ 967,482 $ 262,615 $ (328,184 ) Income tax (expense) benefit is comprised as follows: Year ended December 31, 2019 Current Deferred Total Total income tax expense $ (2,128 ) $ (15,087 ) $ (17,215 ) Year ended December 31, 2018 Total income tax (expense) benefit $ (1,668 ) $ 7,970 $ 6,302 Year ended December 31, 2017 Total income tax expense $ (844 ) $ (25,643 ) $ (26,487 ) The Company’s expected income tax provision computed on pre-tax income at the weighted average tax rate has been calculated as the sum of the pre-tax income in each jurisdiction multiplied by that jurisdiction’s applicable statutory tax rate. Statutory tax rates of 0.0% , 21.0% , 12.5% , 19.0% , 17.0% , 21.2% and 30.0% have been used for Bermuda, the U.S., Ireland, the U.K., Singapore, Switzerland and Australia, respectively. The Company’s effective income tax rate, which it calculates as income tax expense divided by net income before taxes, may fluctuate significantly from period to period depending on the geographic distribution of pre-tax net income (loss) in any given period between different jurisdictions with comparatively higher tax rates and those with comparatively lower tax rates. The geographic distribution of pre-tax net income (loss) can vary significantly between periods due to, but not limited to, the following factors: the business mix of net premiums written and earned; the geographic location, the size and the nature of net claims and claim expenses incurred; the amount and geographic location of operating expenses, net investment income, net realized and unrealized gains (losses) on investments; outstanding debt and related interest expense; and the amount of specific adjustments to determine the income tax basis in each of the Company’s operating jurisdictions. In addition, a significant portion of the Company’s gross and net premiums are currently written and earned in Bermuda, which does not have a corporate income tax, including the majority of the Company’s catastrophe business, which can result in significant volatility to its pre-tax net income (loss) in any given period. A reconciliation of the difference between the provision for income taxes and the expected tax provision at the weighted average tax rate is as follows: Year ended December 31, 2019 2018 2017 Expected income tax (expense) benefit $ (22,874 ) $ 17,697 $ 14,216 Nondeductible expenses (7,059 ) (370 ) (276 ) Change in valuation allowance (5,481 ) (5,255 ) (11,718 ) Withholding tax (665 ) (1,831 ) (216 ) Effect of change in tax rate (262 ) (708 ) (38,083 ) Non-taxable foreign exchange gains (losses) (4 ) 586 2,574 Tax exempt income 400 944 3,794 Transfer pricing 2,503 (2,481 ) (11 ) GAAP to statutory accounting difference 6,553 — — Foreign branch adjustments 7,315 — — U.S. base erosion and anti-abuse tax — (1,271 ) — Other 2,359 (1,009 ) 3,233 Income tax (expense) benefit $ (17,215 ) $ 6,302 $ (26,487 ) As a result of the reduction in the U.S. corporate tax rate from 35% to 21% effective January 1, 2018 pursuant to the Tax Cuts and Jobs Act of 2017, the Company recorded a partial write-down of its U.S. deferred tax asset of $36.7 million in 2017. This adjustment is included in effect of change in tax rate in the table above. The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are presented below: At December 31, 2019 2018 Deferred tax assets Tax loss and credit carryforwards $ 111,835 $ 60,395 Unearned premiums 14,430 10,108 Deferred finance charges 10,160 14,646 Reserve for claims and claim expenses 8,984 17,345 Accrued expenses 7,196 4,292 Deferred underwriting results 4,033 3,514 Premiums receivable 3,412 — Investments — 4,427 160,050 114,727 Deferred tax liabilities Deferred acquisition expenses (16,296 ) (11,801 ) VOBA (12,673 ) — Investments (6,468 ) — Intangible assets (2,891 ) — Amortization and depreciation (2,133 ) (2,992 ) (40,461 ) (14,793 ) Net deferred tax asset before valuation allowance 119,589 99,934 Valuation allowance (75,685 ) (35,271 ) Net deferred tax asset $ 43,904 $ 64,663 The Company’s net deferred tax asset is included in other assets on its consolidated balance sheets. During 2019 , the Company recorded a net increase to the valuation allowance of $40.4 million ( 2018 – increase of $5.3 million , 2017 – increase of $11.2 million ). The Company’s net deferred tax asset primarily relates to net operating loss carryforwards and GAAP versus tax basis accounting differences relating to unearned premiums, deferred finance charges, reserves for claims and claim expenses, accrued expenses, deferred underwriting results, premiums receivable, deferred acquisition expenses, VOBA, investments, intangible assets and amortization and depreciation. The Company’s valuation allowance assessment is based on all available information including projections of future GAAP taxable income from each tax-paying component in each tax jurisdiction. A valuation allowance has been provided against deferred tax assets in the U.S., Ireland, the U.K., Singapore and Switzerland. These deferred tax assets relate primarily to net operating loss carryforwards. The acquired valuation allowance of TMR as of March 22, 2019 was $35.7 million , the majority of which was established in the U.S. In the U.S., the Company has net operating loss carryforwards of $338.6 million . Under applicable law, the U.S. net operating loss carryforwards will begin to expire in 2031 . The Company has net operating loss carryforwards of $115.4 million in the U.K., $25.4 million in Singapore, $186.6 million in Switzerland, and $5.6 million in Ireland. Under applicable law, the U.K., Singapore and Irish net operating losses can be carried forward for an indefinite period, while the net operating losses in Switzerland will begin to expire in 2020. The Company had a net payment for U.S. federal, Irish, U.K., Singapore, Switzerland and Australia income taxes of $9.7 million for the year ended 2019 ( 2018 – net payment of $0.3 million , 2017 – net payment of $0.3 million ). The Company has unrecognized tax benefits of $Nil as of December 31, 2019 ( 2018 – $Nil ). Interest and penalties related to unrecognized tax benefits would be recognized in income tax expense. At December 31, 2019 , interest and penalties accrued on unrecognized tax benefits were $Nil ( 2018 – $Nil ). The following filed income tax returns are open for examination with the applicable tax authorities: tax years 2016 through 2018 with the IRS; 2015 through 2018 with Ireland; 2018 with the U.K.; 2015 through 2018 with Singapore; 2018 with Switzerland; and 2015 through 2018 with Australia. The Company does not expect the resolution of these open years to have a significant impact on its results from operations and financial condition.

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2019
Segment Reporting, Measurement Disclosures [Abstract]
Segment Reporting	SEGMENT REPORTING The Company’s reportable segments are defined as follows: (1) Property, which is comprised of catastrophe and other property reinsurance and insurance written on behalf of the Company’s operating subsidiaries and certain joint ventures managed by the Company’s ventures unit, and (2) Casualty and Specialty, which is comprised of casualty and specialty reinsurance and insurance written on behalf of the Company’s operating subsidiaries and certain joint ventures managed by the Company’s ventures unit. In addition to its reportable segments, the Company has an Other category, which primarily includes its strategic investments, investments unit, corporate expenses, capital servicing costs, noncontrolling interests, certain expenses related to acquisitions and the remnants of its former Bermuda-based insurance operations. The results of operations of TMR are reflected in the Company’s existing reportable segments for the year ended December 31, 2019 from March 22, 2019 . The Company’s Property segment is managed by the Chief Underwriting Officer - Property and the Casualty and Specialty segment is managed by the Chief Underwriting Officer - Casualty and Specialty, each of whom operate under the direction of the Company’s Group Chief Underwriting Officer, who in turn reports to the Company’s President and Chief Executive Officer. The Company does not manage its assets by segment; accordingly, net investment income and total assets are not allocated to the segments. A summary of the significant components of the Company’s revenues and expenses by segment is as follows: Year ended December 31, 2019 Property Casualty and Specialty Other Total Gross premiums written $ 2,430,985 $ 2,376,765 $ — $ 4,807,750 Net premiums written $ 1,654,259 $ 1,727,234 $ — $ 3,381,493 Net premiums earned $ 1,627,494 $ 1,710,909 $ — $ 3,338,403 Net claims and claim expenses incurred 965,424 1,131,637 (40 ) 2,097,021 Acquisition expenses 313,761 448,678 (207 ) 762,232 Operational expenses 139,015 84,546 (828 ) 222,733 Underwriting income (loss) $ 209,294 $ 46,048 $ 1,075 256,417 Net investment income 423,833 423,833 Net foreign exchange losses (2,938 ) (2,938 ) Equity in earnings of other ventures 23,224 23,224 Other income 4,949 4,949 Net realized and unrealized gains on investments 414,483 414,483 Corporate expenses (94,122 ) (94,122 ) Interest expense (58,364 ) (58,364 ) Income before taxes and redeemable noncontrolling interests 967,482 Income tax expense (17,215 ) (17,215 ) Net income attributable to redeemable noncontrolling interests (201,469 ) (201,469 ) Dividends on preference shares (36,756 ) (36,756 ) Net income available to RenaissanceRe common shareholders $ 712,042 Net claims and claim expenses incurred – current accident year $ 968,357 $ 1,155,519 $ — $ 2,123,876 Net claims and claim expenses incurred – prior accident years (2,933 ) (23,882 ) (40 ) (26,855 ) Net claims and claim expenses incurred – total $ 965,424 $ 1,131,637 $ (40 ) $ 2,097,021 Net claims and claim expense ratio – current accident year 59.5 % 67.5 % 63.6 % Net claims and claim expense ratio – prior accident years (0.2 )% (1.4 )% (0.8 )% Net claims and claim expense ratio – calendar year 59.3 % 66.1 % 62.8 % Underwriting expense ratio 27.8 % 31.2 % 29.5 % Combined ratio 87.1 % 97.3 % 92.3 % Year ended December 31, 2018 Property Casualty and Specialty Other Total Gross premiums written $ 1,760,926 $ 1,549,501 $ — $ 3,310,427 Net premiums written $ 1,055,188 $ 1,076,714 $ — $ 2,131,902 Net premiums earned $ 1,050,831 $ 925,298 $ — $ 1,976,129 Net claims and claim expenses incurred 497,895 622,320 (197 ) 1,120,018 Acquisition expenses 177,912 255,079 (2 ) 432,989 Operational expenses 112,954 64,883 430 178,267 Underwriting income (loss) $ 262,070 $ (16,984 ) $ (231 ) 244,855 Net investment income 261,866 261,866 Net foreign exchange losses (12,428 ) (12,428 ) Equity in earnings of other ventures 18,474 18,474 Other income 5,969 5,969 Net realized and unrealized losses on investments (175,069 ) (175,069 ) Corporate expenses (33,983 ) (33,983 ) Interest expense (47,069 ) (47,069 ) Income before taxes and redeemable noncontrolling interests 262,615 Income tax benefit 6,302 6,302 Net income attributable to redeemable noncontrolling interests (41,553 ) (41,553 ) Dividends on preference shares (30,088 ) (30,088 ) Net income available to RenaissanceRe common shareholders $ 197,276 Net claims and claim expenses incurred – current accident year $ 719,185 $ 671,582 $ — $ 1,390,767 Net claims and claim expenses incurred – prior accident years (221,290 ) (49,262 ) (197 ) (270,749 ) Net claims and claim expenses incurred – total $ 497,895 $ 622,320 $ (197 ) $ 1,120,018 Net claims and claim expense ratio – current accident year 68.4 % 72.6 % 70.4 % Net claims and claim expense ratio – prior accident years (21.0 )% (5.3 )% (13.7 )% Net claims and claim expense ratio – calendar year 47.4 % 67.3 % 56.7 % Underwriting expense ratio 27.7 % 34.5 % 30.9 % Combined ratio 75.1 % 101.8 % 87.6 % Year ended December 31, 2017 Property Casualty and Specialty Other Total Gross premiums written $ 1,440,437 $ 1,357,110 $ (7 ) $ 2,797,540 Net premiums written $ 978,014 $ 893,307 $ 4 $ 1,871,325 Net premiums earned $ 931,070 $ 786,501 $ 4 $ 1,717,575 Net claims and claim expenses incurred 1,297,985 565,026 (1,583 ) 1,861,428 Acquisition expenses 113,816 233,077 (1 ) 346,892 Operational expenses 94,194 66,548 36 160,778 Underwriting (loss) income $ (574,925 ) $ (78,150 ) $ 1,552 (651,523 ) Net investment income 222,209 222,209 Net foreign exchange gains 10,628 10,628 Equity in earnings of other ventures 8,030 8,030 Other income 9,415 9,415 Net realized and unrealized gains on investments 135,822 135,822 Corporate expenses (18,572 ) (18,572 ) Interest expense (44,193 ) (44,193 ) Loss before taxes and redeemable noncontrolling interests (328,184 ) Income tax expense (26,487 ) (26,487 ) Net loss attributable to redeemable noncontrolling interests 132,282 132,282 Dividends on preference shares (22,381 ) (22,381 ) Net loss attributable to RenaissanceRe common shareholders $ (244,770 ) Net claims and claim expenses incurred – current accident year $ 1,343,581 $ 558,843 $ — $ 1,902,424 Net claims and claim expenses incurred – prior accident years (45,596 ) 6,183 (1,583 ) (40,996 ) Net claims and claim expenses incurred – total $ 1,297,985 $ 565,026 $ (1,583 ) $ 1,861,428 Net claims and claim expense ratio – current accident year 144.3 % 71.1 % 110.8 % Net claims and claim expense ratio – prior accident years (4.9 )% 0.7 % (2.4 )% Net claims and claim expense ratio – calendar year 139.4 % 71.8 % 108.4 % Underwriting expense ratio 22.3 % 38.1 % 29.5 % Combined ratio 161.7 % 109.9 % 137.9 % The following is a summary of the Company’s gross premiums written allocated to the territory of coverage exposure: Year ended December 31, 2019 2018 2017 Property U.S. and Caribbean $ 1,368,205 $ 978,063 $ 954,269 Worldwide 643,744 464,311 305,915 Europe 182,544 144,857 49,486 Japan 90,328 71,601 49,821 Worldwide (excluding U.S.) (1) 79,393 66,872 48,182 Australia and New Zealand 32,203 19,273 14,151 Other 34,568 15,949 18,613 Total Property 2,430,985 1,760,926 1,440,437 Casualty and Specialty Worldwide 935,626 776,976 686,253 U.S. and Caribbean 1,071,170 667,125 622,757 Worldwide (excluding U.S.) (1) 25,291 31,734 10,104 Europe 227,178 15,296 9,752 Australia and New Zealand 34,053 3,667 4,141 Other 83,447 54,703 24,103 Total Casualty and Specialty 2,376,765 1,549,501 1,357,110 Other category — — (7 ) Total gross premiums written $ 4,807,750 $ 3,310,427 $ 2,797,540 (1) The category “Worldwide (excluding U.S.)” consists of contracts that cover more than one geographic region (other than the U.S.).

Stock Incentive Compensation an

Stock Incentive Compensation and Employee Benefit Plans	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Stock Incentive Compensation and Employee Benefit Plans	STOCK INCENTIVE COMPENSATION AND EMPLOYEE BENEFIT PLANS Stock Incentive Compensation Plans and Awards The Company is authorized to issue restricted stock awards, restricted stock units, performance share awards, stock options and other share-based awards to its employees and directors pursuant to various stock incentive compensation plans. On May 16, 2016, the Company’s shareholders approved the Company’s 2016 Long-Term Incentive Plan (the “2016 Long-Term Incentive Plan”). Pursuant to the 2016 Long-Term Incentive Plan, the Company is authorized to issue up to 1,625,000 common shares plus the number of shares that were subject to awards outstanding under the Company’s 2001 Stock Incentive Plan, as amended (the “2001 Stock Incentive Plan”) and the Company’s 2010 Performance-Based Equity Incentive Plan, as amended (the “2010 Performance Plan”) as of the effective date of the 2016 Long-Term Incentive Plan that are forfeited, canceled, settled in cash, or otherwise terminated without delivery after the effective date. The 2016 Long-Term Incentive Plan permits the grant of restricted stock awards, restricted stock units, performance share awards (including cash-based performance awards), stock options and other share-based awards to employees, officers, non-employee directors and consultants or advisors of the Company and its affiliates. The 2001 Stock Incentive Plan, which permitted the grant of stock options, restricted stock awards and other share-based awards to employees of RenaissanceRe and its subsidiaries, expired in accordance with its terms on February 6, 2016 and no additional awards may be made under this plan. All outstanding awards made under the 2001 Stock Incentive Plan will vest no later than March 1, 2020. The 2010 Performance Plan, pursuant to which the Company granted performance share awards, was terminated on May 16, 2016 upon approval of the 2016 Long-Term Incentive Plan, and no additional awards will be made under this plan. All outstanding awards made under the 2010 Performance Share Plan vested no later than February 7, 2018. The terms and conditions of outstanding awards granted under the 2001 Share Incentive Plan and the 2010 Performance Plan were not affected by the respective expiration and termination of these plans. In 2010, the Company instituted a cash settled restricted stock unit (“CSRSU”) plan, the 2010 Restricted Stock Unit Plan, which allowed for the issuance of equity awards in the form of CSRSUs. In November 2016, the 2010 Restricted Stock Plan was terminated and replaced with a new cash settled restricted stock unit plan, the 2016 Restricted Stock Unit Plan. The terms and conditions of CSRSU awards outstanding under the 2010 Restricted Stock Unit Plan at the time of termination were not affected, but no additional awards will be made under the 2010 Restricted Stock Unit Plan. All outstanding awards made under the 2010 Restricted Stock Unit Plan will vest no later than March 1, 2020. Stock Options The Company has not granted stock options since 2008. Stock options were granted pursuant to the 2001 Stock Incentive Plan and allowed for the purchase of RenaissanceRe common shares at a price that was equal to, or not less than, the fair market value of RenaissanceRe common shares as of the effective grant date. Stock options generally vested over 4 years and expired 10 years from the grant date. The final stock options outstanding were exercised during the year ended December 31, 2018. Restricted Stock Awards Restricted stock awards granted periodically under the 2001 Stock Incentive Plan and the 2016 Long-Term Incentive Plan generally vest ratably over a four year period. The Company has also granted restricted stock awards to non-employee directors, which generally vest ratably over a three year period. Performance Share Awards Performance share awards have been granted periodically to certain of the Company’s executive officers pursuant to the 2010 Performance Plan, 2001 Share Incentive Plan and 2016 Long-Term Incentive Plan. Outstanding performance share awards are subject to vesting conditions based on both continued service and the attainment of pre-established performance goals. If performance goals are achieved, the performance share awards will vest up to a maximum of 250% of target. Performance share awards generally cliff vest at the end of a three -year vesting period based on the attainment of annual performance goals over the vesting period. The performance share awards granted prior to May 2018 have a market condition, which is the Company’s total shareholder return relative to its peer group. The performance share awards granted in May 2018 and March 2019 have a performance condition, which is the percentage change in the Company’s tangible book value per common share plus accumulated dividends, or, in the event of a change in control, a market condition, which is the Company’s total shareholder return relative to its peer group. Total shareholder return is calculated in accordance with the terms of the applicable award agreement and is generally based on the average closing share price over the 20 trading days preceding and including the start and end of the annual performance period. The percentage change in tangible book value per share plus accumulated dividends is calculated in accordance with the terms of the applicable award agreement. Cash Settled Restricted Stock Units CSRSUs are liability awards with fair value measurement based on the fair market value of the Company’s common shares at the end of each reporting period. CSRSUs granted periodically pursuant to the 2010 Restricted Stock Unit Plan and 2016 Restricted Stock Unit Plan generally vest ratably over 4 years . Valuation Assumptions Performance Share Awards Granted Prior to May 2018 The fair value of performance share awards granted prior to May 2018 is measured on the grant date using a Monte Carlo simulation model which requires the following inputs: share price; expected volatility; expected term; expected dividend yield; and risk-free interest rates. The following are the weighted average-assumptions used to estimate the fair value for all performance share awards issued in each respective year. Performance Share Awards Year ended December 31, 2019 2018 Expected volatility (1) n/a 15.8% Expected term (in years) n/a n/a Expected dividend yield n/a n/a Risk-free interest rate (1) n/a 1.85% - 2.36% (1) The expected volatility and risk-free interest rate applied are specific to each tranche of performance share awards. Expected volatility: The expected volatility is estimated by the Company based on RenaissanceRe’s historical stock volatility. Expected term: The expected term is not applicable as the length of the performance periods are fixed and not subject to future employee behavior. Each tranche of the performance share awards has a one year period during which performance is measured. Expected dividend yield: The expected dividend yield is not applicable to performance share awards as dividends are paid at the end of the vesting period and do not affect the value of the performance shares. Risk-free interest rate: The risk free rate is estimated based on the yield on a U.S. treasury zero-coupon issued with a remaining term equal to the vesting period of the performance share awards. For performance share awards granted before May 2018, the total cost of the performance share awards is determined on the grant date based on the fair value calculated by the Monte Carlo simulation model. The Company recognizes cost equal to fair value per performance share award multiplied by the target number of performance share awards on the grant date. The cost is then amortized as an expense over the requisite service period. The Company has elected to recognize forfeitures as they occurred rather than estimating service-based forfeitures over the requisite service period. Performance Share Awards Granted in May 2018 and March 2019 For performance share awards granted in May 2018 and March 2019, the performance metric relates to the percentage change in tangible book value per share plus accumulated dividends which is classified as a performance condition under FASB ASC Topic Compensation - Stock Compensation . As a result, the fair value of the performance share awards is determined based on the fair market value of RenaissanceRe’s common shares on the grant date. The estimated fair value of performance share awards is amortized as an expense over the requisite service period. Restricted Stock Awards The fair value of restricted stock awards is determined based on the fair market value of RenaissanceRe’s common shares on the grant date. The estimated fair value of restricted stock awards is amortized as an expense over the requisite service period. The Company has elected to recognize forfeitures as they occurred rather than estimating service-based forfeitures over the requisite service period. Cash Settled Restricted Stock Units CSRSUs are revalued at the end of each quarterly reporting period based on the then fair market value of RenaissanceRe’s common shares. The total cost is adjusted each quarter for unvested CSRSUs to reflect the current share price, and this total cost is amortized as an expense over the requisite service period. The Company has elected to recognize forfeitures as they occurred rather than estimating service-based forfeitures over the requisite service period. Summary of Stock Compensation Activity The following is a summary of activity under the Company’s stock compensation plans. Stock Options Weighted options outstanding Weighted average exercise price Weighted average remaining contractual life Aggregate intrinsic value Range of exercise prices Balance, December 31, 2016 206,795 $ 53.17 0.9 $ 17,174 $50.71 - $59.66 Options granted — — — Options forfeited — — Options expired — — Options exercised (174,794 ) 53.04 $ 15,945 $50.71 - $59.66 Balance, December 31, 2017 32,001 $ 53.86 0.2 $ 2,295 $ 53.86 Options granted — — — Options forfeited — — Options expired — — Options exercised (32,001 ) 53.86 $ 2,320 $ 53.86 Balance, December 31, 2018 — $ — 0.0 $ — $ — Cash Settled Restricted Stock Units Number of shares Nonvested at December 31, 2016 308,344 Awards granted 98,067 Awards vested (122,088 ) Awards forfeited (21,993 ) Nonvested at December 31, 2017 262,330 Awards granted — Awards vested (108,344 ) Awards forfeited (7,069 ) Nonvested at December 31, 2018 146,917 Awards granted — Awards vested (80,012 ) Awards forfeited (3,161 ) Nonvested at December 31, 2019 63,744 Performance Share Awards Number of shares (1) Weighted average grant-date fair value Nonvested at December 31, 2016 211,381 $ 44.63 Awards granted 64,947 $ 65.27 Awards vested (62,499 ) $ 43.51 Awards forfeited (46,156 ) Nonvested at December 31, 2017 167,673 $ 53.11 Awards granted 83,475 $ 60.69 Awards vested (16,456 ) $ 53.79 Awards forfeited (82,241 ) Nonvested at December 31, 2018 152,451 $ 57.21 Awards granted 58,050 $ 146.10 Awards vested (21,730 ) $ 49.90 Awards forfeited (43,924 ) Nonvested at December 31, 2019 144,847 $ 94.70 (1) For performance share awards, the number of shares is stated at the maximum number that can be attained if the performance conditions are fully met. Forfeitures represent shares forfeited due to vesting below the maximum attainable as a result of the Company not fully meeting the performance conditions. Restricted Stock Awards Employee restricted stock awards Non-employee director restricted stock awards Total restricted stock awards Number of shares Weighted average grant date fair value Number of shares Weighted Number of shares Weighted Nonvested at December 31, 2016 402,170 $ 103.34 25,545 $ 107.95 427,715 $ 103.61 Awards granted 116,345 148.66 12,193 150.05 128,538 148.79 Awards vested (185,478 ) 100.17 (17,612 ) 110.66 (203,090 ) 101.08 Awards forfeited — — — — — — Nonvested at December 31, 2017 333,037 $ 120.93 20,126 $ 131.09 353,163 $ 121.51 Awards granted 255,799 132.70 12,169 127.29 267,968 132.79 Awards vested (139,454 ) 112.70 (9,761 ) 123.59 (149,215 ) 113.41 Awards forfeited (1,642 ) 134.38 — — (1,642 ) 134.38 Nonvested at December 31, 2018 447,740 $ 130.37 22,534 $ 132.29 470,274 $ 130.46 Awards granted 242,832 146.92 11,444 147.43 254,276 146.94 Awards vested (165,245 ) 124.71 (12,972 ) 131.88 (178,217 ) 125.23 Awards forfeited (14,467 ) 136.16 — — (14,467 ) 136.16 Nonvested at December 31, 2019 510,860 $ 139.91 21,006 $ 140.79 531,866 $ 139.94 There were 1.3 million shares available for issuance under the 2016 Long-Term Incentive Plan at December 31, 2019 and no shares available for issuance under the 2001 Stock Incentive Plan or 2010 Performance Share Plan at December 31, 2019 . The aggregate fair value of restricted stock awards, performance share awards and CSRSUs vested during 2019 was $41.6 million ( 2018 – $37.2 million , 2017 – $56.9 million ). Cash in the amount of $Nil was received from employees as a result of employee stock option exercises during 2019 ( 2018 – $Nil , 2017 – $Nil ). In connection with share vestings and option exercises, there was a $0.2 million excess windfall tax benefit realized by the Company in 2019 ( 2018 – $Nil , 2017 – $Nil ). RenaissanceRe issues new shares upon the exercise of an option. The total stock compensation expense recognized in the Company’s consolidated statements of operations during 2019 was $41.4 million ( 2018 – $35.7 million , 2017 – $37.2 million ). As of December 31, 2019 , there was $52.6 million of total unrecognized compensation cost related to restricted stock awards, $5.4 million related to CSRSUs and $7.7 million related to performance share awards, which will be recognized, on a weighted average basis, during the next 1.7 , 0.9 and 1.4 years, respectively. All of the Company’s employees are eligible for defined contribution pension plans. Contributions are primarily based upon a percentage of eligible compensation. The Company contributed $4.9 million to its defined contribution pension plans in 2019 ( 2018 – $4.1 million , 2017 – $4.4 million ).

Statutory Requirements

Statutory Requirements	12 Months Ended
	Dec. 31, 2019
Insurance [Abstract]
Statutory Requirements	STATUTORY REQUIREMENTS The Company’s (re)insurance operations are subject to insurance laws and regulations in the jurisdictions in which they operate, the most significant of which currently include Bermuda, Switzerland, the U.K. and the U.S. These regulations include certain restrictions on the amount of dividends or other distributions, such as loans or cash advances, available to shareholders without prior approval of the respective regulatory authorities. Group Supervision The Bermuda Monetary Authority (“BMA”) is the group supervisor of the Company. Under the Insurance Act 1978, amendments thereto and related regulations of Bermuda (collectively, the “Insurance Act”), the Company shall ensure that it can meet its minimum solvency margin (“MSM”), defined as the prescribed minimum amount by which the value of the assets of the Company must exceed the value of its liabilities, the breach of which represents an unacceptable level of risk and triggers the strongest supervisory actions. In addition, the Company is required to maintain statutory economic capital and surplus at a level equal to or in excess of its enhanced capital requirement (“ECR”) which is established by reference to the Bermuda Solvency Capital Requirement (the “BSCR”) model. The BSCR is a mathematical model designed to give the BMA robust methods for determining an insurer’s capital adequacy. The ECR is equal to the greater of the MSM or required capital calculated by reference to the BSCR. Effective January 1, 2016, the BMA embedded the Economic Balance Sheet (“EBS”) framework in the Bermuda legislative and regulatory regime. The EBS is an input to the BSCR which determines the Company’s ECR. The EBS regime prescribes the use of financial statements prepared in accordance with GAAP as the basis on which statutory financial statements are prepared, and those statutory financial statements form the starting basis for the EBS. The BMA has established a target capital level (“TCL”) which is set at 120% of the ECR. While the Company is not required to maintain statutory economic capital and surplus at this level, it serves as an early warning signal for the BMA, and failure to meet the TCL may result in additional reporting requirements or increased regulatory oversight. The Company is currently completing its 2019 group BSCR, which must be filed with the BMA on or before May 31, 2020 , and at this time, the Company believes it will exceed the target level of required statutory economic capital and surplus. The statutory capital and surplus, required minimum statutory capital and surplus and unrestricted net assets of the Company’s regulated insurance operations in its most significant regulatory jurisdictions are detailed below: Bermuda (1) Switzerland (2) U.K. (3) (4) U.S. At December 31, 2019 2018 2019 2018 2019 2018 2019 2018 Statutory capital and surplus $ 5,325,749 $ 4,366,089 $ 580,235 $ — $ 675,864 $ 519,689 $ 677,832 $ 502,803 Required statutory capital and surplus 1,201,529 957,650 465,900 — 675,864 519,689 397,447 306,628 Unrestricted net assets 1,107,586 931,387 102,943 — — — 46,630 31,228 (1) The Company's Bermuda-domiciled insurance subsidiaries’ capital and surplus is based on the relevant insurer’s statutory financial statements and required statutory capital and surplus is based on the MSM. (2) RenaissanceRe Europe’s statutory capital and surplus and required statutory capital and surplus incorporate a full year of statutory net loss and risk capital, respectively. (3) With respect to statutory capital and surplus and required statutory capital and surplus, and as described below, underwriting capacity of a member of Lloyd’s must be supported by providing a deposit in the form of cash, securities or letters of credit, which are referred to as Funds at Lloyd’s (“FAL”). FAL is determined by Lloyd’s and is based on Syndicate 1458’s solvency and capital requirements as calculated through its internal model. (4) Syndicate 1458 is capitalized by its FAL, with the related assets not held on its balance sheet. As such, unrestricted net assets is not applicable to Syndicate 1458; however, the Company can make an application to obtain approval from Lloyd’s to have funds released to RenaissanceRe from Syndicate 1458, subject to passing a Lloyd’s release test. Statutory net income (loss) of the Company’s regulated insurance operations in its most significant regulatory jurisdictions are detailed below: Statutory Net Income (Loss) Bermuda Switzerland U.K. U.S. Year ended December 31, 2019 $ 657,182 $ (14,679 ) $ (666,595 ) $ 37,827 Year ended December 31, 2018 326,386 — (6,692 ) 25,851 Year ended December 31, 2017 (334,142 ) — (57,050 ) (3,627 ) The difference between statutory financial statements and statements prepared in accordance with GAAP varies by jurisdiction; however, the primary difference is that for the Company’s regulated entities the statutory financial statements generally do not reflect goodwill and intangible assets. Also, in the U.S., fixed maturity investments are generally recorded at amortized cost and deferred income tax is charged directly to equity. In the U.S. deferred acquisition costs are generally not reflected in the statutory financial statements. In Switzerland, currency translation adjustment losses are directly charged to net income or loss, while translation gains are not admissible and reflected as translation reserve on the statutory balance sheet. In addition, fixed maturity investments are carried at the lower of amortized cost and market value and recognition of equalization reserves is allowed. The prudence principle standard also allows for valuating certain assets below their nominal value. None of the Company’s insurance subsidiaries used permitted practices that prevented the trigger of a regulatory event during the years ended December 31, 2019 , 2018 and 2017 . Dividend Restrictions of RenaissanceRe As a Bermuda-domiciled holding company, RenaissanceRe has limited operations of its own and its assets consist primarily of investments in subsidiaries, and to a degree, cash and securities. Accordingly, RenaissanceRe’s future cash flows largely depend on the availability of dividends or other statutorily permissible payments from subsidiaries. The ability to pay such dividends is limited by the applicable laws and regulations of the various countries and states in which these subsidiaries operate, including, among others, Bermuda, Switzerland, the U.S., the U.K. and Ireland. RenaissanceRe’s ability to pay dividends and distribute capital to shareholders is limited by the Bermuda Companies Act 1981, insofar as both before and after the payment, RenaissanceRe must still be able to pay its liabilities as they come due and the realizable value of its assets must be greater than its liabilities. Bermuda-Domiciled Insurance Entities Under the Insurance Act, certain subsidiaries of RenaissanceRe are required to prepare and file statutory financial statements. The BMA prescribed the use of financial statements prepared in accordance with GAAP as the basis on which the statutory financial statements are prepared, subject to the application of certain prudential filters. These statutory financial statements are used to prepare the EBS. In addition, Bermuda insurance subsidiaries of RenaissanceRe are required to maintain certain measures of solvency and liquidity and file a BSCR return. Class 3B and Class 4 Insurers Under the Insurance Act, RenaissanceRe Specialty U.S. and Vermeer are defined as Class 3B insurers, and Renaissance Reinsurance and DaVinci are classified as Class 4 insurers, and therefore must maintain statutory economic capital and surplus at a level at least equal to its ECR which is the greater of its MSM and the required capital calculated by reference to the BSCR. Class 3B and Class 4 insurers are prohibited from declaring or paying any dividends if in breach of the required minimum solvency margin or minimum liquidity ratio (the “Relevant Margins”) or if the declaration or payment of such dividend would cause the insurer to fail to meet the Relevant Margins. Where an insurer fails to meet its Relevant Margins on the last day of any financial year, it is prohibited from declaring or paying any dividends during the next financial year without the prior approval of the BMA. Further, Class 3B and Class 4 insurers are prohibited from declaring or paying in any financial year dividends of more than 25% of its total statutory capital and surplus (as shown on its previous financial year’s statutory balance sheet) unless it files (at least seven days before payment of such dividends) with the BMA an affidavit stating that it will continue to meet its Relevant Margins. Class 3B and Class 4 insurers must obtain the BMA’s prior approval for a reduction by 15% or more of the total statutory capital as set forth in its previous year’s financial statements. These restrictions on declaring or paying dividends and distributions under the Insurance Act are in addition to the solvency requirements under the Bermuda Companies Act 1981 which apply to all Bermuda companies. In addition, an insurer engaged in general business is also required to maintain the value of its relevant assets at not less than 75% of the amount of its relevant liabilities. The Company is currently completing its 2019 Bermuda-domiciled statutory filings for Renaissance Reinsurance, DaVinci, RenaissanceRe Specialty U.S. and Vermeer, which must be filed with the BMA on or before April 30, 2020 , and at this time, the Company believes each of Renaissance Reinsurance, DaVinci, RenaissanceRe Specialty U.S. and Vermeer will exceed the target level of required statutory economic capital. SPIs Under the Insurance Act, Upsilon RFO is considered an SPI. Refer to “Note 11 . Variable Interest Entities” for additional information related to Upsilon RFO. Unlike other (re)insurers, such as the Class 3B and Class 4 insurers discussed above, SPIs are fully funded to meet their (re)insurance obligations and are not exposed to insolvency, therefore the application and supervision processes are streamlined to facilitate the transparent structure. Further, the BMA has the discretion to modify such insurer’s reporting requirements under the Insurance Act. Like other (re)insurers, the principal representative of an SPI has a duty to inform the BMA in relation to solvency matters, where applicable. Upsilon RFO applied for and received a direction from the BMA, which, subject to specified conditions, modified its filing requirements in respect of statutory financial statements for the years ended December 31, 2019 and 2018 . Switzerland Domiciled Insurance Entity RenaissanceRe Europe is regulated by the Swiss Financial Market Supervisory Authority (“FINMA”) pursuant to the Insurance Supervision Act. Its accounts are prepared in accordance with the Swiss Code of Obligations, the Insurance Supervision Act and the Insurance Supervision Ordinance. RenaissanceRe Europe is obligated to maintain a minimum level of capital based on the Swiss Code of Obligations and Insurance Supervision Act. In addition, it is required to perform a minimum solvency margin calculation based on the Swiss Solvency Test (“SST”) regulations as stipulated by the Insurance Supervision Act and the Insurance Supervision Ordinance. The SST is based on an economic view and required capital is derived from a combination of internal and standard models. While the minimum required capital under both the Swiss Code of Obligations and the Insurance Supervision Act might be met, the actual minimum threshold is the target capital as determined from the SST. The dividend amount that RenaissanceRe Europe is permitted to distribute is restricted to freely distributable reserves which consist of retained earnings and the current year profit. The solvency and capital requirements must still be met following any distribution. RenaissanceRe Europe is currently completing its 2019 statutory basis financial statements, which we expect to file with FINMA on or before April 30, 2020 . At December 31, 2019 , the Company believes that RenaissanceRe Europe will exceed the minimum solvency and capital requirements required to be maintained under Swiss law. RenaissanceRe Europe has branches in Australia, Bermuda, the U.K. and the U.S. RenaissanceRe Europe AG, Australia Branch is regulated by the Australian Prudential Regulation Authority (“APRA”) and is authorized to carry on insurance business under subsection 12(2) of the Insurance Act 1973. RenaissanceRe Europe’s Australia branch’s regulatory reporting is prepared in accordance with the Australian Accounting Standards and APRA Prudential Standards. APRA Prudential Standards require the maintenance of net assets in Australia in excess of a calculated Prescribed Capital Amount (“PCA”). At December 31, 2019 , the Company believes the net assets in Australia of RenaissanceRe Europe’s Australia branch were above the PCA estimated under the APRA Prudential Standards. RenaissanceRe Europe AG, Bermuda Branch is registered as a Class 3B insurer under the Insurance Act. For the year ended December 31, 2019 , it was granted exemptions and modifications to the requirements to file an annual statutory financial return, maintain minimum levels of statutory capital and surplus and file a capital and solvency return. These are the same exemptions and modifications granted for the year ended December 31, 2018 . RenaissanceRe Europe AG, UK Branch is authorized by the Prudential Regulation Authority (the “PRA”), and is regulated by both the PRA and Financial Conduct Authority (the “FCA”). It is subject to the Solvency II regime and applied for and was granted a modification of the rules for the year ended December 31, 2019. RenaissanceRe Europe AG, US Branch (“RenaissanceRe Europe, US Branch”) is required to file statutory basis financial statements prepared in accordance with statutory accounting practices prescribed or permitted by the U.S. insurance regulators. RenaissanceRe Europe, US Branch, whose port of entry is New York, is subject to statutory accounting principles as defined by the National Association of Insurance Commissions (“NAIC”). The NAIC uses a risk-based capital (“RBC”) model to monitor and regulate the solvency of licensed life, health, and property and casualty insurance and reinsurance companies. The state of New York has adopted the NAIC’s model law. Laws and regulations in the U.S. establish minimum capital adequacy levels and grant regulators the authority to take specific actions based on the level of impairment. The RenaissanceRe Europe, US Branch’s minimum required statutory capital and surplus is based on Company Action Level (“CAL”) RBC or minimum requirements per state insurance regulation. The Company is currently completing the 2019 statutory basis financial statements for the RenaissanceRe Europe, US Branch, which must be filed with the state of New York, the NAIC and other state insurance regulators on or before March 1, 2020. At this time, the Company believes that the RenaissanceRe Europe, US Branch will exceed the minimum required statutory capital and surplus. U.K.-Domiciled Syndicate 1458 RenaissanceRe CCL and Syndicate 1458 are subject to oversight by the Council of Lloyd’s. RSML is authorized by the U.K.’s Prudential Regulation Authority and regulated by the Financial Conduct Authority under the Financial Services and Markets Act 2000. Underwriting capacity of a member of Lloyd’s must be supported by providing a deposit in the form of cash, securities or letters of credit, which are referred to as FAL. This amount is determined by Lloyd’s and is based on Syndicate 1458’s solvency and capital requirement as calculated through its internal model. In addition, if the FAL are not sufficient to cover all losses, the Lloyd’s Central Fund provides an additional discretionary level of security for policyholders. U.S.-Domiciled Insurance Entities Renaissance Reinsurance U.S. is subject to statutory accounting principles as defined by the NAIC. As noted above, the NAIC uses a RBC model to monitor and regulate the solvency of licensed life, health, and property and casualty insurance and reinsurance companies. Renaissance Reinsurance U.S. is domiciled in Maryland, which has adopted the NAIC's model law. Laws and regulations in the U.S. establish minimum capital adequacy levels and grant regulators the authority to take specific actions based on the level of impairment. Based on Maryland’s adoption of the RBC model of the NAIC, the first level at which action is required is CAL RBC. If Renaissance Reinsurance U.S.’s total adjusted capital is less than CAL RBC (but greater than Regulatory Action Level (“RAL”) RBC), then Renaissance Reinsurance U.S. must file an RBC plan with the Maryland Insurance Commissioner (the "Commissioner"). If Renaissance Reinsurance U.S.’s total adjusted capital is less than RAL RBC, then the Commissioner must take certain regulatory actions. Under Maryland insurance law, Renaissance Reinsurance U.S. must notify the Commissioner within five business days after the declaration of any dividend or distribution, other than an extraordinary dividend or extraordinary distribution, and notify the Commissioner at least ten days prior to the payment or distribution thereof. The Commissioner has the right to prevent payment of such a dividend or such a distribution if the Commissioner determines, in the Commissioner's discretion, that after the payment thereof, the policyholders' surplus of Renaissance Reinsurance U.S. would be inadequate or could cause Renaissance Reinsurance U.S. to be in a hazardous financial condition. Renaissance Reinsurance U.S. must give at least 30 days prior notice to the Commissioner before paying an extraordinary dividend or making an extraordinary distribution. Extraordinary dividends and extraordinary distributions are dividends or distributions which, together with any other dividends and distributions paid during the immediately preceding twelve-month period, would exceed the lesser of: • 10% of the insurer's statutory policyholders' surplus (as determined under statutory accounting principles) as of December 31 of the prior year; or • the insurer's net investment income excluding realized capital gains (as determined under statutory accounting principles) for the twelve-month period ending on December 31 of the prior year and pro rata distributions of any class of the insurer's securities, plus any amounts of net investment income (subject to the foregoing exclusions) in the three calendar years prior to the preceding year which have not been paid out as dividends. At December 31, 2019 , Renaissance Reinsurance U.S. had an ordinary dividend capacity of $46.6 million which can be paid in 2020 . Renaissance Reinsurance U.S. is required to file statutory basis financial statements with the Maryland Insurance Administration (“MIA”), as its domestic regulator, with the NAIC and with insurance regulators in certain other states where it is licensed, authorized or accredited to do business. The operations of Renaissance Reinsurance U.S. are subject to examination by those state insurance regulators at any time. The Company is currently completing the 2019 statutory basis financial statements for Renaissance Reinsurance U.S., which must be filed with the MIA, the NAIC, and other state insurance regulators on or before March 1, 2020 . At this time, the Company believes Renaissance Reinsurance U.S. will exceed the minimum required statutory capital and surplus. Multi-Beneficiary Reinsurance Trusts Each of Renaissance Reinsurance and DaVinci was approved as a Trusteed Reinsurer in the state of New York and established a multi-beneficiary reinsurance trust (“MBRT”) to collateralize its (re)insurance liabilities associated with U.S. domiciled cedants. The MBRTs are subject to the rules and regulations of the state of New York and the respective deed of trust, including but not limited to certain minimum capital funding requirements, investment guidelines, capital distribution restrictions and regulatory reporting requirements. Assets held under trust at December 31, 2019 with respect to the MBRTs totaled $1.3 billion and $336.5 million for Renaissance Reinsurance and DaVinci, respectively ( 2018 – $1.2 billion and $385.8 million , respectively), compared to the minimum amount required under U.S. state regulations of $927.4 million and $249.4 million , respectively ( 2018 – $1.1 billion and $356.9 million , respectively). Multi-Beneficiary Reduced Collateral Reinsurance Trusts Each of Renaissance Reinsurance, RenaissanceRe Europe and DaVinci has been approved as a “certified reinsurer” eligible for collateral reduction in certain states, and are authorized to provide reduced collateral equal to 20% , 20% and 50% , respectively, of their net outstanding insurance liabilities to insurers domiciled in each of those states. Each of Renaissance Reinsurance and DaVinci has established a multi-beneficiary reduced collateral reinsurance trust (“RCT”) to collateralize its (re)insurance liabilities associated with cedants domiciled in those states. Because the RCTs were established in New York, they are subject to the rules and regulations of the state of New York including but not limited to certain minimum capital funding requirements, investment guidelines, capital distribution restrictions and regulatory reporting requirements. Assets held under trust at December 31, 2019 with respect to the RCTs totaled $51.7 million and $43.8 million for Renaissance Reinsurance and DaVinci, respectively ( 2018 - $50.3 million and $63.2 million , respectively), compared to the minimum amount required under U.S. state regulations of $40.3 million and $40.9 million , respectively ( 2018 - $36.8 million and $26.9 million , respectively).

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2019
Summary of Derivative Instruments [Abstract]
Derivative Instruments	DERIVATIVE INSTRUMENTS From time to time, the Company may enter into derivative instruments such as futures, options, swaps, forward contracts and other derivative contracts primarily to manage its foreign currency exposure, obtain exposure to a particular financial market, for yield enhancement, or for trading and to assume risk. The Company’s derivative instruments can be exchange traded or over-the-counter, with over-the-counter derivatives generally traded under International Swaps and Derivatives Association master agreements, which establish the terms of the transactions entered into with the Company’s derivative counterparties. In the event a party becomes insolvent or otherwise defaults on its obligations, a master agreement generally permits the non-defaulting party to accelerate and terminate all outstanding transactions and net the transactions’ marked-to-market values so that a single sum in a single currency will be owed by, or owed to, the non-defaulting party. Effectively, this contractual close-out netting reduces credit exposure from gross to net exposure. Where the Company has entered into master netting agreements with counterparties, or the Company has the legal and contractual right to offset positions, the derivative positions are generally netted by counterparty and are reported accordingly in other assets and other liabilities. Commencing in 2019, the Company elected to adopt hedge accounting for certain of its derivative instruments used as hedges of a net investment in a foreign operation. The tables below show the gross and net amounts of recognized derivative assets and liabilities at fair value, including the location on the consolidated balance sheets of the Company’s principal derivative instruments: Derivative Assets At December 31, 2019 Gross Amounts of Recognized Assets Gross Amounts Offset in the Balance Sheet Net Amounts of Assets Presented in the Balance Sheet Balance Sheet Location Collateral Net Amount Derivative instruments not designated as hedges Interest rate futures $ 234 $ 122 $ 112 Other assets $ — $ 112 Foreign currency forward contracts (1) 22,702 2,418 20,284 Other assets — 20,284 Foreign currency forward contracts (2) 1,082 622 460 Other assets — 460 Credit default swaps 37 — 37 Other assets — 37 Total return swaps 3,744 — 3,744 Other assets 3,601 143 Equity futures 291 — 291 Other assets — 291 Total derivative instruments not designated as hedges 28,090 3,162 24,928 3,601 21,327 Derivative instruments designated as hedges Foreign currency forward contracts (3) 64 667 (603 ) Other assets — (603 ) Total derivative instruments designated as hedges 64 667 (603 ) — (603 ) Total $ 28,154 $ 3,829 $ 24,325 $ 3,601 $ 20,724 Derivative Liabilities At December 31, 2019 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Balance Sheet Net Amounts of Liabilities Presented in the Balance Sheet Balance Sheet Location Collateral Pledged Net Amount Derivative instruments not designated as hedges Interest rate futures $ 1,545 $ 122 $ 1,423 Other liabilities $ 1,423 $ — Interest rate swaps 50 — 50 Other liabilities 50 — Foreign currency forward contracts (1) 3,808 28 3,780 Other liabilities — 3,780 Foreign currency forward contracts (2) 939 622 317 Other liabilities — 317 Total derivative instruments not designated as hedges 6,342 772 5,570 1,473 4,097 Derivative instruments designated as hedges Foreign currency forward contracts (3) 1,818 — 1,818 Other liabilities — 1,818 Total $ 8,160 $ 772 $ 7,388 $ 1,473 $ 5,915 (1) Contracts used to manage foreign currency risks in underwriting and non-investment operations. (2) Contracts used to manage foreign currency risks in investment operations. (3) Contracts designated as hedges of a net investment in a foreign operation. Derivative Assets At December 31, 2018 Gross Amounts of Recognized Assets Gross Amounts Offset in the Balance Sheet Net Amounts of Assets Presented in the Balance Sheet Balance Sheet Location Collateral Net Amount Derivative instruments not designated as hedges Interest rate futures $ 971 $ 636 $ 335 Other assets $ — $ 335 Interest rate swaps 860 — 860 Other assets — 860 Foreign currency forward contracts (1) 16,459 2,260 14,199 Other assets — 14,199 Foreign currency forward contracts (2) 3,194 71 3,123 Other assets — 3,123 Equity futures 1,390 977 413 Other assets — 413 Total $ 22,874 $ 3,944 $ 18,930 $ — $ 18,930 Derivative Liabilities At December 31, 2018 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Balance Sheet Net Amounts of Liabilities Presented in the Balance Sheet Balance Sheet Location Collateral Pledged Net Amount Derivative instruments not designated as hedges Interest rate futures $ 910 $ 636 $ 273 Other liabilities $ 273 $ — Interest rate swaps 506 — 506 Other liabilities 254 252 Foreign currency forward contracts (1) 4,154 — 4,154 Other liabilities — 4,154 Foreign currency forward contracts (2) 72 71 1 Other liabilities — 1 Credit default swaps 1,606 — 1,606 Other liabilities 1,605 1 Equity futures 977 977 — Other liabilities — — Total $ 8,225 $ 1,684 $ 6,540 $ 2,132 $ 4,408 (1) Contracts used to manage foreign currency risks in underwriting and non-investment operations. (2) Contracts used to manage foreign currency risks in investment operations. Refer to “Note 5 . Investments” for information on reverse repurchase agreements. The location and amount of the gain (loss) recognized in the Company’s consolidated statements of operations related to its principal derivative instruments are shown in the following table: Location of gain (loss) recognized on derivatives Amount of gain (loss) recognized on derivatives Year ended December 31, 2019 2018 2017 Derivative instruments not designated as hedges Interest rate futures Net realized and unrealized gains (losses) on investments $ 16,848 $ 6,109 $ (3,252 ) Interest rate swaps Net realized and unrealized gains (losses) on investments 1,488 (84 ) 436 Foreign currency forward contracts (1) Net foreign exchange losses 12,617 3,840 9,628 Foreign currency forward contracts (2) Net foreign exchange losses (1,605 ) 5,736 (916 ) Credit default swaps Net realized and unrealized gains (losses) on investments 7,043 (3,106 ) 326 Total return swaps Net realized and unrealized gains (losses) on investments 12,155 — — Equity futures Net realized and unrealized gains (losses) on investments 21,357 (515 ) — Total derivative instruments not designated as hedges 69,903 11,980 6,222 Derivative instruments designated as hedges Foreign currency forward contracts (3) Accumulated other comprehensive income (loss) 959 — — Total $ 70,862 $ 11,980 $ 6,222 (1) Contracts used to manage foreign currency risks in underwriting and non-investment operations. (2) Contracts used to manage foreign currency risks in investment operations. (3) Contracts designated as hedges of a net investment in a foreign operation. The Company is not aware of the existence of any credit-risk related contingent features that it believes would be triggered in its derivative instruments that are in a net liability position at December 31, 2019 . Derivative Instruments Not Designated as Hedges Interest Rate Derivatives The Company uses interest rate futures and swaps within its portfolio of fixed maturity investments to manage its exposure to interest rate risk, which may result in increasing or decreasing its exposure to this risk. Interest Rate Futures The fair value of interest rate futures is determined using exchange traded prices. At December 31, 2019 , the Company had $2.5 billion of notional long positions and $1.0 billion of notional short positions of primarily Eurodollar and U.S. treasury futures contracts ( 2018 – $1.9 billion and $545.8 million , respectively). Interest Rate Swaps The fair value of interest rate swaps is determined using the relevant exchange traded price where available or a discounted cash flow model based on the terms of the contract and inputs, including, where applicable, observable yield curves. At December 31, 2019 , the Company had $27.9 million of notional positions paying a fixed rate and $25.5 million receiving a fixed rate denominated in U.S. dollar swap contracts ( 2018 - $78.4 million and $32.1 million , respectively). Foreign Currency Derivatives The Company’s functional currency is the U.S. dollar. The Company writes a portion of its business in currencies other than U.S. dollars and may, from time to time, experience foreign exchange gains and losses in the Company’s consolidated financial statements. All changes in exchange rates, with the exception of non-monetary assets and liabilities, are recognized in the Company’s consolidated statements of operations. Underwriting and Non-Investments Operations Related Foreign Currency Contracts The Company’s foreign currency policy with regard to its underwriting operations is generally to hold foreign currency assets, including cash, investments and receivables that approximate the foreign currency liabilities, including claims and claim expense reserves and reinsurance balances payable. When necessary, the Company may use foreign currency forward and option contracts to minimize the effect of fluctuating foreign currencies on the value of non-U.S. dollar denominated assets and liabilities associated with its underwriting operations. The fair value of the Company’s underwriting operations related foreign currency contracts is determined using indicative pricing obtained from counterparties or broker quotes. At December 31, 2019 , the Company had outstanding underwriting related foreign currency contracts of $722.6 million in notional long positions and $1.2 billion in notional short positions, denominated in U.S. dollars ( 2018 – $354.1 million and $601.2 million , respectively). Investment Portfolio Related Foreign Currency Forward Contracts The Company’s investment operations are exposed to currency fluctuations through its investments in non-U.S. dollar fixed maturity investments, short term investments and other investments. From time to time, the Company may employ foreign currency forward contracts in its investment portfolio to either assume foreign currency risk or to economically hedge its exposure to currency fluctuations from these investments. The fair value of the Company’s investment portfolio related foreign currency forward contracts is determined using an interpolated rate based on closing forward market rates. At December 31, 2019 , the Company had outstanding investment portfolio related foreign currency contracts of $195.6 million in notional long positions and $61.0 million in notional short positions, denominated in U.S. dollars ( 2018 – $121.3 million and $42.9 million , respectively). Credit Derivatives The Company’s exposure to credit risk is primarily due to its fixed maturity investments, short term investments, premiums receivable and reinsurance recoverable. From time to time, the Company may purchase credit derivatives to hedge its exposures in the insurance industry, and to assist in managing the credit risk associated with ceded reinsurance. The Company also employs credit derivatives in its investment portfolio to either assume credit risk or hedge its credit exposure. Credit Default Swaps The fair value of the Company credit default swaps is determined using industry valuation models, broker bid indications or internal pricing valuation techniques. The fair value of these credit default swaps can change based on a variety of factors including changes in credit spreads, default rates and recovery rates, the correlation of credit risk between the referenced credit and the counterparty, and market rate inputs such as interest rates. At December 31, 2019 , the Company had outstanding credit default swaps of $0.5 million in notional positions to hedge credit risk and $143.4 million in notional positions to assume credit risk, denominated in U.S. dollars ( 2018 – $1.0 million and $126.2 million , respectively). Total Return Swaps During 2019 , the Company entered into certain total return swap contracts. The Company uses total return swaps as a means to manage spread duration and credit exposure in its investment portfolio. The fair value of the Company’s total return swaps is determined using broker-dealer bid quotations, market-based prices from pricing vendors or valuation models. At December 31, 2019 , the Company had $173.5 million of notional long positions (long credit) and $Nil of notional short positions (short credit), denominated in U.S. dollars. Equity Derivatives Equity Futures The Company uses equity derivatives in its investment portfolio from time to time to either assume equity risk or hedge its equity exposure. The fair value of the Company’s equity futures is determined using market-based prices from pricing vendors. At December 31, 2019 , the Company had $122.0 million notional long position and $Nil notional short position of equity futures, denominated in U.S. dollars ( 2018 - $44.7 million and $Nil , respectively). Derivative Instruments Designated as Hedges of a Net Investment in a Foreign Operation Foreign Currency Derivatives Hedges of a Net Investment in a Foreign Operation In connection with the acquisition of TMR, the Company acquired certain entities with non-U.S. dollar functional currencies, including RenaissanceRe Europe, Australia Branch, which has an Australian dollar functional currency. The Company has entered into foreign exchange forwards to hedge the Australian dollar net investment in foreign operations, on an after-tax basis, from changes in the exchange rate between the U.S. dollar and the Australian dollar. The Company utilizes foreign exchange forward contracts to hedge the fair value of its net investment in a foreign operation. During 2019 , the Company entered into foreign exchange forward contracts that were formally designated as hedges of its investment in RenaissanceRe Europe, Australia Branch. There was no ineffectiveness in these transactions. The table below provides a summary of derivative instruments designated as hedges of a net investment in a foreign operation, including the weighted average U.S. dollar equivalent of foreign denominated net assets that were hedged and the resulting derivative gain that was recorded in foreign currency translation adjustments, net of tax, within accumulated other comprehensive income (loss) on the Company’s consolidated statements of changes in shareholders’ equity: Year ended December 31, 2019 2018 Weighted average of U.S. dollar equivalent of foreign denominated net assets $ 81,264 $ — Derivative gains (1) $ 959 $ — (1) Derivative gains from derivative instruments designated as hedges of the net investment in a foreign operation are recorded in foreign currency translation adjustments, net of tax, within accumulated other comprehensive income (loss) on the Company’s consolidated statements of changes in shareholders’ equity.

Commitments, Contingencies and

Commitments, Contingencies and Other Items	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Other Items	COMMITMENTS, CONTINGENCIES AND OTHER ITEMS Concentration of Credit Risk Instruments which potentially subject the Company to concentration of credit risk consist principally of investments, including the Company’s equity method investments, cash, premiums receivable and reinsurance balances. The Company limits the amount of credit exposure to any one financial institution and, except for the securities of the U.S. Government and U.S. Government related entities, and money market securities, none of the Company’s investments exceeded 10% of shareholders’ equity at December 31, 2019 . Refer to “Note 7 . Reinsurance,” for information with respect to reinsurance recoverable. Employment Agreements The Board of Directors has authorized the execution of employment agreements between the Company and certain officers. These agreements provide for, among other things, severance payments under certain circumstances, as well as accelerated vesting of options and certain restricted stock grants, upon a change in control, as defined in the employment agreements and the Company’s stock incentive plans. Letters of Credit and Other Commitments At December 31, 2019 , the Company’s banks have issued letters of credit of $1.1 billion in favor of certain ceding companies. In connection with the Company’s Top Layer Re joint venture, Renaissance Reinsurance has committed $37.5 million of collateral to support a letter of credit and is obligated to make a mandatory capital contribution of up to $50.0 million in the event that a loss reduces Top Layer Re’s capital and surplus below a specified level. The letters of credit are secured by cash and investments of similar amounts. Refer to “Note 9 . Debt and Credit Facilities” for additional information related to the Company’s debt and credit facilities. Private Equity and Investment Commitments The Company has committed capital to private equity investments, other investments and investments in other ventures of $1.1 billion , of which $708.4 million has been contributed at December 31, 2019 . The Company’s remaining commitments to these investments at December 31, 2019 totaled $411.3 million . These commitments do not have a defined contractual commitment date. Indemnifications and Warranties In the ordinary course of its business, the Company may enter into contracts or agreements that contain indemnifications or warranties. Future events could occur that lead to the execution of these provisions against the Company. Based on past experience, management currently believes that the likelihood of such an event is remote. Leases The Company’s operating leases primarily relate to office space for its global underwriting platforms principally in Bermuda, Australia, Ireland, Singapore, Switzerland, the U.K. and the U.S. These leases expire at various dates through 2029 with a weighted average lease term of 4.0 years . Included in other assets and other liabilities at December 31, 2019 is a right-to-use asset of $42.8 million and a lease liability of $42.9 million , respectively, associated with the Company’s operating leases and reflected as a result of the Company’s adoption of FASB ASC Topic Leases ( 2018 - $Nil and $Nil , respectively). During 2019 , the Company recorded an operating lease expense of $8.5 million included in operating expenses ( 2018 - $6.1 million ). The Company’s financing leases primarily relate to office space in Bermuda with an initial lease term of 20 years, ending in 2028 , and a bargain renewal option for an additional 30 years. Included in other assets and other liabilities at December 31, 2019 is a right-to-use asset of $19.8 million and a lease liability of $25.1 million , respectively, associated with the Company’s finance leases ( 2018 - $20.6 million and $25.6 million , respectively). During 2019 , the Company recorded interest expense of $2.6 million associated with its finance leases ( 2018 - $2.6 million ) included in other income and amortization of its finance leases right-to-use asset of $0.9 million included in operating expenses ( 2018 - $0.9 million ). Future minimum lease payments under existing operating and finance leases are detailed below, excluding the bargain renewal option on the finance lease related to office space in Bermuda: Future minimum lease payments Operating leases Finance leases 2020 $ 7,912 $ 3,336 2021 7,684 3,336 2022 6,967 3,336 2023 3,959 2,830 2024 2,850 2,661 After 2024 11,285 10,129 Future minimum lease payments under existing leases $ 40,657 $ 25,628 Legal Proceedings The Company and its subsidiaries are subject to lawsuits and regulatory actions in the normal course of business that do not arise from or directly relate to claims on reinsurance treaties or contracts or direct surplus lines insurance policies. In the Company’s industry, business litigation may involve allegations of underwriting or claims-handling errors or misconduct, disputes relating to the scope of, or compliance with, the terms of delegated underwriting agreements, employment claims, regulatory actions or disputes arising from the Company’s business ventures. The Company’s operating subsidiaries are subject to claims litigation involving, among other things, disputed interpretations of policy coverages. Generally, the Company’s direct surplus lines insurance operations are subject to greater frequency and diversity of claims and claims-related litigation than its reinsurance operations and, in some jurisdictions, may be subject to direct actions by allegedly injured persons or entities seeking damages from policyholders. These lawsuits, involving or arising out of claims on policies issued by the Company’s subsidiaries which are typical to the insurance industry in general and in the normal course of business, are considered in its loss and loss expense reserves. In addition, the Company may from time to time engage in litigation or arbitration related to its claims for payment in respect of ceded reinsurance, including disputes that challenge the Company’s ability to enforce its underwriting intent. Such matters could result, directly or indirectly, in providers of protection not meeting their obligations to the Company or not doing so on a timely basis. The Company may also be subject to other disputes from time to time, relating to operational or other matters distinct from insurance or reinsurance claims. Any litigation or arbitration, or regulatory process, contains an element of uncertainty, and the value of an exposure or a gain contingency related to a dispute is difficult to estimate. The Company believes that no individual litigation or arbitration to which it is presently a party is likely to have a material adverse effect on its financial condition, business or operations.

Quarterly Financial Information

Quarterly Financial Information (Unaudited)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Data [Abstract]
Quarterly Financial Information (Unaudited)	QUARTERLY FINANCIAL INFORMATION (UNAUDITED) Quarter Ended March 31, Quarter Ended June 30, Quarter Ended September 30, Quarter Ended December 31, 2019 2018 2019 2018 2019 2018 2019 2018 Revenues Gross premiums written $ 1,564,295 $ 1,159,652 $ 1,476,908 $ 977,343 $ 861,068 $ 625,677 $ 905,479 $ 547,755 Net premiums written $ 929,031 $ 663,044 $ 1,022,965 $ 604,509 $ 704,130 $ 453,255 $ 725,367 $ 411,094 (Increase) decrease in unearned premiums (379,003 ) (222,762 ) (111,463 ) (175,124 ) 202,618 78,594 244,758 163,519 Net premiums earned 550,028 440,282 911,502 429,385 906,748 531,849 970,125 574,613 Net investment income 81,462 56,476 115,832 71,356 113,844 80,696 112,695 53,338 Net foreign exchange (losses) gains (2,846 ) 3,757 9,309 (10,687 ) (8,275 ) (4,566 ) (1,126 ) (932 ) Equity in earnings of other ventures 4,661 857 6,812 5,826 5,877 7,648 5,874 4,143 Other income (loss) 3,171 (1,242 ) 922 1,225 1,016 497 (160 ) 5,489 Net realized and unrealized gains (losses) on investments 170,645 (82,144 ) 194,003 (17,901 ) 31,938 13,630 17,897 (88,654 ) Total revenues 807,121 417,986 1,238,380 479,204 1,051,148 629,754 1,105,305 547,997 Expenses Net claims and claim expenses incurred 227,035 171,703 453,373 60,167 654,520 410,510 762,093 477,638 Acquisition costs 123,951 97,711 227,482 105,052 202,181 109,761 208,618 120,465 Operational expenses 44,933 41,272 59,814 37,543 53,415 40,593 64,571 58,859 Corporate expenses 38,789 6,733 23,847 8,301 13,844 6,841 17,642 12,108 Interest expense 11,754 11,767 15,534 11,768 15,580 11,769 15,496 11,765 Total expenses 446,462 329,186 780,050 222,831 939,540 579,474 1,068,420 680,835 Income (loss) before taxes 360,659 88,800 458,330 256,373 111,608 50,280 36,885 (132,838 ) Income tax (expense) benefit (7,531 ) 3,407 (9,475 ) (4,506 ) (3,664 ) (1,451 ) 3,455 8,852 Net income (loss) 353,128 92,207 448,855 251,867 107,944 48,829 40,340 (123,986 ) Net (income) loss attributable to redeemable noncontrolling interests (70,222 ) (29,899 ) (71,812 ) (54,483 ) (62,057 ) (6,440 ) 2,622 49,269 Net income (loss) available (attributable) to RenaissanceRe 282,906 62,308 377,043 197,384 45,887 42,389 42,962 (74,717 ) Dividends on preference shares (9,189 ) (5,595 ) (9,189 ) (5,596 ) (9,189 ) (9,708 ) (9,189 ) (9,189 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders $ 273,717 $ 56,713 $ 367,854 $ 191,788 $ 36,698 $ 32,681 $ 33,773 $ (83,906 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – basic $ 6.43 $ 1.42 $ 8.36 $ 4.78 $ 0.83 $ 0.82 $ 0.77 $ (2.10 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – diluted $ 6.43 $ 1.42 $ 8.35 $ 4.78 $ 0.83 $ 0.82 $ 0.77 $ (2.10 ) Average shares outstanding – basic 42,065 39,552 43,483 39,641 43,462 39,624 43,467 40,111 Average shares outstanding – diluted 42,091 39,599 43,521 39,654 43,537 39,637 43,552 40,111

Condensed Consolidating Financi

Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries	12 Months Ended
	Dec. 31, 2019
Condensed Consolidating Financial Information Provided In Connection With Outstanding Debt Of Subsidiaries [Abstract]
Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries	CONDENSED CONSOLIDATING FINANCIAL INFORMATION PROVIDED IN CONNECTION WITH OUTSTANDING DEBT OF SUBSIDIARIES The following tables are provided in connection with outstanding debt of the Company’s subsidiaries and present condensed consolidating balance sheets at December 31, 2019 and 2018 , condensed consolidating statements of operations, condensed consolidating statements of comprehensive income (loss) and condensed consolidating statements of cash flows for the years ended December 31, 2019 , 2018 and 2017 , respectively. Each of RRNAH and RenaissanceRe Finance is a 100% owned subsidiary of RenaissanceRe and has outstanding debt securities. On June 1, 2017, the Platinum Finance Notes matured and the Company repaid the aggregate principal amount plus applicable accrued interest in full. Platinum Finance was subsequently dissolved on November 30, 2017. Prior to the liquidation of Platinum Finance, it was a 100% owned subsidiary of RenaissanceRe and had outstanding debt securities. For additional information related to the terms of the Company’s outstanding debt securities, see “Note 9 . Debt and Credit Facilities.” Condensed Consolidating Balance Sheet at December 31, 2019 RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Assets Total investments $ 190,451 $ 123,792 $ 288,137 $ 16,766,409 $ — $ 17,368,789 Cash and cash equivalents 26,460 9,440 8,731 1,334,437 — 1,379,068 Investments in subsidiaries 5,204,260 48,247 1,426,838 — (6,679,345 ) — Due from subsidiaries and affiliates 10,725 101,579 — — (112,304 ) — Premiums receivable — — — 2,599,896 — 2,599,896 Prepaid reinsurance premiums — — — 767,781 — 767,781 Reinsurance recoverable — — — 2,791,297 — 2,791,297 Accrued investment income — 270 1,171 71,020 — 72,461 Deferred acquisition costs and value of business acquired — — — 663,991 — 663,991 Receivable for investments sold 173 — — 78,196 — 78,369 Other assets 847,406 10,978 12,211 301,578 (825,957 ) 346,216 Goodwill and other intangible assets 116,212 — — 146,014 — 262,226 Total assets $ 6,395,687 $ 294,306 $ 1,737,088 $ 25,520,619 $ (7,617,606 ) $ 26,330,094 Liabilities, Noncontrolling Interests and Shareholders’ Equity Liabilities Reserve for claims and claim expenses $ — $ — $ — $ 9,384,349 $ — $ 9,384,349 Unearned premiums — — — 2,530,975 — 2,530,975 Debt 391,475 — 970,255 148,349 (125,974 ) 1,384,105 Amounts due to subsidiaries and affiliates 6,708 51 102,493 — (109,252 ) — Reinsurance balances payable — — — 2,830,691 — 2,830,691 Payable for investments purchased — — — 225,275 — 225,275 Other liabilities 26,137 278 14,162 899,682 (8,235 ) 932,024 Total liabilities 424,320 329 1,086,910 16,019,321 (243,461 ) 17,287,419 Redeemable noncontrolling interests — — — 3,071,308 — 3,071,308 Shareholders’ Equity Total shareholders’ equity 5,971,367 293,977 650,178 6,429,990 (7,374,145 ) 5,971,367 Total liabilities, noncontrolling interests and shareholders’ equity $ 6,395,687 $ 294,306 $ 1,737,088 $ 25,520,619 $ (7,617,606 ) $ 26,330,094 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Balance Sheet at December 31, 2018 RenaissanceRe Holdings Ltd. (Parent Guarantor) RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) Consolidating Adjustments (2) RenaissanceRe Consolidated Assets Total investments $ 313,360 $ 77,842 $ 28,885 $ 11,465,660 $ — $ 11,885,747 Cash and cash equivalents 3,534 3,350 9,604 1,091,434 — 1,107,922 Investments in subsidiaries 4,414,475 58,458 1,215,663 — (5,688,596 ) — Due from subsidiaries and affiliates 57,039 101,579 — — (158,618 ) — Premiums receivable — — — 1,537,188 — 1,537,188 Prepaid reinsurance premiums — — — 616,185 — 616,185 Reinsurance recoverable — — — 2,372,221 — 2,372,221 Accrued investment income 1,046 310 127 49,828 — 51,311 Deferred acquisition costs — — — 476,661 — 476,661 Receivable for investments sold 203 23,885 — 232,328 — 256,416 Other assets 458,842 22,571 313,636 (1,403,636 ) 743,714 135,127 Goodwill and other intangible assets 120,476 — — 116,942 — 237,418 Total assets $ 5,368,975 $ 287,995 $ 1,567,915 $ 16,554,811 $ (5,103,500 ) $ 18,676,196 Liabilities, Redeemable Noncontrolling Interest and Shareholders’ Equity Liabilities Reserve for claims and claim expenses $ — $ — $ — $ 6,076,271 $ — $ 6,076,271 Unearned premiums — — — 1,716,021 — 1,716,021 Debt 300,000 — 843,086 148,041 (300,000 ) 991,127 Amounts due to subsidiaries and affiliates 6,453 217 102,243 — (108,913 ) — Reinsurance balances payable — — — 1,902,056 — 1,902,056 Payable for investments purchased — 24 — 380,308 — 380,332 Other liabilities 17,442 5,362 13,918 482,422 (5,535 ) 513,609 Total liabilities 323,895 5,603 959,247 10,705,119 (414,448 ) 11,579,416 Redeemable noncontrolling interests — — — 2,051,700 — 2,051,700 Shareholders’ Equity Total shareholders’ equity 5,045,080 282,392 608,668 3,797,992 (4,689,052 ) 5,045,080 Total liabilities, redeemable noncontrolling interest and shareholders’ equity $ 5,368,975 $ 287,995 $ 1,567,915 $ 16,554,811 $ (5,103,500 ) $ 18,676,196 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Operations for RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Revenues Net premiums earned $ — $ — $ — $ 3,338,403 $ — $ 3,338,403 Net investment income 39,629 2,318 7,547 419,502 (45,163 ) 423,833 Net foreign exchange gains (losses) 7,342 — — (10,280 ) — (2,938 ) Equity in earnings of other ventures — — 3,886 19,338 — 23,224 Other income — — — 4,949 — 4,949 Net realized and unrealized gains on investments 12,393 21,557 151 380,382 — 414,483 Total revenues 59,364 23,875 11,584 4,152,294 (45,163 ) 4,201,954 Expenses Net claims and claim expenses incurred — — — 2,097,021 — 2,097,021 Acquisition expenses — — — 762,232 — 762,232 Operational expenses 7,506 56 38,487 207,981 (31,297 ) 222,733 Corporate expenses 58,393 — 16 43,413 (7,700 ) 94,122 Interest expense 18,086 — 37,993 2,285 — 58,364 Total expenses 83,985 56 76,496 3,112,932 (38,997 ) 3,234,472 (Loss) income before equity in net income of subsidiaries and taxes (24,621 ) 23,819 (64,912 ) 1,039,362 (6,166 ) 967,482 Equity in net income of subsidiaries 773,419 5,611 99,148 — (878,178 ) — Income before taxes 748,798 29,430 34,236 1,039,362 (884,344 ) 967,482 Income tax (expense) benefit — (4,872 ) 6,510 (18,853 ) — (17,215 ) Net income 748,798 24,558 40,746 1,020,509 (884,344 ) 950,267 Net income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Net income attributable to RenaissanceRe 748,798 24,558 40,746 819,040 (884,344 ) 748,798 Dividends on preference shares (36,756 ) — — — — (36,756 ) Net income available to RenaissanceRe common shareholders $ 712,042 $ 24,558 $ 40,746 $ 819,040 $ (884,344 ) $ 712,042 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Comprehensive Income for the year ended December 31, 2019 RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Comprehensive income Net income $ 748,798 $ 24,558 $ 40,746 $ 1,020,509 $ (884,344 ) $ 950,267 Change in net unrealized gains on investments, net of tax 2,173 528 764 — (1,292 ) 2,173 Foreign currency translation adjustments, net of tax (2,679 ) — — — — (2,679 ) Comprehensive income 748,292 25,086 41,510 1,020,509 (885,636 ) 949,761 Net income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Comprehensive income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Comprehensive income available to RenaissanceRe $ 748,292 $ 25,086 $ 41,510 $ 819,040 $ (885,636 ) $ 748,292 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Operations for the year ended December 31, 2018 RenaissanceRe RenRe North Inc. RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Revenues Net premiums earned $ — $ — $ — $ 1,976,129 $ — $ 1,976,129 Net investment income 24,791 2,193 6,219 261,192 (32,529 ) 261,866 Net foreign exchange losses (3 ) — — (12,425 ) — (12,428 ) Equity in earnings of other ventures — — 3,065 15,409 — 18,474 Other income — — — 5,969 — 5,969 Net realized and unrealized gains (losses) on investments 633 (4,360 ) (329 ) (171,013 ) — (175,069 ) Total revenues 25,421 (2,167 ) 8,955 2,075,261 (32,529 ) 2,074,941 Expenses Net claims and claim expenses incurred — — — 1,120,018 — 1,120,018 Acquisition expenses — — — 432,989 — 432,989 Operational expenses 7,679 110 34,534 164,605 (28,661 ) 178,267 Corporate expenses 25,190 — 7 3,103 5,683 33,983 Interest expense 5,683 — 37,019 4,367 — 47,069 Total expenses 38,552 110 71,560 1,725,082 (22,978 ) 1,812,326 (Loss) income before equity in net income (loss) of subsidiaries and taxes (13,131 ) (2,277 ) (62,605 ) 350,179 (9,551 ) 262,615 Equity in net income (loss) of subsidiaries 240,495 5,631 9,091 — (255,217 ) — Income (loss) before taxes 227,364 3,354 (53,514 ) 350,179 (264,768 ) 262,615 Income tax benefit (expense) — 582 6,119 (399 ) — 6,302 Net income (loss) 227,364 3,936 (47,395 ) 349,780 (264,768 ) 268,917 Net income attributable to redeemable noncontrolling interests — — — (41,553 ) — (41,553 ) Net income (loss) attributable to RenaissanceRe 227,364 3,936 (47,395 ) 308,227 (264,768 ) 227,364 Dividends on preference shares (30,088 ) — — — — (30,088 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders $ 197,276 $ 3,936 $ (47,395 ) $ 308,227 $ (264,768 ) $ 197,276 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Comprehensive Income (Loss) for the year ended December 31, 2018 RenaissanceRe RenRe North Inc. RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Comprehensive income (loss) Net income (loss) $ 227,364 $ 3,936 $ (47,395 ) $ 349,780 $ (264,768 ) $ 268,917 Change in net unrealized gains on investments, net of tax (1,657 ) (160 ) (162 ) — 322 (1,657 ) Comprehensive income (loss) 225,707 3,776 (47,557 ) 349,780 (264,446 ) 267,260 Net income attributable to redeemable noncontrolling interests — — — (41,553 ) — (41,553 ) Comprehensive income attributable to redeemable noncontrolling interests — — — (41,553 ) — (41,553 ) Comprehensive income (loss) available (attributable) to RenaissanceRe $ 225,707 $ 3,776 $ (47,557 ) $ 308,227 $ (264,446 ) $ 225,707 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Operations RenaissanceRe Holdings Ltd. (Parent Guarantor) RenRe North America Holdings Inc. (Subsidiary Issuer) Platinum RenaissanceRe Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) Consolidating Adjustments (2) RenaissanceRe Consolidated Revenues Net premiums earned $ — $ — $ — $ — $ 1,717,575 $ — $ 1,717,575 Net investment income 23,109 1,947 1,373 3,090 219,490 (26,800 ) 222,209 Net foreign exchange (losses) gains (1 ) — — — 10,629 — 10,628 Equity in (losses) earnings of other ventures — — — (223 ) 8,253 — 8,030 Other income — — — — 9,415 — 9,415 Net realized and unrealized (losses) gains on investments (1,357 ) 9,621 4,916 (479 ) 123,121 — 135,822 Total revenues 21,751 11,568 6,289 2,388 2,088,483 (26,800 ) 2,103,679 Expenses Net claims and claim expenses incurred — — — — 1,861,428 — 1,861,428 Acquisition expenses — — — — 346,892 — 346,892 Operational expenses 11,314 103 85 26,063 141,572 (18,359 ) 160,778 Corporate expenses 18,546 — — — 26 — 18,572 Interest expense 1,572 — 2,461 31,657 10,075 (1,572 ) 44,193 Total expenses 31,432 103 2,546 57,720 2,359,993 (19,931 ) 2,431,863 (Loss) income before equity in net (loss) income of subsidiaries and taxes (9,681 ) 11,465 3,743 (55,332 ) (271,510 ) (6,869 ) (328,184 ) Equity in net (loss) income of subsidiaries (212,708 ) 756 28,028 9,298 — 174,626 — (Loss) income before taxes (222,389 ) 12,221 31,771 (46,034 ) (271,510 ) 167,757 (328,184 ) Income tax (expense) benefit — (18,147 ) (1,175 ) 7,163 (14,328 ) — (26,487 ) Net (loss) income (222,389 ) (5,926 ) 30,596 (38,871 ) (285,838 ) 167,757 (354,671 ) Net loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Net (loss) income attributable to RenaissanceRe (222,389 ) (5,926 ) 30,596 (38,871 ) (153,556 ) 167,757 (222,389 ) Dividends on preference shares (22,381 ) — — — — — (22,381 ) Net (loss) income (attributable) available to RenaissanceRe common shareholders $ (244,770 ) $ (5,926 ) $ 30,596 $ (38,871 ) $ (153,556 ) $ 167,757 $ (244,770 ) (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Comprehensive Income (Loss) for the year ended December 31, 2017 RenaissanceRe Holdings Ltd. (Parent Guarantor) RenRe North America Holdings Inc. (Subsidiary Issuer) Platinum RenaissanceRe Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) Consolidating Adjustments (2) RenaissanceRe Consolidated Comprehensive (loss) income Net (loss) income $ (222,389 ) $ (5,926 ) $ 30,596 $ (38,871 ) $ (285,838 ) $ 167,757 $ (354,671 ) Change in net unrealized gains on investments, net of tax (909 ) (89 ) — (89 ) — 178 (909 ) Comprehensive (loss) income (223,298 ) (6,015 ) 30,596 (38,960 ) (285,838 ) 167,935 (355,580 ) Net loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Comprehensive loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Comprehensive (loss) income (attributable) available to RenaissanceRe $ (223,298 ) $ (6,015 ) $ 30,596 $ (38,960 ) $ (153,556 ) $ 167,935 $ (223,298 ) (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Cash Flows for the year ended December 31, 2019 RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Consolidated Cash flows (used in) provided by operating activities Net cash (used in) provided by operating activities $ (2,861 ) $ 3,872 $ 366,934 $ 1,769,250 $ 2,137,195 Cash flows provided by (used in) investing activities Proceeds from sales and maturities of fixed maturity investments trading 306,579 77,798 60,737 16,868,826 17,313,940 Purchases of fixed maturity investments trading (66,740 ) (77,145 ) (33,577 ) (17,741,881 ) (17,919,343 ) Net purchases of equity investments trading — (3,358 ) — (4,483 ) (7,841 ) Net (purchases) sales of short term investments (116,499 ) 739 (283,717 ) (1,501,264 ) (1,900,741 ) Net purchases of other investments — — — (202,878 ) (202,878 ) Net purchases of investments in other ventures — — — (2,717 ) (2,717 ) Return of investment from investment in other ventures — — — 11,250 11,250 Net sales of other assets — — — (4,108 ) (4,108 ) Dividends and return of capital from subsidiaries 1,400,944 4,350 13,500 (1,418,794 ) — Contributions to subsidiaries (1,165,607 ) — (125,000 ) 1,290,607 — Due (from) to subsidiary (625,924 ) (166 ) 250 625,840 — Net purchase of TMR — — — (276,206 ) (276,206 ) Net cash provided by (used in) investing activities (267,247 ) 2,218 (367,807 ) (2,355,808 ) (2,988,644 ) Cash flows provided by financing activities Dividends paid – RenaissanceRe common shares (59,368 ) — — — (59,368 ) Dividends paid – preference shares (36,756 ) — — — (36,756 ) Issuance of debt, net of expenses 396,411 — — — 396,411 Net third-party redeemable noncontrolling interest share transactions — — — 827,083 827,083 Taxes paid on withholding shares (7,253 ) — — — (7,253 ) Net cash provided by financing activities 293,034 — — 827,083 1,120,117 Effect of exchange rate changes on foreign currency cash — — — 2,478 2,478 Net increase (decrease) in cash and cash equivalents 22,926 6,090 (873 ) 243,003 271,146 Cash and cash equivalents, beginning of period 3,534 3,350 9,604 1,091,434 1,107,922 Cash and cash equivalents, end of period $ 26,460 $ 9,440 $ 8,731 $ 1,334,437 $ 1,379,068 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. Condensed Consolidating Statement of Cash Flows for the year ended December 31, 2018 RenaissanceRe RenRe North Inc. RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) RenaissanceRe Consolidated Cash flows (used in) provided by operating activities Net cash (used in) provided by operating activities $ 17,187 $ 6,315 $ 62,645 $ 1,135,554 $ 1,221,701 Cash flows used in investing activities Proceeds from sales and maturities of fixed maturity investments trading 384,818 97,272 56,518 11,046,968 11,585,576 Purchases of fixed maturity investments trading (520,935 ) (72,292 ) (55,932 ) (11,840,813 ) (12,489,972 ) Net (purchases) sales of equity investments trading — (1,308 ) — 15,464 14,156 Net sales (purchases) of short term investments 48,600 (404 ) 455 (1,485,040 ) (1,436,389 ) Net purchases of other investments — — — (199,475 ) (199,475 ) Net purchases of investments in other ventures — — — (21,473 ) (21,473 ) Return of investment from investment in other ventures — — — 8,464 8,464 Net sales of other assets — — — 2,500 2,500 Dividends and return of capital from subsidiaries 672,098 — — (672,098 ) — Contributions to subsidiaries (785,785 ) (16,847 ) (65,000 ) 867,632 — Due to (from) subsidiaries (227,762 ) (9,525 ) 9,449 227,838 — Net cash used in investing activities (428,966 ) (3,104 ) (54,510 ) (2,050,033 ) (2,536,613 ) Cash flows provided by financing activities Dividends paid – RenaissanceRe common shares (52,841 ) — — — (52,841 ) Dividends paid – preference shares (30,088 ) — — — (30,088 ) RenaissanceRe common share issuance 250,000 — — — 250,000 Issuance of preference shares, net of expenses 241,448 — — — 241,448 Net third-party redeemable noncontrolling interest share transactions — — — 665,683 665,683 Taxes paid on withholding shares (7,862 ) — — — (7,862 ) Net cash provided by financing activities 400,657 — — 665,683 1,066,340 Effect of exchange rate changes on foreign currency cash — — — (5,098 ) (5,098 ) Net (decrease) increase in cash and cash equivalents (11,122 ) 3,211 8,135 (253,894 ) (253,670 ) Cash and cash equivalents, beginning of period 14,656 139 1,469 1,345,328 1,361,592 Cash and cash equivalents, end of period $ 3,534 $ 3,350 $ 9,604 $ 1,091,434 $ 1,107,922 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. Condensed Consolidating Statement of Cash Flows for the year ended December 31, 2017 RenaissanceRe RenRe North Platinum Underwriters Finance, Inc. (Subsidiary Issuer) RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Cash flows (used in) provided by operating activities Net cash (used in) provided by operating activities $ 21,118 $ (8,253 ) $ (2,272 ) $ (347,890 ) $ 1,363,084 $ 1,025,787 Cash flows provided by (used in) investing activities Proceeds from sales and maturities of fixed maturity investments trading 261,601 100,248 289,741 288,900 8,550,179 9,490,669 Purchases of fixed maturity investments trading (344,463 ) (99,568 ) (143,991 ) (275,778 ) (9,229,732 ) (10,093,532 ) Net (purchases) sales of equity investments trading — (1,752 ) 85,324 — 32,265 115,837 Net sales (purchases) of short term investments 243,571 114 41,299 (493 ) 79,520 364,011 Net purchases of other investments — — — — (19,419 ) (19,419 ) Return of investment from investment in other ventures — — — — 20,000 20,000 Dividends and return of capital from subsidiaries 478,496 9,175 — 41,866 (529,537 ) — Contributions to subsidiaries (669,672 ) — (26,649 ) (9,890 ) 706,211 — Due to (from) subsidiary 294,419 13 (123 ) (509 ) (293,800 ) — Net cash provided by (used in) investing activities 263,952 8,230 245,601 44,096 (684,313 ) (122,434 ) Cash flows (used in) provided by financing activities Dividends paid – RenaissanceRe common shares (51,370 ) — — — — (51,370 ) Dividends paid – preference shares (22,381 ) — — — — (22,381 ) RenaissanceRe common share repurchases (188,591 ) — — — — (188,591 ) Net repayment of debt — — (250,000 ) — — (250,000 ) Issuance of debt, net of expenses — — — 295,866 — 295,866 Net third-party redeemable noncontrolling interest share transactions — — — — 260,475 260,475 Taxes paid on withholding shares (15,139 ) — — — — (15,139 ) Net cash (used in) provided by financing activities (277,481 ) — (250,000 ) 295,866 260,475 28,860 Effect of exchange rate changes on foreign currency cash — — — — 8,222 8,222 Net increase (decrease) in cash and cash equivalents 7,589 (23 ) (6,671 ) (7,928 ) 947,468 940,435 Cash and cash equivalents, beginning of year 7,067 162 6,671 9,397 397,860 421,157 Cash and cash equivalents, end of year $ 14,656 $ 139 $ — $ 1,469 $ 1,345,328 $ 1,361,592 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Effective January 1, 2020, Upsilon RFO issued $620.9 million of non-voting preference shares to investors, including $103.1 million to the Company. Of the total amount, $512.8 million was received by the Company prior to December 31, 2019. At December 31, 2019, $462.8 million , representing the amount received from investors other than the Company prior to December 31, 2019, is included in other liabilities on the Company’s consolidated balance sheet, and also included in other operating cash flows on the Company’s consolidated statements of cash flows for the year ended December 31, 2019. Effective January 1, 2020, the Company’s participation in the risks assumed by Upsilon RFO was 16.5% . Effective January 10, 2020, Mona Lisa Re issued two series of principal-at-risk variable rate notes to investors for a total principal amount of $400.0 million . On February 4, 2020, RenaissanceRe Specialty Holdings entered into an agreement to sell its wholly owned subsidiary, RenaissanceRe UK, a U.K. run-off company, to an investment vehicle managed by AXA Liabilities Managers, an affiliate of AXA XL. The sale is expected to close in 2020 and is subject to regulatory approval.

Schedule I. Summary of Investme

Schedule I. Summary of Investments Other Than Investments in Related Parties	12 Months Ended
	Dec. 31, 2019
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Abstract]
Summary of Investments, Other than Investments in Related Parties	SCHEDULE I RENAISSANCERE HOLDINGS LTD. AND SUBSIDIARIES SUMMARY OF INVESTMENTS OTHER THAN INVESTMENTS IN RELATED PARTIES (THOUSANDS OF UNITED STATES DOLLARS) December 31, 2019 Amortized Cost or Cost Fair Value Amount at which shown in the Balance Sheet Type of investment: Fixed maturity investments U.S. treasuries $ 4,439,533 $ 4,467,345 $ 4,467,345 Agencies 342,162 343,031 343,031 Non-U.S. government 495,465 497,392 497,392 Non-U.S. government-backed corporate 321,303 321,356 321,356 Corporate 3,010,615 3,075,660 3,075,660 Agency mortgage-backed 1,130,746 1,148,499 1,148,499 Non-agency mortgage-backed 282,267 294,604 294,604 Commercial mortgage-backed 489,352 468,698 468,698 Asset-backed 555,971 555,070 555,070 Total fixed maturity investments $ 11,067,414 11,171,655 11,171,655 Short term investments 4,566,277 4,566,277 Equity investments 436,931 436,931 Other investments 1,087,377 1,087,377 Investments in other ventures, under equity method 106,549 106,549 Total investments $ 17,368,789 $ 17,368,789

Schedule II. Condensed Financia

Schedule II. Condensed Financial Information Of Registrant	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Condensed Financial Information of Registrant	SCHEDULE II RENAISSANCERE HOLDINGS LTD. CONDENSED FINANCIAL INFORMATION OF REGISTRANT RENAISSANCERE HOLDINGS LTD. BALANCE SHEETS AT DECEMBER 31, 2019 AND 2018 (PARENT COMPANY) (THOUSANDS OF UNITED STATES DOLLARS) At December 31, 2019 2018 Assets Fixed maturity investments trading, at fair value - amortized cost $998 at December 31, 2019 (2018 - $238,989) $ 1,005 $ 240,443 Short term investments, at fair value 189,446 72,917 Cash and cash equivalents 26,460 3,534 Investments in subsidiaries 5,204,260 4,414,475 Due from subsidiaries 10,725 57,039 Accrued investment income — 1,046 Receivable for investments sold 173 203 Other assets 847,406 458,842 Goodwill and other intangible assets 116,212 120,476 Total assets $ 6,395,687 $ 5,368,975 Liabilities and Shareholders’ Equity Liabilities Notes and bank loans payable $ 391,475 $ 300,000 Due to subsidiaries 6,708 6,453 Other liabilities 26,137 17,442 Total liabilities 424,320 323,895 Shareholders’ Equity Preference shares: $1.00 par value – 16,010,000 shares issued and outstanding at December 31, 2019 (2018 – 16,010,000) 650,000 650,000 Common shares: $1.00 par value – 44,148,116 shares issued and outstanding at December 31, 2019 (2018 – 42,207,390) 44,148 42,207 Additional paid-in capital 568,277 296,099 Accumulated other comprehensive loss (1,939 ) (1,433 ) Retained earnings 4,710,881 4,058,207 Total shareholders’ equity 5,971,367 5,045,080 Total liabilities and shareholders’ equity $ 6,395,687 $ 5,368,975 SCHEDULE II RENAISSANCERE HOLDINGS LTD. CONDENSED FINANCIAL INFORMATION OF REGISTRANT – CONTINUED RENAISSANCERE HOLDINGS LTD. STATEMENTS OF OPERATIONS FOR THE YEARS ENDED DECEMBER 31, 2019 , 2018 AND 2017 (PARENT COMPANY) (THOUSANDS OF UNITED STATES DOLLARS) Year ended December 31, 2019 2018 2017 Revenues Net investment income $ 39,629 $ 24,791 $ 23,109 Net foreign exchange gains (losses) 7,342 (3 ) (1 ) Net realized and unrealized gains (losses) on investments 12,393 633 (1,357 ) Total revenues 59,364 25,421 21,751 Expenses Interest expense 18,086 5,683 1,572 Operational expenses 7,506 7,679 11,314 Corporate expenses 58,393 25,190 18,546 Total expenses 83,985 38,552 31,432 Loss before equity in net income (loss) of subsidiaries (24,621 ) (13,131 ) (9,681 ) Equity in net income (loss) of subsidiaries 773,419 240,495 (212,708 ) Net income (loss) 748,798 227,364 (222,389 ) Dividends on preference shares (36,756 ) (30,088 ) (22,381 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders $ 712,042 $ 197,276 $ (244,770 ) RENAISSANCERE HOLDINGS LTD. STATEMENTS OF COMPREHENSIVE INCOME (LOSS) FOR THE YEARS ENDED DECEMBER 31, 2019 , 2018 AND 2017 (PARENT COMPANY) (THOUSANDS OF UNITED STATES DOLLARS) Year ended December 31, 2019 2018 2017 Comprehensive income (loss) Net income (loss) $ 748,798 $ 227,364 $ (222,389 ) Change in net unrealized gains on investments, net of tax 2,173 (1,657 ) (909 ) Foreign currency translation adjustments, net of tax (2,679 ) — — Comprehensive income (loss) available (attributable) to RenaissanceRe $ 748,292 $ 225,707 $ (223,298 ) SCHEDULE II RENAISSANCERE HOLDINGS LTD. CONDENSED FINANCIAL INFORMATION OF REGISTRANT – CONTINUED RENAISSANCERE HOLDINGS LTD. STATEMENTS OF CASH FLOWS FOR THE YEARS ENDED DECEMBER 31, 2019 , 2018 AND 2017 (PARENT COMPANY) (THOUSANDS OF UNITED STATES DOLLARS) Year ended December 31, 2019 2018 2017 Cash flows used in operating activities: Net income (loss) $ 748,798 $ 227,364 $ (222,389 ) Less: equity in net (income) loss of subsidiaries (773,419 ) (240,495 ) 212,708 (24,621 ) (13,131 ) (9,681 ) Adjustments to reconcile net income (loss) to net cash used in operating activities Net realized and unrealized (gains) losses on investments (12,393 ) (633 ) 1,357 Other 34,153 30,951 29,442 Net cash used in operating activities (2,861 ) 17,187 21,118 Cash flows provided by (used in) investing activities: Proceeds from maturities and sales of fixed maturity investments trading 306,579 384,818 261,601 Purchases of fixed maturity investments trading (66,740 ) (520,935 ) (344,463 ) Net (purchases) sales of short term investments (116,499 ) 48,600 243,571 Dividends and return of capital from subsidiaries 1,400,944 672,098 478,496 Contributions to subsidiaries (1,165,607 ) (785,785 ) (669,672 ) Due to (from) subsidiary (625,924 ) (227,762 ) 294,419 Net cash provided by (used in) investing activities (267,247 ) (428,966 ) 263,952 Cash flows provided by (used in) financing activities: Dividends paid – RenaissanceRe common shares (59,368 ) (52,841 ) (51,370 ) Dividends paid – preference shares (36,756 ) (30,088 ) (22,381 ) Issuance of debt, net of expenses 396,411 — — RenaissanceRe common share repurchases — — (188,591 ) RenaissanceRe common share issuance — 250,000 — Issuance of preference shares, net of expenses — 241,448 — Taxes paid on withholding shares (7,253 ) (7,862 ) (15,139 ) Net cash provided by (used in) financing activities 293,034 400,657 (277,481 ) Net increase (decrease) in cash and cash equivalents 22,926 (11,122 ) 7,589 Cash and cash equivalents, beginning of year 3,534 14,656 7,067 Cash and cash equivalents, end of year $ 26,460 $ 3,534 $ 14,656

Schedule III. Supplementary Ins

Schedule III. Supplementary Insurance Information	12 Months Ended
	Dec. 31, 2019
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Abstract]
Supplementary Insurance Information	SCHEDULE III RENAISSANCERE HOLDINGS LTD. AND SUBSIDIARIES SUPPLEMENTARY INSURANCE INFORMATION (THOUSANDS OF UNITED STATES DOLLARS) December 31, 2019 Year ended December 31, 2019 Deferred Policy Acquisition Costs Future Policy Benefits, Losses, Claims and Loss Expenses Unearned Premiums Premium Revenue Net Investment Income Benefits, Claims, Losses and Settlement Expenses Amortization of Deferred Policy Acquisition Costs Other Operating Expenses Net Written Premiums Property $ 79,795 $ 4,073,850 $ 539,183 $ 1,627,494 $ — $ 965,424 $ 313,761 $ 139,015 $ 1,654,259 Casualty and Specialty 584,196 5,310,059 1,991,792 1,710,909 — 1,131,637 448,678 84,546 1,727,234 Other — 440 — — 423,833 (40 ) (207 ) (828 ) — Total $ 663,991 $ 9,384,349 $ 2,530,975 $ 3,338,403 $ 423,833 $ 2,097,021 $ 762,232 $ 222,733 $ 3,381,493 December 31, 2018 Year ended December 31, 2018 Deferred Future Policy Unearned Premium Net Benefits, Amortization Other Net Written Property $ 66,656 $ 3,086,254 $ 379,943 $ 1,050,831 $ — $ 497,895 $ 177,912 $ 112,954 $ 1,055,188 Casualty and Specialty 410,005 2,985,393 1,336,078 925,298 — 622,320 255,079 64,883 1,076,714 Other — 4,624 — — 261,866 (197 ) (2 ) 430 — Total $ 476,661 $ 6,076,271 $ 1,716,021 $ 1,976,129 $ 261,866 $ 1,120,018 $ 432,989 $ 178,267 $ 2,131,902 December 31, 2017 Year ended December 31, 2017 Deferred Future Policy Unearned Premium Net Benefits, Amortization Other Net Written Property $ 63,583 $ 2,486,390 $ 347,032 $ 931,070 $ — $ 1,297,985 $ 113,816 $ 94,194 $ 978,014 Casualty and Specialty 362,968 2,575,492 1,130,577 786,501 — 565,026 233,077 66,548 893,307 Other — 18,526 — 4 222,209 (1,583 ) (1 ) 36 4 Total $ 426,551 $ 5,080,408 $ 1,477,609 $ 1,717,575 $ 222,209 $ 1,861,428 $ 346,892 $ 160,778 $ 1,871,325

Schedule IV. Supplemental Sched

Schedule IV. Supplemental Schedule of Reinsurance Premiums	12 Months Ended
	Dec. 31, 2019
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]
Supplemental Schedule of Reinsurance Premiums	SCHEDULE IV RENAISSANCERE HOLDINGS LTD. AND SUBSIDIARIES SUPPLEMENTAL SCHEDULE OF REINSURANCE PREMIUMS (THOUSANDS OF UNITED STATES DOLLARS) Gross Amounts Ceded to Other Companies Assumed From Other Companies Net Amount Percentage of Amount Assumed to Net Year ended December 31, 2019 Property and liability premiums earned $ 404,525 $ 1,414,383 $ 4,348,261 $ 3,338,403 130 % Year ended December 31, 2018 Property and liability premiums earned $ 292,219 $ 1,095,886 $ 2,779,796 $ 1,976,129 141 % Year ended December 31, 2017 Property and liability premiums earned $ 244,285 $ 833,929 $ 2,307,219 $ 1,717,575 134 %

Schedule VI. Supplementary Insu

Schedule VI. Supplementary Insurance Information Concerning Property-Casualty Insurance Operations	12 Months Ended
	Dec. 31, 2019
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Abstract]
Supplemental Insurance Information Concerning Property-Casualty Insurance Operations	SCHEDULE VI RENAISSANCERE HOLDINGS LTD. AND SUBSIDIARIES SUPPLEMENTARY INSURANCE INFORMATION CONCERNING PROPERTY-CASUALTY INSURANCE OPERATIONS (THOUSANDS OF UNITED STATES DOLLARS) Affiliation with Registrant Deferred Policy Acquisition Costs Reserves for Unpaid Claims and Claim Adjustment Expenses Discount, if any, Deducted Unearned Premiums Earned Premiums Net Investment Income Consolidated Subsidiaries Year ended December 31, 2019 $ 663,991 $ 9,384,349 $ — $ 2,530,975 $ 3,338,403 $ 423,833 Year ended December 31, 2018 $ 476,661 $ 6,076,271 $ — $ 1,716,021 $ 1,976,129 $ 261,866 Year ended December 31, 2017 $ 426,551 $ 5,080,408 $ — $ 1,477,609 $ 1,717,575 $ 222,209 Claims and Claim Adjustment Expenses Incurred Related to Amortization of Deferred Policy Acquisition Costs Paid Claims and Claim Adjustment Expenses Net Premiums Written Affiliation with Registrant Current Year Prior Year Consolidated Subsidiaries Year ended December 31, 2019 $ 2,123,876 $ (26,855 ) $ 762,232 $ 1,098,054 $ 3,381,493 Year ended December 31, 2018 $ 1,390,767 $ (270,749 ) $ 432,989 $ 894,769 $ 2,131,902 Year ended December 31, 2017 $ 1,902,424 $ (40,996 ) $ 346,892 $ 974,825 $ 1,871,325

Significant Accounting Polici_2

Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	BASIS OF PRESENTATION These consolidated financial statements have been prepared on the basis of accounting principles generally accepted in the United States (“GAAP”). All significant intercompany accounts and transactions have been eliminated from these statements. Certain comparative information has been reclassified to conform to the current presentation.
Use of Estimates in Financial Statements	USE OF ESTIMATES IN FINANCIAL STATEMENTS The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported and disclosed amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates. The major estimates reflected in the Company’s consolidated financial statements include, but are not limited to, the reserve for claims and claim expenses; reinsurance recoverables, including allowances for reinsurance recoverables deemed uncollectible; estimates of written and earned premiums; fair value, including the fair value of investments, financial instruments and derivatives; impairment charges; deferred acquisition costs and the value of business acquired (“VOBA”) and the Company’s deferred tax valuation allowance.
Premiums and Related Expenses	PREMIUMS AND RELATED EXPENSES Premiums are recognized as income, net of any applicable reinsurance or retrocessional coverage purchased, over the terms of the related contracts and policies. Premiums written are based on contract and policy terms and include estimates based on information received from both insureds and ceding companies. Subsequent differences arising on such estimates are recorded in the period in which they are determined. Unearned premiums represent the portion of premiums written that relate to the unexpired terms of contracts and policies in force. Amounts are computed by pro rata methods based on statistical data or reports received from ceding companies. Reinstatement premiums are estimated after the occurrence of a significant loss and are recorded in accordance with the contract terms based upon paid losses and case reserves. Reinstatement premiums are earned when written. Acquisition costs are incurred when a contract or policy is issued and only the costs directly related to the successful acquisition of new and renewal contract or policies are deferred and amortized over the same period in which the related premiums are earned. Acquisition costs consist principally of commissions, brokerage and premium tax expenses. Certain of our assumed contracts contain profit sharing provisions or adjustable commissions that are estimated based on the expected loss and loss adjustment expense on those contracts. Acquisition costs include accruals for such estimates of commissions and are shown net of commissions and profit commissions earned on ceded reinsurance. Deferred policy acquisition costs are limited to their estimated realizable value based on the related unearned premiums. Anticipated claims and claim expenses, based on historical and current experience, and anticipated investment income related to those premiums are considered in determining the recoverability of deferred acquisition costs.
Claims and Claim Expenses	CLAIMS AND CLAIM EXPENSES The reserve for claims and claim expenses includes estimates for unpaid claims and claim expenses on reported losses as well as an estimate of losses incurred but not reported. The reserve is based on individual claims, case reserves and other reserve estimates reported by insureds and ceding companies as well as management estimates of ultimate losses. Inherent in the estimates of ultimate losses are expected trends in claim severity and frequency and other factors which could vary significantly as claims are settled. Also, during the past few years, the Company has increased its casualty and specialty reinsurance businesses, but does not have the benefit of a significant amount of its own historical experience in certain of these lines of business. Accordingly, the reserving for incurred losses in these lines of business could be subject to greater variability. Ultimate losses may vary materially from the amounts provided in the consolidated financial statements. These estimates are reviewed regularly and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments, if any, are reflected in the consolidated statements of operations in the period in which they become known and are accounted for as changes in estimates.
Reinsurance	REINSURANCE Amounts recoverable from reinsurers are estimated in a manner consistent with the claim liability associated with the reinsured policies. For multi-year retrospectively rated contracts, the Company accrues amounts (either assets or liabilities) that are due to or from assuming companies based on estimated contract experience. If the Company determines that adjustments to earlier estimates are appropriate, such adjustments are recorded in the period in which they are determined. Reinsurance recoverables on dual trigger reinsurance contracts require the Company to estimate its ultimate losses applicable to these contracts as well as estimate the ultimate amount of insured industry losses that will be reported by the applicable statistical reporting agency, as per the contract terms. Amounts recoverable from reinsurers are recorded net of a valuation allowance for estimated uncollectible recoveries. Assumed and ceded reinsurance contracts that lack a significant transfer of risk are treated as deposits. Certain assumed and ceded reinsurance contracts that do not meet all of the criteria to be accounted for as reinsurance in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic Financial Services - Insurance have been accounted for at fair value under the fair value option in accordance with FASB ASC Topic Financial Instruments.
Fixed Maturity Investments, Short Term Investments and Equity Investments, Classified as Trading	INVESTMENTS, CASH AND CASH EQUIVALENTS Fixed Maturity Investments Investments in fixed maturities are classified as trading and are reported at fair value. Investment transactions are recorded on the trade date with balances pending settlement reflected in the balance sheet as a receivable for investments sold or a payable for investments purchased. Net investment income includes interest and dividend income together with amortization of market premiums and discounts and is net of investment management and custody fees. The amortization of premium and accretion of discount for fixed maturity securities is computed using the effective yield method. For mortgage-backed securities and other holdings for which there is prepayment risk, prepayment assumptions are evaluated quarterly and revised as necessary. Any adjustments required due to the change in effective yields and maturities are recognized on a prospective basis through yield adjustments. Fair values of investments are based on quoted market prices, or when such prices are not available, by reference to broker or underwriter bid indications and/or internal pricing valuation techniques. The net unrealized appreciation or depreciation on fixed maturity investments trading is included in net realized and unrealized gains (losses) on investments in the consolidated statements of operations. Realized gains or losses on the sale of investments are determined on the basis of the first in first out cost method. Short Term Investments Short term investments, which are managed as part of the Company’s investment portfolio and have a maturity of one year or less when purchased, are carried at fair value. The net unrealized appreciation or depreciation on short term investments is included in net realized and unrealized gains on investments in the consolidated statements of operations. Equity Investments, Classified as Trading Equity investments are accounted for at fair value in accordance with FASB ASC Topic Financial Instruments. Fair values are primarily priced by pricing services, reflecting the closing price quoted for the final trading day of the period. Net investment income includes dividend income and the net realized and unrealized appreciation or depreciation on equity investments is included in net realized and unrealized gains (losses) on investments in the consolidated statements of operations.
Other Investments	Other Investments The Company accounts for its other investments at fair value in accordance with FASB ASC Topic Financial Instruments with interest, dividend income, income distributions and realized and unrealized gains and losses included in net investment income. The fair value of certain of the Company’s fund investments, which principally include private equity investments, senior secured bank loan funds and hedge funds, is recorded on its balance sheet in other investments, and is generally established on the basis of the net valuation criteria established by the managers of such investments, if applicable. The net valuation criteria established by the managers of such investments is established in accordance with the governing documents of such investments. Certain of the Company’s fund managers, fund administrators, or both, are unable to provide final fund valuations as of the Company’s current reporting date. The typical reporting lag experienced by the Company to receive a final net asset value report is one month for hedge funds and senior secured bank loan funds and three months for private equity investments, although, in the past, in respect of certain of the Company’s private equity investments, the Company has on occasion experienced delays of up to six months at year end, as the private equity investments typically complete their respective year-end audits before releasing their final net asset value statements. In circumstances where there is a reporting lag between the current period end reporting date and the reporting date of the latest fund valuation, the Company estimates the fair value of these funds by starting with the prior month or quarter-end fund valuations, adjusting these valuations for actual capital calls, redemptions or distributions, as well as the impact of changes in foreign currency exchange rates, and then estimating the return for the current period. In circumstances in which the Company estimates the return for the current period, all information available to the Company is utilized. This principally includes preliminary estimates reported to the Company by its fund managers, obtaining the valuation of underlying portfolio investments where such underlying investments are publicly traded and therefore have a readily observable price, using information that is available to the Company with respect to the underlying investments, reviewing various indices for similar investments or asset classes, as well as estimating returns based on the results of similar types of investments for which the Company has obtained reported results, or other valuation methods, where possible. Actual final fund valuations may differ, perhaps materially so, from the Company’s estimates and these differences are recorded in the Company’s statement of operations in the period in which they are reported to the Company as a change in estimate. The Company’s other investments also include investments in catastrophe bonds which are recorded at fair value and the fair value is based on broker or underwriter bid indications.
Investments in Other Ventures, Under Equity Method	Investments in Other Ventures, Under Equity Method Investments in which the Company has significant influence over the operating and financial policies of the investee are classified as investments in other ventures, under equity method, and are accounted for under the equity method of accounting. Under this method, the Company records its proportionate share of income or loss from such investments in its results for the period. Any decline in value of investments in other ventures, under equity method considered by management to be other-than-temporary is charged to income in the period in which it is determined.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents include money market instruments with a maturity of ninety days or less when purchased.
Stock Incentive Compensation	STOCK INCENTIVE COMPENSATION The Company is authorized to issue restricted stock awards and units, performance shares, stock options and other equity-based awards to its employees and directors. The fair value of the compensation cost is measured at the grant date and expensed over the period for which the employee is required to provide services in exchange for the award. In addition, the Company is authorized to issue cash settled restricted stock units (“CSRSU”) to its employees. The fair value of CSRSUs is determined using the fair market value of RenaissanceRe common shares at the end of each reporting period and is expensed over the period for which the employee is required to provide service in exchange for the award. The fair value of these awards is recorded on the Company’s consolidated balance sheet as a liability as it is expensed and until the point payment is made to the employee. The Company has elected to recognize forfeitures as they occur rather than estimating service-based forfeitures over the requisite service period.
Derivatives	DERIVATIVES From time to time, the Company enters into derivative instruments such as futures, options, swaps, forward contracts and other derivative contracts primarily to manage its foreign currency exposure, obtain exposure to a particular financial market, for yield enhancement, or for trading and to assume risk. The Company accounts for its derivatives in accordance with FASB ASC Topic Derivatives and Hedging , which requires all derivatives to be recorded at fair value on the Company’s balance sheet as either assets or liabilities, depending on their rights or obligations, with changes in fair value reflected in current earnings. Commencing in 2019, the Company elected to adopt hedge accounting for certain of its derivative instruments used as hedges of a net investment in a foreign operation, as discussed below. The fair value of the Company’s derivatives is estimated by reference to quoted prices or broker quotes, where available, or in the absence of quoted prices or broker quotes, the use of industry or internal valuation models. Hedges of the Net Investment in a Foreign Operation Changes in the fair value of derivative instruments used to hedge the net investment in a foreign operation, to the extent effective as a hedge, are recorded as a component of accumulated other comprehensive income (loss) in foreign currency translation adjustments, net of tax. Cumulative changes in fair value recorded in accumulated other comprehensive income (loss) are reclassified into earnings upon the sale, or complete or substantially complete liquidation, of the foreign operation. Any hedge ineffectiveness is recorded immediately in current period earnings as net foreign exchange gains (losses). Hedge Documentation and Effectiveness Testing To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in value or cash flow of the hedged item. At the inception of a hedge, the Company formally documents relationships between hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking each hedge transaction. The documentation process includes linking derivatives that are designated as net investment hedges to specific assets or liabilities on the consolidated balance sheet. The Company also formally assesses, both at the hedge's inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in the net investment in a foreign operation. The Company will discontinue hedge accounting prospectively if it determines that the derivative is no longer highly effective in offsetting changes in the net investment in a foreign operation, the derivative is no longer designated as a hedging instrument, or the derivative expires or is sold, terminated or exercised. If hedge accounting is discontinued, the derivative continues to be carried at fair value on the consolidated balance sheet with changes in its fair value recognized in current period earnings through net realized and unrealized gains (losses) on investments.
Fair Value	FAIR VALUE The Company accounts for certain of its assets and liabilities at fair value in accordance with FASB ASC Topic Fair Value Measurement s and Disclosures . The Company recognizes the change in unrealized gains and losses arising from changes in fair value in its statements of operations. The use of fair value to measure certain assets and liabilities with resulting unrealized gains or losses is pervasive within the Company’s consolidated financial statements. Fair value is defined under accounting guidance currently applicable to the Company to be the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between open market participants at the measurement date. The Company recognizes the change in unrealized gains and losses arising from changes in fair value in its consolidated statements of operations. FASB ASC Topic Fair Value Measurements and Disclosures prescribes a fair value hierarchy that prioritizes the inputs to the respective valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to valuation techniques that use at least one significant input that is unobservable (Level 3). The three levels of the fair value hierarchy are described below: • Fair values determined by Level 1 inputs utilize unadjusted quoted prices obtained from active markets for identical assets or liabilities for which the Company has access. The fair value is determined by multiplying the quoted price by the quantity held by the Company; • Fair values determined by Level 2 inputs utilize inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets and liabilities in active markets, and inputs other than quoted prices that are observable for the asset or liability, such as interest rates and yield curves that are observable at commonly quoted intervals, broker quotes and certain pricing indices; and • Level 3 inputs are based all or in part on significant unobservable inputs for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. In these cases, significant management assumptions can be used to establish management’s best estimate of the assumptions used by other market participants in determining the fair value of the asset or liability. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, the level in the fair value hierarchy within which the fair value measurement in its entirety falls has been determined based on the lowest level input that is significant to the fair value measurement of the asset or liability. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and the Company considers factors specific to the asset or liability. In order to determine if a market is active or inactive for a security, the Company considers a number of factors, including, but not limited to, the spread between what a seller is asking for a security and what a buyer is bidding for the same security, the volume of trading activity for the security in question, the price of the security compared to its par value (for fixed maturity investments), and other factors that may be indicative of market activity. There have been no material changes in the Company’s valuation techniques, nor have there been any transfers between Level 1 and Level 2, or Level 2 and Level 3 during the period represented by these consolidated financial statements.
Business Combinations	The Company initially recorded VOBA to reflect the establishment of the value of business acquired asset, which represents the estimated present value of the expected underwriting profit within the unearned premiums liability, net of reinsurance, less costs to service the related policies and a risk premium. VOBA is derived using, among other things, estimated loss ratios by line of business to calculate the underwriting profit, weighted average cost of capital, risk premium and expected payout patterns. The adjustment for VOBA will be amortized to acquisition expenses over approximately two years , as the contracts for business in-force as of the acquisition date expire. The Company accounts for business combinations in accordance with FASB ASC Topic Business Combinations , and goodwill and other intangible assets that arise from business combinations in accordance with FASB ASC Topic Intangibles – Goodwill and Other
Goodwill and Other Intangible Assets	A purchase price that is in excess of the fair value of the net assets acquired arising from a business combination is recorded as goodwill, and is not amortized. Other intangible assets with a finite life are amortized over the estimated useful life of the asset. Other intangible assets with an indefinite useful life are not amortized. Goodwill and other indefinite life intangible assets are tested for impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying amount may not be recoverable. Finite life intangible assets are reviewed for indicators of impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying amount may not be recoverable, and tested for impairment if appropriate. For purposes of the annual impairment evaluation, goodwill is assigned to the applicable reporting unit of the acquired entities giving rise to the goodwill. Goodwill and other intangible assets recorded in connection with investments accounted for under the equity method, are recorded as “Investments in other ventures, under equity method” on the Company’s consolidated balance sheets. The Company has established the beginning of the fourth quarter as the date for performing its annual impairment tests. The Company has the option to first assess qualitative factors to determine whether it is necessary to perform the quantitative goodwill impairment test. Under this option, the Company would not be required to calculate the fair value of a reporting unit unless the Company determines, based on its qualitative assessment, that it is more likely than not that a reporting unit’s fair value is less than its carrying amount. If goodwill or other intangible assets are impaired, they are written down to their estimated fair value with a corresponding expense reflected in the Company’s consolidated statements of operations.
Noncontrolling Interests	NONCONTROLLING INTERESTS The Company accounts for redeemable noncontrolling interests in the mezzanine section of the Company’s consolidated balance sheet in accordance with United States Securities and Exchange Commission (“SEC”) guidance which is applicable to SEC registrants. The SEC guidance requires shares, not required to be accounted for in accordance with FASB ASC Topic Distinguishing Liabilities from Equity , and having redemption features that are not solely within the control of the issuer, to be classified outside of permanent equity in the mezzanine section of the balance sheet. Because the share classes related to the redeemable noncontrolling interest portion of the issuer are not considered liabilities in accordance with FASB ASC Topic Distinguishing Liabilities from Equity and have redemption features that are not solely within the control of the issuer, the redeemable noncontrolling interests are presented in the mezzanine section on the Company’s consolidated balance sheet in accordance with the SEC guidance noted above. The SEC guidance does not impact the accounting for redeemable noncontrolling interest on the consolidated statements of operations; therefore, the provisions of FASB ASC Topic Consolidation with respect to the consolidated statements of operations still apply, and net income attributable to redeemable noncontrolling interests is presented separately in the Company’s consolidated statements of operations.
Variable Interest Entities	VARIABLE INTEREST ENTITIES The Company accounts for VIEs in accordance with FASB ASC Topic Consolidation , which requires the consolidation of all VIEs by the primary beneficiary, that being the investor that has the power to direct the activities of the VIE and that will absorb a portion of the VIE’s expected losses or residual returns that could potentially be significant to the VIE. For VIEs the Company determines it has a variable interest in, it determines whether it is the primary beneficiary of a VIE by performing an analysis that principally considers: (i) the VIE’s purpose and design, including the risks the VIE was designed to create and pass through to its variable interest holders; (ii) the VIE’s capital structure; (iii) the terms between the VIE and its variable interest holders and other parties involved with the VIE; (iv) which variable interest holders have the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance; (v) which variable interest holders have the obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE; and (vi) related party relationships. The Company reassesses its initial determination of whether the Company is the primary beneficiary of a VIE upon changes in facts and circumstances that could potentially alter the Company’s assessment.
Earnings Per Share	EARNINGS PER SHARE The Company calculates earnings per share in accordance with FASB ASC Topic Earnings per Share. Basic earnings per share are based on weighted average common shares and exclude any dilutive effects of options and restricted stock. Diluted earnings per share assumes the exercise of all dilutive stock options and restricted stock grants. The two-class method is used to determine earnings per share based on dividends declared on common shares and participating securities (i.e., distributed earnings) and participation rights of participating securities in any undistributed earnings. Each unvested restricted share granted by the Company to its employees is considered a participating security and the Company uses the two-class method to calculate its net income available to RenaissanceRe common shareholders per common share – basic and diluted.
Foreign Exchange	FOREIGN EXCHANGE Monetary assets and liabilities denominated in a currency other than the functional currency of the Company’s subsidiaries in which those monetary assets and liabilities reside are revalued into such subsidiary’s functional currency at the prevailing exchange rate on the balance sheet date. Revenues and expenses denominated in a currency other than the functional currency of the Company’s subsidiaries, are valued at the exchange rate on the date on which the underlying revenue or expense transaction occurred. The net effect of these revaluation adjustments are recognized in the Company’s consolidated statement of operations as part of net foreign exchange (gains) losses. The Company’s functional currency is the U.S. dollar. Certain of the Company’s subsidiaries have a functional currency other than the U.S. dollar. Assets and liabilities of foreign operations whose functional currency is not the U.S. dollar are translated into the Company's U.S. dollar reporting currency at prevailing balance sheet-date exchange rates, while revenue and expenses of such foreign operations are translated into the Company's U.S. dollar functional currency at monthly average exchange rates during the year. The net effect of these translation adjustments, as well as any gains or losses on intercompany balances for which settlement is not planned or anticipated in the foreseeable future, net of applicable deferred income taxes, is included in the Company’s consolidated balance sheet as currency translation adjustments and reflected within accumulated other comprehensive income (loss).
Taxation	TAXATION Income taxes have been provided for in accordance with the provisions of FASB ASC Topic Income Taxes . Deferred tax assets and liabilities result from temporary differences between the amounts recorded in the consolidated financial statements and the tax basis of the Company’s assets and liabilities. Such temporary differences are primarily due to net operating loss carryforwards and GAAP versus tax basis accounting differences relating to interest expense, underwriting results, accrued expenses and investments. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance against deferred tax assets is recorded if it is more likely than not that all, or some portion, of the benefits related to deferred tax assets will not be realized.
Taxation, Uncertainties	Uncertain tax positions are also accounted for in accordance with FASB ASC Topic Income Taxes . Uncertain tax positions must meet a more likely than not recognition threshold to be recognized.
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements Not Yet Adopted	RECENTLY ADOPTED ACCOUNTING PRONOUNCEMENTS Leases In February 2016, the FASB issued Accounting Standards Update (“ASU”) No. 2016-02, Leases and subsequently issued a number of other ASUs to amend the guidance, each ultimately reflected in FASB ASC Topic Leases . FASB ASC Topic Leases requires, among other items, lessees to recognize lease assets and lease liabilities on the balance sheet for those leases classified as operating leases under the previous guidance. FASB ASC Topic Leases was effective for public business entities for annual and interim periods beginning after December 15, 2018. The Company has adopted FASB ASC Topic Leases through the application of the modified retrospective transition approach. In addition, the Company employed certain practical expedients permitted under the guidance and utilized its incremental borrowing rate in determining the present value of lease payments, not yet paid. The adoption of this guidance did not have a material impact on the Company’s consolidated statements of operations and financial position. The Company determined there was no material impact and as a result, there was no cumulative effect adjustment to opening retained earnings as of January 1, 2019. Intra-Entity Transfers of Assets Other Than Inventory In October 2016, the FASB issued ASU No. 2016-16, Intra-Entity Transfers of Assets Other Than Inventory (“ASU 2016-16”). ASU 2016-16 requires entities to recognize the income tax consequences of intra-entity transfers of assets other than inventory when the transfers occur; this is a change from current guidance which prohibits the recognition of current and deferred income taxes until the underlying assets have been sold to outside entities. ASU 2016-16 was effective for public business entities for annual and interim periods beginning after December 15, 2018. The adoption of this guidance did not have a material impact on the Company’s consolidated statements of operations and financial position. Improvements to Employee Share-Based Payment Accounting In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”). ASU 2016-09 was issued to simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, treatment of forfeitures, classification of awards as either equity or liabilities, and the classification of taxes paid on the statements of cash flows. ASU 2016-09 became effective for the Company in annual and interim periods beginning after December 15, 2016. The cumulative effect of the adoption of ASU 2016-09 was a $2.2 million increase to opening retained earnings as of January 1, 2017. Revenue from Contracts with Customers In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). ASU 2014-09 provides comprehensive guidance on the recognition of revenue from customers arising from the transfer of goods and services. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 also provides guidance on accounting for certain contract costs and had also required new disclosures. ASU 2014-09 was to be effective for public business entities in annual and interim periods beginning after December 15, 2016, however in July 2015, the FASB decided to defer by one year the effective dates of ASU 2014-09, and as a result, ASU 2014-09 is effective for public business entities in annual and interim periods beginning after December 15, 2017. ASU 2014-09 notably excludes the accounting for insurance contracts, leases, financial instruments and guarantees. As a result, the Company’s implementation efforts primarily focused on other income and operational expenses on its consolidated statements of operations. The adoption of ASU 2014-09 did not have a material impact on the Company’s consolidated statements of operations and financial position. Recognition and Measurement of Financial Assets and Financial Liabilities In January 2016, the FASB issued ASU No. 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU 2016-01”). ASU 2016-01 requires equity investments (except those accounted for under the equity method of accounting or those that result in the consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income, simplifies the impairment assessment of equity investments without readily determinable values by requiring a qualitative assessment to identify impairment, eliminates the requirement to disclose the methods and significant assumptions used to estimate the fair value for financial instruments measured at amortized cost, requires the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes, requires separate presentation in other comprehensive income of the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the organization has elected to measure the liabilities in accordance with the fair value option, requires the separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the accompanying notes to the financial statements and clarifies that the reporting organization should evaluate the need for a valuation allowance on a deferred tax asset related to available for sale securities in combination with the organization’s other deferred tax assets. ASU 2016-01 is effective for public business entities in annual and interim periods beginning after December 15, 2017. The adoption of ASU 2016-01 did not have a material impact on the Company’s consolidated statements of operations and financial position. Classification of Certain Cash Receipts and Cash Payments In August 2016, the FASB issued ASU No. 2016-15, Classification of Certain Cash Receipts and Cash Payments (“ASU 2016-15”). ASU 2016-15 clarifies the classification of receipts and payments in the statement of cash flows. ASU 2016-15 provides guidance related to (1) settlement and payment of zero coupon debt instruments, (2) contingent consideration, (3) proceeds from settlement of insurance claims, (4) proceeds from settlement of corporate and bank owned life insurance policies, (5) distributions from equity method investees, (6) cash receipts from beneficial interests obtained by a transferor, and (7) general guidelines for cash receipts and payments that have more than one aspect of classification. ASU 2016-15 is effective for public business entities for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The adoption of ASU 2016-15 resulted in the reclassification of $20.0 million of cash inflows from cash flows provided by operating activities, to cash flows used in investing activities for 2017. This amount related to a return of investment associated with the Company’s investment in Top Layer Reinsurance Ltd, recorded under the equity method of accounting. RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS NOT YET ADOPTED Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 modifies the recognition of credit losses by replacing the incurred loss impairment methodology with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. ASU 2016-13 is applicable to financial assets such as loans, debt securities, trade receivables, off-balance sheet credit exposures, reinsurance receivables, and other financial assets that have the contractual right to receive cash. The measurement of expected credit losses is based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. The Company's invested assets are measured at fair value through net income, and therefore those invested assets would not be impacted by the adoption of ASU 2016-13. The Company has other financial assets, such as reinsurance recoverables, that could be impacted by the adoption of ASU 2016-13. ASU 2016-13 is effective for public business entities that are SEC filers for annual and interim periods beginning after December 15, 2019. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company’s consolidated statements of operations and financial position. Simplifying the Test for Goodwill Impairment In January 2017, the FASB issued ASU No. 2017-04, Simplifying the Test for Goodwill Impairment (“ASU 2017-04”). Among other things, ASU 2017-04 requires the following: (1) the elimination of step two of the goodwill impairment test; entities will no longer utilize the implied fair value of their assets and liabilities for purposes of testing goodwill for impairment, (2) the quantitative portion of the goodwill impairment test will be performed by comparing the fair value of a reporting unit with its carrying amount; an impairment charge is to be recognized for the excess of carrying amount over fair value, but only to the extent of the amount of goodwill allocated to that reporting unit, and (3) foreign currency translation adjustments are not to be allocated to a reporting unit from an entity’s accumulated other comprehensive income (loss); the reporting unit’s carrying amount should include only the currently translated balances of the assets and liabilities assigned to the reporting unit. ASU 2017-04 is effective for public business entities that are SEC filers for annual periods, or any interim goodwill impairment tests in annual periods, beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company’s consolidated statements of operations and financial position. Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued ASU No. 2018-13, Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement (“ASU 2018-13”). The ASU 2018-13 modifies the disclosure requirements of fair value measurements as part of the disclosure framework project with the objective to improve the effectiveness of disclosures in the notes to the financial statements. ASU 2018-13 allows for removal of the amount and reasons for transfer between Level 1 and Level 2 of the fair value hierarchy; the policy for transfers between levels; and the valuation processes for Level 3 fair value measurements. ASU 2018-13 is effective for all entities for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company’s consolidated statements of operations and financial position.

Acquisition of Tokio Millenni_2

Acquisition of Tokio Millennium Re (Tables)	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Schedule of Acquisition Purchase Price and Financial Results	The Company's total purchase price for TMR was calculated as follows: Special Dividend Special Dividend paid to common shareholders of Tokio and holders of Tokio equity awards $ 500,000 RenaissanceRe common shares Common shares issued by RenaissanceRe to Tokio 1,739,071 Common share price of RenaissanceRe (1) $ 143.75 Market value of RenaissanceRe common shares issued by RenaissanceRe to Tokio 249,998 Cash consideration Cash consideration paid by RenaissanceRe as acquisition consideration 813,595 Total purchase price 1,563,593 Less: Special Dividend paid to Tokio (500,000 ) Net purchase price $ 1,063,593 (1) RenaissanceRe common share price was based on the 30 -day trailing volume weighted average price of $143.7539 as of market close on March 15, 2019, which approximates fair value. The following table summarizes the net contribution from the acquisition of TMR since March 22, 2019 that has been included in the Company's consolidated statements of operations and comprehensive income for the year ended December 31, 2019 . Operating activities of TMR from the acquisition date, March 22, 2019, through December 31, 2019 are included in the Company’s consolidated statements of operations for the year ended December 31, 2019 . The unaudited net contribution of the acquisition and integration of TMR is provided for informational purposes only and is not necessarily, and should not be assumed to be, an indication of the results that may be achieved in the future. These results are not used as a part of management analysis of the financial performance of the Company’s business. These results primarily reflect items recorded directly by TMR, including: 1) net earned premium and net underwriting income on the in-force portfolio acquired with the acquisition of TMR and currently retained on TMR entities’ balance sheets; 2) net earned premium and net underwriting income for those contracts which have renewed post-acquisition on one of the acquired TMR entities’ balance sheets; 3) net investment income and net realized and unrealized gains recorded directly by TMR; and 4) certain direct costs incurred directly by TMR. In addition, these results, where possible, are adjusted for transaction and integration related costs incurred by the Company. However, these results do not reflect on-going operating costs incurred by the Company in supporting TMR unless such costs are incurred directly by TMR. These results also do not give consideration to the impact of possible revenue enhancements, expense efficiencies, synergies or asset dispositions that may be achieved in the future. These results involve significant estimates and are not indicative of the future results of the acquired TMR entities which will be further impacted by potential changes in targeted business mix, investment management strategies, and synergies recognized from changes in the combined entity’s operating structure, as well as the impact of changes in other business and capital management strategies. Since the acquisition date, a growing number of underlying policies have been underwritten onto different legal entities, staffing has been allocated to new activities, and reinsurance has been purchased to cover combined risks, only some of which would have been reflected in the underlying legacy TMR results. In future quarters, the summary results of TMR will become increasingly impracticable to produce, and even less indicative of the results of the acquired TMR entities, given the significant estimates involved and the nature and pace of our integration activities, which are intended to integrate TMR as quickly as possible. Year ended December 31, 2019 (1) Total revenues $ 922,727 Net income available to RenaissanceRe common shareholders (2) $ 99,169 (1) Includes the net contribution from the acquisition of TMR since March 22, 2019 that has been included in the Company’s consolidated statements of operations and comprehensive income through December 31, 2019 . (2) Includes $49.7 million of corporate expenses associated with the acquisition and integration of TMR for the year ended December 31, 2019 .
Schedule of Fair Value of Net Assets Acquired and Liabilities Assumed	The purchase price was allocated to the acquired assets and liabilities of the Company based on estimated fair values on March 22, 2019, the date the transaction closed, as detailed below. During the quarter ended March 31, 2019, the Company recognized goodwill of $13.1 million , based on foreign exchange rates on March 22, 2019, attributable to the excess of the purchase price over the fair value of the net assets of TMR. The Company recognized identifiable finite lived intangible assets of $11.2 million , which will be amortized over a weighted average period of 10.5 years , identifiable indefinite lived intangible assets of $6.8 million , and certain other adjustments to the fair values of the assets acquired, liabilities assumed and shareholders’ equity of TMR at March 22, 2019, based on foreign exchange rates on March 22, 2019, as summarized in the table below: Shareholders’ equity of TMR at March 22, 2019 $ 1,032,961 Adjustments for fair value, by applicable balance sheet caption: Net deferred acquisition costs and value of business acquired (56,788 ) Net reserve for claims and claim expenses 67,782 Goodwill and intangible assets at March 22, 2019 of TMR (6,569 ) Total adjustments for fair value by applicable balance sheet caption before tax impact 4,425 Other assets - net deferred tax liability related to fair value adjustments and value of business acquired (2,606 ) Total adjustments for fair value by applicable balance sheet caption, net of tax 1,819 Adjustments for fair value of the identifiable intangible assets: Identifiable indefinite lived intangible assets (insurance licenses) 6,800 Identifiable finite lived intangible assets (top broker relationships and renewal rights) 11,200 Identifiable intangible assets before tax impact 18,000 Other assets - deferred tax liability on identifiable intangible assets (2,281 ) Total adjustments for fair value of the identifiable intangible assets and value of business acquired, net of tax 15,719 Total adjustments for fair value by applicable balance sheet caption, identifiable intangible assets and value of business acquired, net of tax 17,538 Shareholders’ equity of TMR at fair value 1,050,499 Total net purchase price paid by RenaissanceRe 1,063,593 Excess purchase price over the fair value of net assets acquired assigned to goodwill $ 13,094
Schedule of Identifiable Intangible Assets Acquired	Identifiable intangible assets and accumulated amortization at December 31, 2019 , consisted of the following, based on foreign exchange rates on March 22, 2019, and are included in goodwill and other intangible assets on the Company’s consolidated balance sheet: Amount Economic Useful Life Top broker relationships $ 10,000 10.0 years Renewal rights 1,200 15.0 years Insurance licenses 6,800 Indefinite Gross identifiable intangible assets related to the acquisition of TMR, at March 22, 2019 18,000 Accumulated amortization (from March 22, 2019 through December 31, 2019) 810 Net identifiable intangible assets related to the acquisition of TMR at December 31, 2019 $ 17,190
Schedule of Pro Forma Information	The following table presents unaudited pro forma consolidated financial information for the years ended December 31, 2019 and 2018 , respectively, and assumes the acquisition of TMR occurred on January 1, 2018. The unaudited pro forma consolidated financial information is provided for informational purposes only and is not necessarily, and should not be assumed to be, an indication of the results that would have been achieved had the transaction been completed as of January 1, 2018 or that may be achieved in the future. The unaudited pro forma consolidated financial information does not give consideration to the impact of possible revenue enhancements, expense efficiencies, synergies or asset dispositions that may result from the acquisition of TMR. In addition, unaudited pro forma consolidated financial information does not include the effects of costs associated with any restructuring or integration activities resulting from the acquisition of TMR, as they are nonrecurring. Year ended December 31, 2019 2018 Total revenues $ 4,542,979 $ 3,338,903 Net income available to RenaissanceRe common shareholders $ 768,719 $ 281,974

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill	The following table shows an analysis of goodwill and other intangible assets included in goodwill and other intangible assets on the Company’s consolidated balance sheets: Goodwill and other intangible assets Goodwill Other intangible assets Total Balance as of December 31, 2017 Gross amount $ 199,889 $ 96,599 $ 296,488 Accumulated impairment losses and amortization (2,299 ) (51,044 ) (53,343 ) 197,590 45,555 243,145 Amortization — (5,727 ) (5,727 ) Balance as of December 31, 2018 Gross amount 199,889 96,599 296,488 Accumulated impairment losses and amortization (2,299 ) (56,771 ) (59,070 ) 197,590 39,828 237,418 Acquired during the year 13,094 18,000 31,094 Amortization — (6,286 ) (6,286 ) Balance as of December 31, 2019 Gross amount 212,983 114,599 327,582 Accumulated impairment losses and amortization (2,299 ) (63,057 ) (65,356 ) $ 210,684 $ 51,542 $ 262,226
Schedule of Goodwill and Other Intangible Assets Included In Equity Method Investments	The following table shows an analysis of goodwill and other intangible assets included in investments in other ventures, under equity method on the Company’s consolidated balance sheets: Goodwill and other intangible assets included in investments in other ventures, under equity method Goodwill Other intangible assets Total Balance as of December 31, 2017 Gross amount $ 12,318 $ 51,796 $ 64,114 Accumulated impairment losses and amortization (4,500 ) (42,880 ) (47,380 ) 7,818 8,916 16,734 Acquired during the year 2,780 11,108 13,888 Amortization — (2,886 ) (2,886 ) Balance as of December 31, 2018 Gross amount 15,098 62,904 78,002 Accumulated impairment losses and amortization (4,500 ) (45,766 ) (50,266 ) 10,598 17,138 27,736 Acquired during the year — 4 4 Amortization — (2,816 ) (2,816 ) Balance as of December 31, 2019 Gross amount 15,098 62,908 78,006 Accumulated impairment losses and amortization (4,500 ) (48,582 ) (53,082 ) $ 10,598 $ 14,326 $ 24,924
Schedule of Other Intangible Assets By Major Class	The gross carrying value and accumulated amortization by major category of other intangible assets included in goodwill and other intangible assets and investments in other ventures, under equity method on the Company’s consolidated balance sheets is shown below: Other intangible assets At December 31, 2019 Gross carrying value Accumulated amortization and impairment losses Total Customer relationships and customer lists $ 108,651 $ (69,298 ) $ 39,353 Value of business acquired 20,200 (20,200 ) — Software 12,230 (12,230 ) — Licenses 26,186 — 26,186 Patents and intellectual property 4,500 (4,500 ) — Covenants not-to-compete 4,030 (4,030 ) — Trademarks and trade names 1,710 (1,381 ) 329 $ 177,507 $ (111,639 ) $ 65,868 Other intangible assets At December 31, 2018 Gross carrying value Accumulated amortization and impairment losses Total Customer relationships and customer lists $ 97,419 $ (60,221 ) $ 37,198 Value of business acquired 20,200 (20,200 ) — Software 12,230 (12,230 ) — Licenses 19,414 — 19,414 Patents and intellectual property 4,500 (4,500 ) — Covenants not-to-compete 4,030 (4,030 ) — Trademarks and trade names 1,710 (1,356 ) 354 $ 159,503 $ (102,537 ) $ 56,966
Schedule of Expected Amortization Expense	Expected amortization of the other intangible assets, including other intangible assets recorded in investments in other ventures, under equity method, is shown below: Other intangibles Other intangible assets included in investments in other ventures, under equity method Total 2020 $ 6,317 $ 1,955 $ 8,272 2021 5,990 1,095 7,085 2022 5,602 1,095 6,697 2023 5,173 631 5,804 2024 4,716 194 4,910 2024 and thereafter 6,705 209 6,914 Total remaining amortization expense 34,503 5,179 39,682 Indefinite lived 17,039 9,147 26,186 Total $ 51,542 $ 14,326 $ 65,868

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2019
Investments [Abstract]
Schedule of Fair Value of Fixed Maturity Investments Trading	The following table summarizes the fair value of fixed maturity investments trading: December 31, December 31, U.S. treasuries $ 4,467,345 $ 3,331,411 Agencies 343,031 174,883 Municipal — 6,854 Non-U.S. government 497,392 279,818 Non-U.S. government-backed corporate 321,356 160,063 Corporate 3,075,660 2,450,244 Agency mortgage-backed 1,148,499 817,880 Non-agency mortgage-backed 294,604 278,680 Commercial mortgage-backed 468,698 282,294 Asset-backed 555,070 306,743 Total fixed maturity investments trading $ 11,171,655 $ 8,088,870 The following table summarizes the fair value of equity investments trading: December 31, December 31, Financials $ 248,189 $ 200,357 Communications and technology 79,206 42,333 Industrial, utilities and energy 38,583 24,520 Consumer 35,987 20,639 Healthcare 29,510 18,925 Basic materials 5,456 3,478 Total $ 436,931 $ 310,252
Schedule of Contractual Maturities of Fixed Maturity Investments	Contractual maturities of fixed maturity investments trading are described in the following table. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. At December 31, 2019 Amortized Cost Fair Value Due in less than one year $ 543,687 $ 544,636 Due after one through five years 5,467,501 5,522,769 Due after five through ten years 2,386,467 2,420,602 Due after ten years 211,424 216,777 Mortgage-backed 1,902,365 1,911,801 Asset-backed 555,970 555,070 Total $ 11,067,414 $ 11,171,655
Schedule of Net Investment Income	The components of net investment income are as follows: Year ended December 31, 2019 2018 2017 Fixed maturity investments $ 318,503 $ 211,973 $ 179,624 Short term investments 56,264 33,571 11,082 Equity investments 4,808 4,474 3,628 Other investments Private equity investments 14,981 477 33,999 Other 39,246 22,475 8,067 Cash and cash equivalents 7,676 3,810 1,196 441,478 276,780 237,596 Investment expenses (17,645 ) (14,914 ) (15,387 ) Net investment income $ 423,833 $ 261,866 $ 222,209
Schedule of Net Realized and Unrealized Gains (Losses) On Investments and Net Other-Than-Temporary Impairments	Net realized and unrealized gains (losses) on investments are as follows: Year ended December 31, 2019 2018 2017 Gross realized gains $ 133,409 $ 21,284 $ 49,121 Gross realized losses (43,149 ) (91,098 ) (38,832 ) Net realized gains (losses) on fixed maturity investments 90,260 (69,814 ) 10,289 Net unrealized gains (losses) on fixed maturity investments trading 170,183 (57,310 ) 8,479 Net realized and unrealized gains (losses) on investments-related derivatives 58,891 (8,784 ) (2,490 ) Net realized gains on equity investments trading sold during the period 31,062 27,739 80,027 Net unrealized gains (losses) on equity investments trading still held at reporting date 64,087 (66,900 ) 39,517 Net realized and unrealized gains (losses) on equity investments trading 95,149 (39,161 ) 119,544 Net realized and unrealized gains (losses) on investments $ 414,483 $ (175,069 ) $ 135,822
Schedule of Other Investments	The table below shows the fair value of the Company’s portfolio of other investments: At December 31, 2019 2018 Catastrophe bonds $ 781,641 $ 516,571 Private equity investments 271,047 242,647 Senior secured bank loan funds 22,598 14,482 Hedge funds 12,091 11,233 Total other investments $ 1,087,377 $ 784,933
Schedule of Equity Method Investments	The table below shows the Company’s portfolio of investments in other ventures, under equity method: 2019 2018 At December 31, Ownership % Carrying Value Ownership % Carrying Value Tower Hill Companies 24.9 % 36,779 24.9 % 38,241 Top Layer Re 50.0 % 35,363 50.0 % 46,562 Other 26.6 % 34,407 30.6 % 30,369 Total investments in other ventures, under equity method $ 106,549 $ 115,172
Schedule of Equity In Earnings of Equity Method Investments	The table below shows the Company’s equity in earnings of other ventures, under equity method: Year ended December 31, 2019 2018 2017 Tower Hill Companies $ 10,337 $ 9,605 $ (1,647 ) Top Layer Re 8,801 8,852 9,851 Other 4,086 17 (174 ) Total equity in earnings of other ventures $ 23,224 $ 18,474 $ 8,030

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis	Below is a summary of the assets and liabilities that are measured at fair value on a recurring basis and also represents the carrying amount on the Company’s consolidated balance sheets: At December 31, 2019 Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fixed maturity investments U.S. treasuries $ 4,467,345 $ 4,467,345 $ — $ — Agencies 343,031 — 343,031 — Non-U.S. government 497,392 — 497,392 — Non-U.S. government-backed corporate 321,356 — 321,356 — Corporate 3,075,660 — 3,075,660 — Agency mortgage-backed 1,148,499 — 1,148,499 — Non-agency mortgage-backed 294,604 — 294,604 — Commercial mortgage-backed 468,698 — 468,698 — Asset-backed 555,070 — 555,070 — Total fixed maturity investments 11,171,655 4,467,345 6,704,310 — Short term investments 4,566,277 — 4,566,277 — Equity investments trading 436,931 436,931 — — Other investments Catastrophe bonds 781,641 — 781,641 — Private equity investments (1) 271,047 — — 74,634 Senior secured bank loan funds (1) 22,598 — — — Hedge funds (1) 12,091 — — — Total other investments 1,087,377 — 781,641 74,634 Other assets and (liabilities) Assumed and ceded (re)insurance contracts (2) 4,731 — — 4,731 Derivatives (3) 16,937 (1,020 ) 17,957 — Total other assets and (liabilities) 21,668 (1,020 ) 17,957 4,731 $ 17,283,908 $ 4,903,256 $ 12,070,185 $ 79,365 (1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated balance sheet. (2) Included in assumed and ceded (re)insurance contracts at December 31, 2019 was $32.9 million of other assets and $28.2 million of other liabilities. (3) Refer to “Note 19 . Derivative Instruments” for additional information related to the fair value, by type of contract, of derivatives entered into by the Company. At December 31, 2018 Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fixed maturity investments U.S. treasuries $ 3,331,411 $ 3,331,411 $ — $ — Agencies 174,883 — 174,883 — Municipal 6,854 — 6,854 — Non-U.S. government 279,818 — 279,818 — Non-U.S. government-backed corporate 160,063 — 160,063 — Corporate 2,450,244 — 2,450,244 — Agency mortgage-backed 817,880 — 817,880 — Non-agency mortgage-backed 278,680 — 278,680 — Commercial mortgage-backed 282,294 — 282,294 — Asset-backed 306,743 — 306,743 — Total fixed maturity investments 8,088,870 3,331,411 4,757,459 — Short term investments 2,586,520 — 2,586,520 — Equity investments trading 310,252 310,252 — — Other investments Catastrophe bonds 516,571 — 516,571 — Private equity investments (1) 242,647 — — 54,545 Senior secured bank loan funds (1) 14,482 — — — Hedge funds (1) 11,233 — — — Total other investments 784,933 — 516,571 54,545 Other assets and (liabilities) Assumed and ceded (re)insurance contracts (2) (8,359 ) — — (8,359 ) Derivatives (3) 12,399 484 11,915 — Total other assets and (liabilities) 4,040 484 11,915 (8,359 ) $ 11,774,615 $ 3,642,147 $ 7,872,465 $ 46,186 (1) Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated balance sheet. (2) Included in assumed and ceded (re)insurance contracts at December 31, 2018 was $5.0 million of other assets and $13.3 million of other liabilities. (3) Refer to “Note 19 . Derivative Instruments” for additional information related to the fair value, by type of contract, of derivatives entered into by the Company.
Schedule of Quantitative Information Used as Level 3 Inputs	Below is a summary of quantitative information regarding the significant unobservable inputs (Level 3) used in determining the fair value of assets and liabilities measured at fair value on a recurring basis: At December 31, 2019 Fair Value Valuation Technique Unobservable Inputs Low High Weighted Average or Actual Other investments Private equity investment $ 10,327 External valuation model Manager pricing $ 103.20 $ 103.77 $ 103.20 Private equity investments 64,307 Internal valuation model Discount rate 8.0 % 10.0 % 9.0 % Liquidity discount n/a n/a 15.0 % Total other investments 74,634 Other assets and (liabilities) Assumed and ceded (re)insurance contracts 501 Internal valuation model Bond price $ 100.29 $ 106.26 $ 103.58 Liquidity discount n/a n/a 1.3 % Assumed and ceded (re)insurance contracts (8,767 ) Internal valuation model Net undiscounted cash flows n/a n/a $ (11,179 ) Expected loss ratio n/a n/a 33.1 % Discount rate n/a n/a 1.7 % Assumed and ceded (re)insurance contracts 12,997 Internal valuation model Expected loss ratio n/a n/a 0.0 % Total other assets and (liabilities) 4,731 Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs $ 79,365
Schedule of Assets and Liabilities Measured at Fair Value an a Recurring Basis Using Level 3 Inputs	Below is a reconciliation of the beginning and ending balances, for the periods shown, of assets and liabilities measured at fair value on a recurring basis using Level 3 inputs. Interest and dividend income are included in net investment income and are excluded from the reconciliation. Other investments Other assets and (liabilities) Total Balance - January 1, 2019 $ 54,545 $ (8,359 ) $ 46,186 Total realized and unrealized gains (losses) Included in other income 2,126 (2,347 ) (221 ) Total foreign exchange gains 5 — 5 Purchases 17,958 (4,553 ) 13,405 Settlements — 20 20 Amounts acquired (1) — 19,970 19,970 Balance - December 31, 2019 $ 74,634 $ 4,731 $ 79,365 (1) Represents the fair value of the other assets acquired from TMR, measured at fair value on a recurring basis using Level 3 inputs at March 22, 2019. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. Other Other assets and (liabilities) Total Balance - January 1, 2018 $ — $ (2,952 ) $ (2,952 ) Total realized and unrealized gains Included in other income — 2,901 2,901 Purchases 54,545 (9,291 ) 45,254 Settlements — 983 983 Balance - December 31, 2018 $ 54,545 $ (8,359 ) $ 46,186
Schedule of Assets and Liabilities Measured at Fair Value an a Recurring Basis Using Level 3 Inputs	Below is a reconciliation of the beginning and ending balances, for the periods shown, of assets and liabilities measured at fair value on a recurring basis using Level 3 inputs. Interest and dividend income are included in net investment income and are excluded from the reconciliation. Other investments Other assets and (liabilities) Total Balance - January 1, 2019 $ 54,545 $ (8,359 ) $ 46,186 Total realized and unrealized gains (losses) Included in other income 2,126 (2,347 ) (221 ) Total foreign exchange gains 5 — 5 Purchases 17,958 (4,553 ) 13,405 Settlements — 20 20 Amounts acquired (1) — 19,970 19,970 Balance - December 31, 2019 $ 74,634 $ 4,731 $ 79,365 (1) Represents the fair value of the other assets acquired from TMR, measured at fair value on a recurring basis using Level 3 inputs at March 22, 2019. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. Other Other assets and (liabilities) Total Balance - January 1, 2018 $ — $ (2,952 ) $ (2,952 ) Total realized and unrealized gains Included in other income — 2,901 2,901 Purchases 54,545 (9,291 ) 45,254 Settlements — 983 983 Balance - December 31, 2018 $ 54,545 $ (8,359 ) $ 46,186
Schedule of the Balances the Company has Elected to Account for at Fair Value	Below is a summary of the balances the Company has elected to account for at fair value: 2019 2018 Other investments $ 1,087,377 $ 784,933 Other assets $ 32,944 $ 4,968 Other liabilities $ 28,213 $ 13,327
Schedule of Other Investments Measured Using Net Asset Valuations	The table below shows the Company’s portfolio of other investments measured using net asset valuations as a practical expedient: At December 31, 2019 Fair Value Unfunded Redemption Frequency Redemption Redemption Private equity investments $ 196,413 $ 351,028 See below See below See below Senior secured bank loan funds 22,598 8,702 See below See below See below Hedge funds 12,091 — See below See below See below Total other investments measured using net asset valuations $ 231,102 $ 359,730

Reinsurance (Tables)

Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2019
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]
Schedule of Effect of Reinsurance and Retrocessional Activity on Premiums Written and Earned and on Net Claims and Claim Expenses Incurred	The following table sets forth the effect of reinsurance and retrocessional activity on premiums written and earned and on net claims and claim expenses incurred: Year ended December 31, 2019 2018 2017 Premiums written Direct $ 461,409 $ 337,587 $ 290,730 Assumed 4,346,341 2,972,840 2,506,810 Ceded (1,426,257 ) (1,178,525 ) (926,215 ) Net premiums written $ 3,381,493 $ 2,131,902 $ 1,871,325 Premiums earned Direct $ 404,525 $ 292,219 $ 244,285 Assumed 4,348,261 2,779,796 2,307,219 Ceded (1,414,383 ) (1,095,886 ) (833,929 ) Net premiums earned $ 3,338,403 $ 1,976,129 $ 1,717,575 Claims and claim expenses Gross claims and claim expenses incurred $ 3,221,778 $ 2,578,536 $ 3,420,388 Claims and claim expenses recovered (1,124,757 ) (1,458,518 ) (1,558,960 ) Net claims and claim expenses incurred $ 2,097,021 $ 1,120,018 $ 1,861,428

Reserve for Claims and Claim _2

Reserve for Claims and Claim Expenses (Tables)	12 Months Ended
	Dec. 31, 2019
Insurance [Abstract]
Schedule of Liability for Unpaid Claims and Claim Expenses	Year ended December 31, 2018 (Favorable) adverse development Catastrophe net claims and claim expenses Large catastrophe events 2017 Large Loss Events $ (172,512 ) Other (9,517 ) Total large catastrophe events (182,029 ) Small catastrophe events and attritional loss movements Other small catastrophe events and attritional loss movements (33,579 ) Total small catastrophe events and attritional loss movements (33,579 ) Total catastrophe and attritional net claims and claim expenses (215,608 ) Actuarial assumption changes (5,682 ) Total net favorable development of prior accident years net claims and claim expenses $ (221,290 ) The following tables detail the development of the Company’s liability for unpaid claims and claim expenses for its Property segment, allocated between large and small catastrophe net claims and claim expenses and attritional net claims and claim expenses, included in the other line item: Year ended December 31, 2019 (Favorable) adverse development Catastrophe net claims and claim expenses Large catastrophe events 2017 Large Loss Events $ (101,572 ) New Zealand Earthquake (2011) (7,497 ) Tohoku Earthquake and Tsunami (2011) (5,198 ) New Zealand Earthquake (2010) 47,071 2018 Large Loss Events 81,555 Other (31,916 ) Total large catastrophe events (17,557 ) Small catastrophe events and attritional loss movements Other small catastrophe events and attritional loss movements 5,379 Total small catastrophe events and attritional loss movements 5,379 Total catastrophe and attritional net claims and claim expenses (12,178 ) Actuarial assumption changes 9,245 Total net favorable development of prior accident years net claims and claim expenses $ (2,933 ) Year ended December 31, 2017 (Favorable) adverse development Catastrophe net claims and claim expenses Large catastrophe events Storm Sandy (2012) $ (4,395 ) April and May U.S. Tornadoes (2011) (4,177 ) New Zealand Earthquake (2010) 4,061 New Zealand Earthquake (2011) 5,807 Other (8,936 ) Total large catastrophe events (7,640 ) Small catastrophe events and attritional loss movements Tianjin Explosion (2015) (8,002 ) Fort McMurray Wildfire (2016) (6,364 ) Other small catastrophe events and attritional loss movements (24,432 ) Total small catastrophe events and attritional loss movements (38,798 ) Total catastrophe and attritional net claims and claim expenses (46,438 ) Actuarial assumption changes 842 Total net favorable development of prior accident years net claims and claim expenses $ (45,596 ) The following table details the Company’s prior year development by segment of its liability for unpaid claims and claim expenses: Year ended December 31, 2019 2018 2017 (Favorable) adverse development (Favorable) adverse development (Favorable) adverse development Property $ (2,933 ) $ (221,290 ) $ (45,596 ) Casualty and Specialty (23,882 ) (49,262 ) 6,183 Other (40 ) (197 ) (1,583 ) Total net favorable development of prior accident years net claims and claim expenses $ (26,855 ) $ (270,749 ) $ (40,996 ) The following table details the development of the Company’s liability for unpaid claims and claim expenses for its Casualty and Specialty segment: Year ended December 31, 2019 2018 2017 (Favorable) adverse development (Favorable) adverse development (Favorable) adverse development Actuarial methods - actual reported claims less than expected claims $ (52,796 ) $ (41,476 ) $ (24,836 ) Ogden Rate change — — 33,481 Actuarial assumption changes 28,914 (7,786 ) (2,462 ) Total net (favorable) adverse development of prior accident years net claims and claim expenses $ (23,882 ) $ (49,262 ) $ 6,183 The reconciliation of the net incurred and paid claims development tables to the reserve for claims and claim expenses in the consolidated balance sheet is as follows: At December 31, 2019 Net reserve for claims and claim expenses Property $ 2,288,762 Casualty and Specialty 4,304,061 Other 229 Total net reserve for claims and claim expenses 6,593,052 Reinsurance recoverable Property $ 1,785,088 Casualty and Specialty 1,005,998 Other 211 Total reinsurance recoverable 2,791,297 Total gross reserve for claims and claim expenses $ 9,384,349 The following table summarizes the Company’s claims and claim expense reserves by segment, allocated between case reserves, additional case reserves and IBNR: At December 31, 2019 Case Reserves Additional Case Reserves IBNR Total Property $ 1,253,406 $ 1,631,223 $ 1,189,221 $ 4,073,850 Casualty and Specialty 1,596,426 129,720 3,583,913 5,310,059 Other 440 — — 440 Total $ 2,850,272 $ 1,760,943 $ 4,773,134 $ 9,384,349 At December 31, 2018 Property $ 690,718 $ 1,308,307 $ 1,087,229 $ 3,086,254 Casualty and Specialty 771,537 116,877 2,096,979 2,985,393 Other 1,458 — 3,166 4,624 Total $ 1,463,713 $ 1,425,184 $ 3,187,374 $ 6,076,271 Activity in the liability for unpaid claims and claim expenses is summarized as follows: Year ended December 31, 2019 2018 2017 Net reserves as of beginning of period $ 3,704,050 $ 3,493,778 $ 2,568,730 Net incurred related to: Current year 2,123,876 1,390,767 1,902,424 Prior years (26,855 ) (270,749 ) (40,996 ) Total net incurred 2,097,021 1,120,018 1,861,428 Net paid related to: Current year 265,649 391,061 450,527 Prior years 832,405 503,708 524,298 Total net paid 1,098,054 894,769 974,825 Amounts acquired (1) 1,858,775 — — Foreign exchange (2) 31,260 (14,977 ) 38,445 Net reserves as of end of period 6,593,052 3,704,050 3,493,778 Reinsurance recoverable as of end of period 2,791,297 2,372,221 1,586,630 Gross reserves as of end of period $ 9,384,349 $ 6,076,271 $ 5,080,408 (1) Represents the fair value of TMR's reserves for claims and claim expenses, net of reinsurance recoverables, acquired at March 22, 2019. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR. (2) Reflects the impact of the foreign exchange revaluation of net reserves denominated in non-U.S. dollars as at the balance sheet date.
Schedule of Short-duration Insurance Contracts, Claims Development	The following table details the Company’s consolidated incurred claims and claim expenses and cumulative paid claims and claim expenses as of December 31, 2019 , net of reinsurance, as well as IBNR plus ACR included within the net incurred claims amounts. Incurred claims and claim expenses, net of reinsurance For the year ended December 31, At December 31, 2019 Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 IBNR and ACR (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 1,131,892 $ 1,105,041 $ 1,048,747 $ 1,033,341 $ 1,045,727 $ 1,037,725 $ 1,045,490 $ 1,043,565 $ 1,015,540 $ 1,052,931 $ 60,342 2011 — 1,989,024 1,926,506 1,827,258 1,768,793 1,738,452 1,698,378 1,683,614 1,678,015 1,664,869 55,191 2012 — — 1,138,018 1,021,668 958,139 927,438 891,981 894,168 901,049 907,212 48,297 2013 — — — 912,545 861,093 810,934 761,033 737,158 718,563 699,767 43,792 2014 — — — — 1,024,813 997,906 990,050 966,802 948,264 953,904 114,985 2015 — — — — — 1,171,023 1,156,856 1,175,927 1,145,983 1,133,632 131,005 2016 — — — — — — 1,401,451 1,458,767 1,432,001 1,426,575 251,952 2017 — — — — — — — 2,940,713 2,724,795 2,632,396 731,975 2018 — — — — — — — — 2,198,980 2,338,291 940,346 2019 — — — — — — — — — 2,280,044 1,764,899 Total $ 15,089,621 $ 4,142,784 Cumulative paid claims and claim expenses, net of reinsurance For the year ended December 31, Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 146,890 $ 334,347 $ 518,162 $ 603,060 $ 670,935 $ 746,454 $ 859,745 $ 892,480 $ 912,776 $ 928,552 2011 — 311,906 728,464 1,143,829 1,330,492 1,449,060 1,493,174 1,530,030 1,550,195 1,565,359 2012 — — 267,764 416,808 522,264 596,634 647,618 721,942 752,614 783,106 2013 — — — 131,829 340,652 434,508 496,380 554,686 587,978 615,463 2014 — — — — 230,826 432,761 554,398 630,417 691,774 741,844 2015 — — — — — 262,085 495,119 662,001 781,622 879,950 2016 — — — — — — 286,317 623,440 826,502 971,424 2017 — — — — — — — 745,098 1,067,481 1,371,477 2018 — — — — — — — — 587,619 804,566 2019 — — — — — — — — — 284,842 Total $ 8,946,583 Outstanding liabilities from accident year 2009 and prior, net of reinsurance 270,317 Claims and claim expenses, net of reinsurance, from the Company's former Bermuda-based insurance operations 229 Adjustment for unallocated claim expenses 51,876 Unamortized fair value adjustments recorded in connection with acquisitions (69,219 ) Liability for claims and claim expense, net of reinsurance, associated with RenaissanceRe UK 196,811 Liability for claims and claim expenses, net of reinsurance $ 6,593,052 The following table details the Company’s Casualty and Specialty segment incurred claims and claim expenses and cumulative paid claims and claim expenses as of December 31, 2019 , net of reinsurance, as well as IBNR plus ACR included within the net incurred claims amounts. Incurred claims and claim expenses, net of reinsurance For the year ended December 31, At December 31, 2019 Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 IBNR and ACR (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 411,733 $ 423,754 $ 411,785 $ 375,622 $ 354,254 $ 340,881 $ 339,232 $ 335,222 $ 334,105 $ 321,752 $ 9,920 2011 — 429,955 434,736 404,599 375,683 368,885 360,191 349,632 356,878 362,728 30,856 2012 — — 578,072 592,243 562,936 552,340 535,671 549,633 564,330 575,347 35,946 2013 — — — 595,287 573,399 545,364 520,088 508,536 493,815 476,828 42,700 2014 — — — — 718,082 714,298 719,432 700,982 683,510 688,675 110,431 2015 — — — — — 802,257 822,284 858,062 838,895 831,899 119,333 2016 — — — — — — 955,919 1,000,242 988,866 994,306 197,962 2017 — — — — — — — 1,300,584 1,278,229 1,284,136 436,765 2018 — — — — — — — — 1,253,151 1,283,407 666,869 2019 — — — — — — — — — 1,279,854 1,045,052 Total $ 8,098,932 $ 2,695,834 Cumulative paid claims and claim expenses, net of reinsurance For the year ended December 31, Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 42,031 $ 103,795 $ 172,588 $ 201,083 $ 220,311 $ 264,965 $ 278,585 $ 297,349 $ 300,763 $ 305,321 2011 — 48,919 138,118 178,161 209,118 241,924 262,671 277,826 292,679 300,945 2012 — — 101,914 211,241 268,565 316,439 356,591 416,315 443,792 469,130 2013 — — — 51,746 185,193 243,327 290,004 341,335 371,802 396,232 2014 — — — — 124,208 248,621 331,889 396,273 450,635 494,181 2015 — — — — — 135,254 279,985 412,819 513,077 600,785 2016 — — — — — — 166,409 365,085 502,206 620,778 2017 — — — — — — — 211,001 406,990 547,034 2018 — — — — — — — — 155,418 354,441 2019 — — — — — — — — — 125,257 Total $ 4,214,104 Outstanding liabilities from accident year 2009 and prior, net of reinsurance 266,034 Adjustment for unallocated claim expenses 32,537 Unamortized fair value adjustments recorded in connection with acquisitions (58,613 ) Liability for claims and claim expense, net of reinsurance, associated with RenaissanceRe UK 179,275 Liability for claims and claim expenses, net of reinsurance $ 4,304,061 The following table details the Company’s Property segment incurred claims and claim expenses and cumulative paid claims and claim expenses as of December 31, 2019 , net of reinsurance, as well as IBNR plus ACR included within the net incurred claims amounts. Incurred claims and claim expenses, net of reinsurance For the year ended December 31, At December 31, 2019 Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 IBNR and ACR (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 720,159 $ 681,287 $ 636,962 $ 657,719 $ 691,473 $ 696,844 $ 706,258 $ 708,343 $ 681,435 $ 731,179 $ 50,422 2011 — 1,559,069 1,491,770 1,422,659 1,393,110 1,369,567 1,338,187 1,333,982 1,321,137 1,302,141 24,335 2012 — — 559,946 429,425 395,203 375,098 356,310 344,535 336,719 331,865 12,351 2013 — — — 317,258 287,694 265,570 240,945 228,622 224,748 222,939 1,092 2014 — — — — 306,731 283,608 270,618 265,820 264,754 265,229 4,554 2015 — — — — — 368,766 334,572 317,865 307,088 301,733 11,672 2016 — — — — — — 445,532 458,525 443,135 432,269 53,990 2017 — — — — — — — 1,640,129 1,446,566 1,348,260 295,210 2018 — — — — — — — — 945,829 1,054,884 273,477 2019 — — — — — — — — — 1,000,190 719,847 Total $ 6,990,689 $ 1,446,950 Cumulative paid claims and claim expenses, net of reinsurance For the year ended December 31, Accident Year 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) (unaudited) 2010 $ 104,859 $ 230,552 $ 345,574 $ 401,977 $ 450,624 $ 481,489 $ 581,160 $ 595,131 $ 612,013 $ 623,231 2011 — 262,987 590,346 965,668 1,121,374 1,207,136 1,230,503 1,252,204 1,257,516 1,264,414 2012 — — 165,850 205,567 253,699 280,195 291,027 305,627 308,822 313,976 2013 — — — 80,083 155,459 191,181 206,376 213,351 216,176 219,231 2014 — — — — 106,618 184,140 222,509 234,144 241,139 247,663 2015 — — — — — 126,831 215,134 249,182 268,545 279,165 2016 — — — — — — 119,908 258,355 324,296 350,646 2017 — — — — — — — 534,097 660,491 824,443 2018 — — — — — — — — 432,201 450,125 2019 — — — — — — — — — 159,585 Total $ 4,732,479 Outstanding liabilities from accident year 2009 and prior, net of reinsurance 4,283 Adjustment for unallocated claim expenses 19,339 Unamortized fair value adjustments recorded in connection with acquisitions (10,606 ) Liability for claims and claim expense, net of reinsurance, associated with RenaissanceRe UK 17,536 Liability for claims and claim expenses, net of reinsurance $ 2,288,762 The following table details the Company's cumulative number of reported claims for its excess of loss reinsurance contracts allocated by segment: At December 31, 2019 Cumulative number of reported claims Accident Year Property Casualty and Specialty 2010 835 1,215 2011 1,388 1,964 2012 922 2,263 2013 799 2,712 2014 744 3,421 2015 758 3,783 2016 1,089 4,135 2017 2,215 3,294 2018 2,050 2,148 2019 861 816
Schedule of Short-duration Insurance Contracts, Schedule of Historical Claims Duration	The following is unaudited supplementary information about average historical claims duration by segment: Average annual percentage payout of incurred claims by age, net of reinsurance (number of years) At December 31, 2019 1 2 3 4 5 6 7 8 9 10 Property 29.9 % 17.0 % 17.8 % 8.7 % 5.4 % 2.7 % 4.9 % 1.0 % 1.2 % 1.5 % Casualty and Specialty 14.3 % 18.4 % 13.0 % 10.3 % 8.8 % 8.2 % 4.6 % 4.7 % 1.7 % 1.4 %

Debt and Credit Facilities (Tab

Debt and Credit Facilities (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments	A summary of the Company’s debt obligations on its consolidated balance sheets is set forth below: December 31, 2019 December 31, 2018 Fair Value Carrying Value Fair Value Carrying Value 3.600% Senior Notes due 2029 $ 424,920 $ 391,475 $ — $ — 3.450% Senior Notes due 2027 314,070 296,292 283,680 295,797 3.700% Senior Notes due 2025 318,567 298,057 292,557 297,688 5.750% Senior Notes due 2020 251,030 249,931 255,938 249,602 4.750% Senior Notes due 2025 (DaVinciRe) (1) 160,031 148,350 142,539 148,040 $ 1,468,618 $ 1,384,105 $ 974,714 $ 991,127 (1) RenaissanceRe owns a noncontrolling economic interest in its joint venture DaVinciRe. Because RenaissanceRe controls a majority of DaVinciRe’s outstanding voting rights, the consolidated financial statements of DaVinciRe are included in the consolidated financial statements of RenaissanceRe. However, RenaissanceRe does not guarantee or provide credit support for DaVinciRe and RenaissanceRe’s financial exposure to DaVinciRe is limited to its investment in DaVinciRe’s shares and counterparty credit risk arising from reinsurance transactions.
Schedule of Aggregate Amount of Maturities Related to the Company's Debt Obligations	The following table sets forth the scheduled maturity of the Company’s aggregate amount of its debt obligation reflected on its consolidated balance sheet at December 31, 2019 : 2020 $ 250,000 2021 — 2022 — 2023 — 2024 — After 2024 1,150,000 Unamortized discount and debt issuance expenses (15,895 ) $ 1,384,105
Schedule of Credit Facilities	The outstanding amounts issued or drawn under each of the Company’s significant credit facilities is set forth below: At December 31, 2019 Issued or Drawn Revolving Credit Facility (1) $ — Bilateral Letter of Credit Facilities Secured 298,063 Unsecured 381,770 Funds at Lloyd’s Letter of Credit Facility 290,000 TMR Letters of Credit (2) 140,923 $ 1,110,756 (1) At December 31, 2019 , no amounts were issued or drawn under this facility. (2) These letters of credit were transferred to us in connection with the acquisition of TMR. Refer to “Note 3 . Acquisition of Tokio Millennium Re” for additional information related to the acquisition of TMR.

Noncontrolling Interests (Table

Noncontrolling Interests (Tables)	12 Months Ended
	Dec. 31, 2019
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest [Abstract]
Schedule of Redeemable Noncontrolling Interest	The activity in redeemable noncontrolling interest – DaVinciRe is detailed in the table below: Year ended December 31, 2019 2018 Beginning balance $ 1,034,946 $ 1,011,659 Redemption of shares from redeemable noncontrolling interests, net of adjustments (1,148 ) (4,351 ) Sale of shares to redeemable noncontrolling interests 274,699 — Net income attributable to redeemable noncontrolling interests 127,084 27,638 Ending balance $ 1,435,581 $ 1,034,946 The activity in redeemable noncontrolling interest – Vermeer is detailed in the table below: Year ended December 31, 2019 2018 Beginning balance $ 599,989 $ — Sale of shares to redeemable noncontrolling interest 355,000 600,000 Net income (loss) attributable to redeemable noncontrolling interest 48,626 (11 ) Ending balance $ 1,003,615 $ 599,989 The activity in redeemable noncontrolling interest – Medici is detailed in the table below: Year ended December 31, 2019 2018 Beginning balance $ 416,765 $ 284,847 Redemption of shares from redeemable noncontrolling interests, net of adjustments (47,401 ) (90,490 ) Sale of shares to redeemable noncontrolling interests 236,989 208,482 Net income attributable to redeemable noncontrolling interests 25,759 13,926 Ending balance $ 632,112 $ 416,765 A summary of the Company’s redeemable noncontrolling interests on its consolidated balance sheets is set forth below: December 31, December 31, Redeemable noncontrolling interest - DaVinciRe $ 1,435,581 $ 1,034,946 Redeemable noncontrolling interest - Medici 632,112 416,765 Redeemable noncontrolling interest - Vermeer 1,003,615 599,989 Redeemable noncontrolling interests $ 3,071,308 $ 2,051,700 A summary of the Company’s redeemable noncontrolling interests on its consolidated statements of operations is set forth below: Year ended December 31, 2019 2018 2017 Redeemable noncontrolling interest - DaVinciRe $ 127,084 $ 27,638 $ (134,860 ) Redeemable noncontrolling interest - Medici 25,759 13,926 2,578 Redeemable noncontrolling interest - Vermeer 48,626 (11 ) — Net income (loss) attributable to redeemable noncontrolling interests $ 201,469 $ 41,553 $ (132,282 )

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Rollforward of Common Stock Issued and Outstanding	The following table is a summary of changes in common shares issued and outstanding: Year ended December 31, 2019 2018 2017 (thousands of shares) Issued and outstanding shares – January 1 42,207 40,024 41,187 Issuance of shares 1,739 1,947 — Repurchase of shares — — (1,322 ) Exercise of options and issuance of restricted stock awards 202 236 159 Issued and outstanding shares – December 31 44,148 42,207 40,024

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Earnings Per Common Share	The following table sets forth the computation of basic and diluted earnings per common share: Year ended December 31, 2019 2018 2017 (common shares in thousands) Numerator: Net income (loss) available (attributable) to RenaissanceRe common shareholders $ 712,042 $ 197,276 $ (244,770 ) Amount allocated to participating common shareholders (1) (8,545 ) (2,121 ) (457 ) Net income (loss) allocated to RenaissanceRe common shareholders $ 703,497 $ 195,155 $ (245,227 ) Denominator: Denominator for basic income (loss) per RenaissanceRe common share - weighted average common shares 43,119 39,732 39,854 Per common share equivalents of employee stock options and performance shares 56 23 — Denominator for diluted income (loss) per RenaissanceRe common share - adjusted weighted average common shares and assumed conversions 43,175 39,755 39,854 Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – basic $ 16.32 $ 4.91 $ (6.15 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – diluted $ 16.29 $ 4.91 $ (6.15 ) (1) Represents earnings attributable to holders of unvested shares issued pursuant to the Company’s stock compensation plans and to the Company’s non-employee directors.

Taxation (Tables)

Taxation (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	The following is a summary of the Company’s income (loss) before taxes allocated between domestic and foreign operations: Year ended December 31, 2019 2018 2017 Domestic Bermuda $ 861,068 $ 349,959 $ (262,827 ) Foreign U.S. 102,724 (56,261 ) (11,897 ) Australia 3,390 — — Switzerland 14,255 166 — Ireland (388 ) 551 617 Singapore (6,334 ) (3,226 ) (12,421 ) U.K. (7,233 ) (28,574 ) (41,656 ) Income (loss) before taxes $ 967,482 $ 262,615 $ (328,184 )
Schedule of Components of Income Tax (Expense) Benefit	Income tax (expense) benefit is comprised as follows: Year ended December 31, 2019 Current Deferred Total Total income tax expense $ (2,128 ) $ (15,087 ) $ (17,215 ) Year ended December 31, 2018 Total income tax (expense) benefit $ (1,668 ) $ 7,970 $ 6,302 Year ended December 31, 2017 Total income tax expense $ (844 ) $ (25,643 ) $ (26,487 )
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the difference between the provision for income taxes and the expected tax provision at the weighted average tax rate is as follows: Year ended December 31, 2019 2018 2017 Expected income tax (expense) benefit $ (22,874 ) $ 17,697 $ 14,216 Nondeductible expenses (7,059 ) (370 ) (276 ) Change in valuation allowance (5,481 ) (5,255 ) (11,718 ) Withholding tax (665 ) (1,831 ) (216 ) Effect of change in tax rate (262 ) (708 ) (38,083 ) Non-taxable foreign exchange gains (losses) (4 ) 586 2,574 Tax exempt income 400 944 3,794 Transfer pricing 2,503 (2,481 ) (11 ) GAAP to statutory accounting difference 6,553 — — Foreign branch adjustments 7,315 — — U.S. base erosion and anti-abuse tax — (1,271 ) — Other 2,359 (1,009 ) 3,233 Income tax (expense) benefit $ (17,215 ) $ 6,302 $ (26,487 )
Schedule of Deferred Tax Assets and Liabilities	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are presented below: At December 31, 2019 2018 Deferred tax assets Tax loss and credit carryforwards $ 111,835 $ 60,395 Unearned premiums 14,430 10,108 Deferred finance charges 10,160 14,646 Reserve for claims and claim expenses 8,984 17,345 Accrued expenses 7,196 4,292 Deferred underwriting results 4,033 3,514 Premiums receivable 3,412 — Investments — 4,427 160,050 114,727 Deferred tax liabilities Deferred acquisition expenses (16,296 ) (11,801 ) VOBA (12,673 ) — Investments (6,468 ) — Intangible assets (2,891 ) — Amortization and depreciation (2,133 ) (2,992 ) (40,461 ) (14,793 ) Net deferred tax asset before valuation allowance 119,589 99,934 Valuation allowance (75,685 ) (35,271 ) Net deferred tax asset $ 43,904 $ 64,663

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting, Measurement Disclosures [Abstract]
Schedule of Significant Components of the Company's Revenues and Expenses	A summary of the significant components of the Company’s revenues and expenses by segment is as follows: Year ended December 31, 2019 Property Casualty and Specialty Other Total Gross premiums written $ 2,430,985 $ 2,376,765 $ — $ 4,807,750 Net premiums written $ 1,654,259 $ 1,727,234 $ — $ 3,381,493 Net premiums earned $ 1,627,494 $ 1,710,909 $ — $ 3,338,403 Net claims and claim expenses incurred 965,424 1,131,637 (40 ) 2,097,021 Acquisition expenses 313,761 448,678 (207 ) 762,232 Operational expenses 139,015 84,546 (828 ) 222,733 Underwriting income (loss) $ 209,294 $ 46,048 $ 1,075 256,417 Net investment income 423,833 423,833 Net foreign exchange losses (2,938 ) (2,938 ) Equity in earnings of other ventures 23,224 23,224 Other income 4,949 4,949 Net realized and unrealized gains on investments 414,483 414,483 Corporate expenses (94,122 ) (94,122 ) Interest expense (58,364 ) (58,364 ) Income before taxes and redeemable noncontrolling interests 967,482 Income tax expense (17,215 ) (17,215 ) Net income attributable to redeemable noncontrolling interests (201,469 ) (201,469 ) Dividends on preference shares (36,756 ) (36,756 ) Net income available to RenaissanceRe common shareholders $ 712,042 Net claims and claim expenses incurred – current accident year $ 968,357 $ 1,155,519 $ — $ 2,123,876 Net claims and claim expenses incurred – prior accident years (2,933 ) (23,882 ) (40 ) (26,855 ) Net claims and claim expenses incurred – total $ 965,424 $ 1,131,637 $ (40 ) $ 2,097,021 Net claims and claim expense ratio – current accident year 59.5 % 67.5 % 63.6 % Net claims and claim expense ratio – prior accident years (0.2 )% (1.4 )% (0.8 )% Net claims and claim expense ratio – calendar year 59.3 % 66.1 % 62.8 % Underwriting expense ratio 27.8 % 31.2 % 29.5 % Combined ratio 87.1 % 97.3 % 92.3 % Year ended December 31, 2018 Property Casualty and Specialty Other Total Gross premiums written $ 1,760,926 $ 1,549,501 $ — $ 3,310,427 Net premiums written $ 1,055,188 $ 1,076,714 $ — $ 2,131,902 Net premiums earned $ 1,050,831 $ 925,298 $ — $ 1,976,129 Net claims and claim expenses incurred 497,895 622,320 (197 ) 1,120,018 Acquisition expenses 177,912 255,079 (2 ) 432,989 Operational expenses 112,954 64,883 430 178,267 Underwriting income (loss) $ 262,070 $ (16,984 ) $ (231 ) 244,855 Net investment income 261,866 261,866 Net foreign exchange losses (12,428 ) (12,428 ) Equity in earnings of other ventures 18,474 18,474 Other income 5,969 5,969 Net realized and unrealized losses on investments (175,069 ) (175,069 ) Corporate expenses (33,983 ) (33,983 ) Interest expense (47,069 ) (47,069 ) Income before taxes and redeemable noncontrolling interests 262,615 Income tax benefit 6,302 6,302 Net income attributable to redeemable noncontrolling interests (41,553 ) (41,553 ) Dividends on preference shares (30,088 ) (30,088 ) Net income available to RenaissanceRe common shareholders $ 197,276 Net claims and claim expenses incurred – current accident year $ 719,185 $ 671,582 $ — $ 1,390,767 Net claims and claim expenses incurred – prior accident years (221,290 ) (49,262 ) (197 ) (270,749 ) Net claims and claim expenses incurred – total $ 497,895 $ 622,320 $ (197 ) $ 1,120,018 Net claims and claim expense ratio – current accident year 68.4 % 72.6 % 70.4 % Net claims and claim expense ratio – prior accident years (21.0 )% (5.3 )% (13.7 )% Net claims and claim expense ratio – calendar year 47.4 % 67.3 % 56.7 % Underwriting expense ratio 27.7 % 34.5 % 30.9 % Combined ratio 75.1 % 101.8 % 87.6 % Year ended December 31, 2017 Property Casualty and Specialty Other Total Gross premiums written $ 1,440,437 $ 1,357,110 $ (7 ) $ 2,797,540 Net premiums written $ 978,014 $ 893,307 $ 4 $ 1,871,325 Net premiums earned $ 931,070 $ 786,501 $ 4 $ 1,717,575 Net claims and claim expenses incurred 1,297,985 565,026 (1,583 ) 1,861,428 Acquisition expenses 113,816 233,077 (1 ) 346,892 Operational expenses 94,194 66,548 36 160,778 Underwriting (loss) income $ (574,925 ) $ (78,150 ) $ 1,552 (651,523 ) Net investment income 222,209 222,209 Net foreign exchange gains 10,628 10,628 Equity in earnings of other ventures 8,030 8,030 Other income 9,415 9,415 Net realized and unrealized gains on investments 135,822 135,822 Corporate expenses (18,572 ) (18,572 ) Interest expense (44,193 ) (44,193 ) Loss before taxes and redeemable noncontrolling interests (328,184 ) Income tax expense (26,487 ) (26,487 ) Net loss attributable to redeemable noncontrolling interests 132,282 132,282 Dividends on preference shares (22,381 ) (22,381 ) Net loss attributable to RenaissanceRe common shareholders $ (244,770 ) Net claims and claim expenses incurred – current accident year $ 1,343,581 $ 558,843 $ — $ 1,902,424 Net claims and claim expenses incurred – prior accident years (45,596 ) 6,183 (1,583 ) (40,996 ) Net claims and claim expenses incurred – total $ 1,297,985 $ 565,026 $ (1,583 ) $ 1,861,428 Net claims and claim expense ratio – current accident year 144.3 % 71.1 % 110.8 % Net claims and claim expense ratio – prior accident years (4.9 )% 0.7 % (2.4 )% Net claims and claim expense ratio – calendar year 139.4 % 71.8 % 108.4 % Underwriting expense ratio 22.3 % 38.1 % 29.5 % Combined ratio 161.7 % 109.9 % 137.9 %
Schedule of Gross Premiums Written Allocated to the Territory of Coverage Exposure	The following is a summary of the Company’s gross premiums written allocated to the territory of coverage exposure: Year ended December 31, 2019 2018 2017 Property U.S. and Caribbean $ 1,368,205 $ 978,063 $ 954,269 Worldwide 643,744 464,311 305,915 Europe 182,544 144,857 49,486 Japan 90,328 71,601 49,821 Worldwide (excluding U.S.) (1) 79,393 66,872 48,182 Australia and New Zealand 32,203 19,273 14,151 Other 34,568 15,949 18,613 Total Property 2,430,985 1,760,926 1,440,437 Casualty and Specialty Worldwide 935,626 776,976 686,253 U.S. and Caribbean 1,071,170 667,125 622,757 Worldwide (excluding U.S.) (1) 25,291 31,734 10,104 Europe 227,178 15,296 9,752 Australia and New Zealand 34,053 3,667 4,141 Other 83,447 54,703 24,103 Total Casualty and Specialty 2,376,765 1,549,501 1,357,110 Other category — — (7 ) Total gross premiums written $ 4,807,750 $ 3,310,427 $ 2,797,540 (1) The category “Worldwide (excluding U.S.)” consists of contracts that cover more than one geographic region (other than the U.S.).

Stock Incentive Compensation _2

Stock Incentive Compensation and Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Schedule of Share-based Payment Award, Performance Shares, Valuation Assumptions	The following are the weighted average-assumptions used to estimate the fair value for all performance share awards issued in each respective year. Performance Share Awards Year ended December 31, 2019 2018 Expected volatility (1) n/a 15.8% Expected term (in years) n/a n/a Expected dividend yield n/a n/a Risk-free interest rate (1) n/a 1.85% - 2.36% (1) The expected volatility and risk-free interest rate applied are specific to each tranche of performance share awards.
Schedule of Share-based Compensation, Options and Premium Option Plan Awards	The following is a summary of activity under the Company’s stock compensation plans. Stock Options Weighted options outstanding Weighted average exercise price Weighted average remaining contractual life Aggregate intrinsic value Range of exercise prices Balance, December 31, 2016 206,795 $ 53.17 0.9 $ 17,174 $50.71 - $59.66 Options granted — — — Options forfeited — — Options expired — — Options exercised (174,794 ) 53.04 $ 15,945 $50.71 - $59.66 Balance, December 31, 2017 32,001 $ 53.86 0.2 $ 2,295 $ 53.86 Options granted — — — Options forfeited — — Options expired — — Options exercised (32,001 ) 53.86 $ 2,320 $ 53.86 Balance, December 31, 2018 — $ — 0.0 $ — $ —
Schedule of Share-based Compensation, Cash Settled Restricted Stock Units and Performance Shares	Cash Settled Restricted Stock Units Number of shares Nonvested at December 31, 2016 308,344 Awards granted 98,067 Awards vested (122,088 ) Awards forfeited (21,993 ) Nonvested at December 31, 2017 262,330 Awards granted — Awards vested (108,344 ) Awards forfeited (7,069 ) Nonvested at December 31, 2018 146,917 Awards granted — Awards vested (80,012 ) Awards forfeited (3,161 ) Nonvested at December 31, 2019 63,744 Performance Share Awards Number of shares (1) Weighted average grant-date fair value Nonvested at December 31, 2016 211,381 $ 44.63 Awards granted 64,947 $ 65.27 Awards vested (62,499 ) $ 43.51 Awards forfeited (46,156 ) Nonvested at December 31, 2017 167,673 $ 53.11 Awards granted 83,475 $ 60.69 Awards vested (16,456 ) $ 53.79 Awards forfeited (82,241 ) Nonvested at December 31, 2018 152,451 $ 57.21 Awards granted 58,050 $ 146.10 Awards vested (21,730 ) $ 49.90 Awards forfeited (43,924 ) Nonvested at December 31, 2019 144,847 $ 94.70 (1) For performance share awards, the number of shares is stated at the maximum number that can be attained if the performance conditions are fully met. Forfeitures represent shares forfeited due to vesting below the maximum attainable as a result of the Company not fully meeting the performance conditions.
Schedule of Share-based Compensation, Restricted Stock Awards	Restricted Stock Awards Employee restricted stock awards Non-employee director restricted stock awards Total restricted stock awards Number of shares Weighted average grant date fair value Number of shares Weighted Number of shares Weighted Nonvested at December 31, 2016 402,170 $ 103.34 25,545 $ 107.95 427,715 $ 103.61 Awards granted 116,345 148.66 12,193 150.05 128,538 148.79 Awards vested (185,478 ) 100.17 (17,612 ) 110.66 (203,090 ) 101.08 Awards forfeited — — — — — — Nonvested at December 31, 2017 333,037 $ 120.93 20,126 $ 131.09 353,163 $ 121.51 Awards granted 255,799 132.70 12,169 127.29 267,968 132.79 Awards vested (139,454 ) 112.70 (9,761 ) 123.59 (149,215 ) 113.41 Awards forfeited (1,642 ) 134.38 — — (1,642 ) 134.38 Nonvested at December 31, 2018 447,740 $ 130.37 22,534 $ 132.29 470,274 $ 130.46 Awards granted 242,832 146.92 11,444 147.43 254,276 146.94 Awards vested (165,245 ) 124.71 (12,972 ) 131.88 (178,217 ) 125.23 Awards forfeited (14,467 ) 136.16 — — (14,467 ) 136.16 Nonvested at December 31, 2019 510,860 $ 139.91 21,006 $ 140.79 531,866 $ 139.94

Statutory Requirements (Tables)

Statutory Requirements (Tables)	12 Months Ended
	Dec. 31, 2019
Insurance [Abstract]
Schedule of Actual and Required Statutory Capital and Surplus	The statutory capital and surplus, required minimum statutory capital and surplus and unrestricted net assets of the Company’s regulated insurance operations in its most significant regulatory jurisdictions are detailed below: Bermuda (1) Switzerland (2) U.K. (3) (4) U.S. At December 31, 2019 2018 2019 2018 2019 2018 2019 2018 Statutory capital and surplus $ 5,325,749 $ 4,366,089 $ 580,235 $ — $ 675,864 $ 519,689 $ 677,832 $ 502,803 Required statutory capital and surplus 1,201,529 957,650 465,900 — 675,864 519,689 397,447 306,628 Unrestricted net assets 1,107,586 931,387 102,943 — — — 46,630 31,228 (1) The Company's Bermuda-domiciled insurance subsidiaries’ capital and surplus is based on the relevant insurer’s statutory financial statements and required statutory capital and surplus is based on the MSM. (2) RenaissanceRe Europe’s statutory capital and surplus and required statutory capital and surplus incorporate a full year of statutory net loss and risk capital, respectively. (3) With respect to statutory capital and surplus and required statutory capital and surplus, and as described below, underwriting capacity of a member of Lloyd’s must be supported by providing a deposit in the form of cash, securities or letters of credit, which are referred to as Funds at Lloyd’s (“FAL”). FAL is determined by Lloyd’s and is based on Syndicate 1458’s solvency and capital requirements as calculated through its internal model. (4) Syndicate 1458 is capitalized by its FAL, with the related assets not held on its balance sheet. As such, unrestricted net assets is not applicable to Syndicate 1458; however, the Company can make an application to obtain approval from Lloyd’s to have funds released to RenaissanceRe from Syndicate 1458, subject to passing a Lloyd’s release test.
Schedule of Statutory Net (Loss) Income	Statutory net income (loss) of the Company’s regulated insurance operations in its most significant regulatory jurisdictions are detailed below: Statutory Net Income (Loss) Bermuda Switzerland U.K. U.S. Year ended December 31, 2019 $ 657,182 $ (14,679 ) $ (666,595 ) $ 37,827 Year ended December 31, 2018 326,386 — (6,692 ) 25,851 Year ended December 31, 2017 (334,142 ) — (57,050 ) (3,627 )

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Summary of Derivative Instruments [Abstract]
Schedule of Location on Consolidated Balance Sheets and Fair Value of Principal Derivative Instruments	The tables below show the gross and net amounts of recognized derivative assets and liabilities at fair value, including the location on the consolidated balance sheets of the Company’s principal derivative instruments: Derivative Assets At December 31, 2019 Gross Amounts of Recognized Assets Gross Amounts Offset in the Balance Sheet Net Amounts of Assets Presented in the Balance Sheet Balance Sheet Location Collateral Net Amount Derivative instruments not designated as hedges Interest rate futures $ 234 $ 122 $ 112 Other assets $ — $ 112 Foreign currency forward contracts (1) 22,702 2,418 20,284 Other assets — 20,284 Foreign currency forward contracts (2) 1,082 622 460 Other assets — 460 Credit default swaps 37 — 37 Other assets — 37 Total return swaps 3,744 — 3,744 Other assets 3,601 143 Equity futures 291 — 291 Other assets — 291 Total derivative instruments not designated as hedges 28,090 3,162 24,928 3,601 21,327 Derivative instruments designated as hedges Foreign currency forward contracts (3) 64 667 (603 ) Other assets — (603 ) Total derivative instruments designated as hedges 64 667 (603 ) — (603 ) Total $ 28,154 $ 3,829 $ 24,325 $ 3,601 $ 20,724 Derivative Liabilities At December 31, 2019 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Balance Sheet Net Amounts of Liabilities Presented in the Balance Sheet Balance Sheet Location Collateral Pledged Net Amount Derivative instruments not designated as hedges Interest rate futures $ 1,545 $ 122 $ 1,423 Other liabilities $ 1,423 $ — Interest rate swaps 50 — 50 Other liabilities 50 — Foreign currency forward contracts (1) 3,808 28 3,780 Other liabilities — 3,780 Foreign currency forward contracts (2) 939 622 317 Other liabilities — 317 Total derivative instruments not designated as hedges 6,342 772 5,570 1,473 4,097 Derivative instruments designated as hedges Foreign currency forward contracts (3) 1,818 — 1,818 Other liabilities — 1,818 Total $ 8,160 $ 772 $ 7,388 $ 1,473 $ 5,915 (1) Contracts used to manage foreign currency risks in underwriting and non-investment operations. (2) Contracts used to manage foreign currency risks in investment operations. (3) Contracts designated as hedges of a net investment in a foreign operation. Derivative Assets At December 31, 2018 Gross Amounts of Recognized Assets Gross Amounts Offset in the Balance Sheet Net Amounts of Assets Presented in the Balance Sheet Balance Sheet Location Collateral Net Amount Derivative instruments not designated as hedges Interest rate futures $ 971 $ 636 $ 335 Other assets $ — $ 335 Interest rate swaps 860 — 860 Other assets — 860 Foreign currency forward contracts (1) 16,459 2,260 14,199 Other assets — 14,199 Foreign currency forward contracts (2) 3,194 71 3,123 Other assets — 3,123 Equity futures 1,390 977 413 Other assets — 413 Total $ 22,874 $ 3,944 $ 18,930 $ — $ 18,930 Derivative Liabilities At December 31, 2018 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Balance Sheet Net Amounts of Liabilities Presented in the Balance Sheet Balance Sheet Location Collateral Pledged Net Amount Derivative instruments not designated as hedges Interest rate futures $ 910 $ 636 $ 273 Other liabilities $ 273 $ — Interest rate swaps 506 — 506 Other liabilities 254 252 Foreign currency forward contracts (1) 4,154 — 4,154 Other liabilities — 4,154 Foreign currency forward contracts (2) 72 71 1 Other liabilities — 1 Credit default swaps 1,606 — 1,606 Other liabilities 1,605 1 Equity futures 977 977 — Other liabilities — — Total $ 8,225 $ 1,684 $ 6,540 $ 2,132 $ 4,408 (1) Contracts used to manage foreign currency risks in underwriting and non-investment operations. (2) Contracts used to manage foreign currency risks in investment operations.
Schedule of Gain (Loss) Recognized in Consolidated Statements of Operations Related to Principal Derivative Instruments	The location and amount of the gain (loss) recognized in the Company’s consolidated statements of operations related to its principal derivative instruments are shown in the following table: Location of gain (loss) recognized on derivatives Amount of gain (loss) recognized on derivatives Year ended December 31, 2019 2018 2017 Derivative instruments not designated as hedges Interest rate futures Net realized and unrealized gains (losses) on investments $ 16,848 $ 6,109 $ (3,252 ) Interest rate swaps Net realized and unrealized gains (losses) on investments 1,488 (84 ) 436 Foreign currency forward contracts (1) Net foreign exchange losses 12,617 3,840 9,628 Foreign currency forward contracts (2) Net foreign exchange losses (1,605 ) 5,736 (916 ) Credit default swaps Net realized and unrealized gains (losses) on investments 7,043 (3,106 ) 326 Total return swaps Net realized and unrealized gains (losses) on investments 12,155 — — Equity futures Net realized and unrealized gains (losses) on investments 21,357 (515 ) — Total derivative instruments not designated as hedges 69,903 11,980 6,222 Derivative instruments designated as hedges Foreign currency forward contracts (3) Accumulated other comprehensive income (loss) 959 — — Total $ 70,862 $ 11,980 $ 6,222 (1) Contracts used to manage foreign currency risks in underwriting and non-investment operations. (2) Contracts used to manage foreign currency risks in investment operations. (3) Contracts designated as hedges of a net investment in a foreign operation.
Schedule of Derivative Instruments Designated as Hedges of a Net Investment in a Foreign Operation	The table below provides a summary of derivative instruments designated as hedges of a net investment in a foreign operation, including the weighted average U.S. dollar equivalent of foreign denominated net assets that were hedged and the resulting derivative gain that was recorded in foreign currency translation adjustments, net of tax, within accumulated other comprehensive income (loss) on the Company’s consolidated statements of changes in shareholders’ equity: Year ended December 31, 2019 2018 Weighted average of U.S. dollar equivalent of foreign denominated net assets $ 81,264 $ — Derivative gains (1) $ 959 $ — (1) Derivative gains from derivative instruments designated as hedges of the net investment in a foreign operation are recorded in foreign currency translation adjustments, net of tax, within accumulated other comprehensive income (loss) on the Company’s consolidated statements of changes in shareholders’ equity.

Commitments, Contingencies an_2

Commitments, Contingencies and Other Items (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Payments, Operating Leases	Future minimum lease payments under existing operating and finance leases are detailed below, excluding the bargain renewal option on the finance lease related to office space in Bermuda: Future minimum lease payments Operating leases Finance leases 2020 $ 7,912 $ 3,336 2021 7,684 3,336 2022 6,967 3,336 2023 3,959 2,830 2024 2,850 2,661 After 2024 11,285 10,129 Future minimum lease payments under existing leases $ 40,657 $ 25,628
Schedule of Future Minimum Payments, Finance Leases	Future minimum lease payments under existing operating and finance leases are detailed below, excluding the bargain renewal option on the finance lease related to office space in Bermuda: Future minimum lease payments Operating leases Finance leases 2020 $ 7,912 $ 3,336 2021 7,684 3,336 2022 6,967 3,336 2023 3,959 2,830 2024 2,850 2,661 After 2024 11,285 10,129 Future minimum lease payments under existing leases $ 40,657 $ 25,628

Quarterly Financial Informati_2

Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Data [Abstract]
Quarterly Financial Information (Unaudited)	Quarter Ended March 31, Quarter Ended June 30, Quarter Ended September 30, Quarter Ended December 31, 2019 2018 2019 2018 2019 2018 2019 2018 Revenues Gross premiums written $ 1,564,295 $ 1,159,652 $ 1,476,908 $ 977,343 $ 861,068 $ 625,677 $ 905,479 $ 547,755 Net premiums written $ 929,031 $ 663,044 $ 1,022,965 $ 604,509 $ 704,130 $ 453,255 $ 725,367 $ 411,094 (Increase) decrease in unearned premiums (379,003 ) (222,762 ) (111,463 ) (175,124 ) 202,618 78,594 244,758 163,519 Net premiums earned 550,028 440,282 911,502 429,385 906,748 531,849 970,125 574,613 Net investment income 81,462 56,476 115,832 71,356 113,844 80,696 112,695 53,338 Net foreign exchange (losses) gains (2,846 ) 3,757 9,309 (10,687 ) (8,275 ) (4,566 ) (1,126 ) (932 ) Equity in earnings of other ventures 4,661 857 6,812 5,826 5,877 7,648 5,874 4,143 Other income (loss) 3,171 (1,242 ) 922 1,225 1,016 497 (160 ) 5,489 Net realized and unrealized gains (losses) on investments 170,645 (82,144 ) 194,003 (17,901 ) 31,938 13,630 17,897 (88,654 ) Total revenues 807,121 417,986 1,238,380 479,204 1,051,148 629,754 1,105,305 547,997 Expenses Net claims and claim expenses incurred 227,035 171,703 453,373 60,167 654,520 410,510 762,093 477,638 Acquisition costs 123,951 97,711 227,482 105,052 202,181 109,761 208,618 120,465 Operational expenses 44,933 41,272 59,814 37,543 53,415 40,593 64,571 58,859 Corporate expenses 38,789 6,733 23,847 8,301 13,844 6,841 17,642 12,108 Interest expense 11,754 11,767 15,534 11,768 15,580 11,769 15,496 11,765 Total expenses 446,462 329,186 780,050 222,831 939,540 579,474 1,068,420 680,835 Income (loss) before taxes 360,659 88,800 458,330 256,373 111,608 50,280 36,885 (132,838 ) Income tax (expense) benefit (7,531 ) 3,407 (9,475 ) (4,506 ) (3,664 ) (1,451 ) 3,455 8,852 Net income (loss) 353,128 92,207 448,855 251,867 107,944 48,829 40,340 (123,986 ) Net (income) loss attributable to redeemable noncontrolling interests (70,222 ) (29,899 ) (71,812 ) (54,483 ) (62,057 ) (6,440 ) 2,622 49,269 Net income (loss) available (attributable) to RenaissanceRe 282,906 62,308 377,043 197,384 45,887 42,389 42,962 (74,717 ) Dividends on preference shares (9,189 ) (5,595 ) (9,189 ) (5,596 ) (9,189 ) (9,708 ) (9,189 ) (9,189 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders $ 273,717 $ 56,713 $ 367,854 $ 191,788 $ 36,698 $ 32,681 $ 33,773 $ (83,906 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – basic $ 6.43 $ 1.42 $ 8.36 $ 4.78 $ 0.83 $ 0.82 $ 0.77 $ (2.10 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – diluted $ 6.43 $ 1.42 $ 8.35 $ 4.78 $ 0.83 $ 0.82 $ 0.77 $ (2.10 ) Average shares outstanding – basic 42,065 39,552 43,483 39,641 43,462 39,624 43,467 40,111 Average shares outstanding – diluted 42,091 39,599 43,521 39,654 43,537 39,637 43,552 40,111

Condensed Consolidating Finan_2

Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2019
Condensed Consolidating Financial Information Provided In Connection With Outstanding Debt Of Subsidiaries [Abstract]
Condensed Consolidating Balance Sheet	Condensed Consolidating Balance Sheet at December 31, 2019 RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Assets Total investments $ 190,451 $ 123,792 $ 288,137 $ 16,766,409 $ — $ 17,368,789 Cash and cash equivalents 26,460 9,440 8,731 1,334,437 — 1,379,068 Investments in subsidiaries 5,204,260 48,247 1,426,838 — (6,679,345 ) — Due from subsidiaries and affiliates 10,725 101,579 — — (112,304 ) — Premiums receivable — — — 2,599,896 — 2,599,896 Prepaid reinsurance premiums — — — 767,781 — 767,781 Reinsurance recoverable — — — 2,791,297 — 2,791,297 Accrued investment income — 270 1,171 71,020 — 72,461 Deferred acquisition costs and value of business acquired — — — 663,991 — 663,991 Receivable for investments sold 173 — — 78,196 — 78,369 Other assets 847,406 10,978 12,211 301,578 (825,957 ) 346,216 Goodwill and other intangible assets 116,212 — — 146,014 — 262,226 Total assets $ 6,395,687 $ 294,306 $ 1,737,088 $ 25,520,619 $ (7,617,606 ) $ 26,330,094 Liabilities, Noncontrolling Interests and Shareholders’ Equity Liabilities Reserve for claims and claim expenses $ — $ — $ — $ 9,384,349 $ — $ 9,384,349 Unearned premiums — — — 2,530,975 — 2,530,975 Debt 391,475 — 970,255 148,349 (125,974 ) 1,384,105 Amounts due to subsidiaries and affiliates 6,708 51 102,493 — (109,252 ) — Reinsurance balances payable — — — 2,830,691 — 2,830,691 Payable for investments purchased — — — 225,275 — 225,275 Other liabilities 26,137 278 14,162 899,682 (8,235 ) 932,024 Total liabilities 424,320 329 1,086,910 16,019,321 (243,461 ) 17,287,419 Redeemable noncontrolling interests — — — 3,071,308 — 3,071,308 Shareholders’ Equity Total shareholders’ equity 5,971,367 293,977 650,178 6,429,990 (7,374,145 ) 5,971,367 Total liabilities, noncontrolling interests and shareholders’ equity $ 6,395,687 $ 294,306 $ 1,737,088 $ 25,520,619 $ (7,617,606 ) $ 26,330,094 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Balance Sheet at December 31, 2018 RenaissanceRe Holdings Ltd. (Parent Guarantor) RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) Consolidating Adjustments (2) RenaissanceRe Consolidated Assets Total investments $ 313,360 $ 77,842 $ 28,885 $ 11,465,660 $ — $ 11,885,747 Cash and cash equivalents 3,534 3,350 9,604 1,091,434 — 1,107,922 Investments in subsidiaries 4,414,475 58,458 1,215,663 — (5,688,596 ) — Due from subsidiaries and affiliates 57,039 101,579 — — (158,618 ) — Premiums receivable — — — 1,537,188 — 1,537,188 Prepaid reinsurance premiums — — — 616,185 — 616,185 Reinsurance recoverable — — — 2,372,221 — 2,372,221 Accrued investment income 1,046 310 127 49,828 — 51,311 Deferred acquisition costs — — — 476,661 — 476,661 Receivable for investments sold 203 23,885 — 232,328 — 256,416 Other assets 458,842 22,571 313,636 (1,403,636 ) 743,714 135,127 Goodwill and other intangible assets 120,476 — — 116,942 — 237,418 Total assets $ 5,368,975 $ 287,995 $ 1,567,915 $ 16,554,811 $ (5,103,500 ) $ 18,676,196 Liabilities, Redeemable Noncontrolling Interest and Shareholders’ Equity Liabilities Reserve for claims and claim expenses $ — $ — $ — $ 6,076,271 $ — $ 6,076,271 Unearned premiums — — — 1,716,021 — 1,716,021 Debt 300,000 — 843,086 148,041 (300,000 ) 991,127 Amounts due to subsidiaries and affiliates 6,453 217 102,243 — (108,913 ) — Reinsurance balances payable — — — 1,902,056 — 1,902,056 Payable for investments purchased — 24 — 380,308 — 380,332 Other liabilities 17,442 5,362 13,918 482,422 (5,535 ) 513,609 Total liabilities 323,895 5,603 959,247 10,705,119 (414,448 ) 11,579,416 Redeemable noncontrolling interests — — — 2,051,700 — 2,051,700 Shareholders’ Equity Total shareholders’ equity 5,045,080 282,392 608,668 3,797,992 (4,689,052 ) 5,045,080 Total liabilities, redeemable noncontrolling interest and shareholders’ equity $ 5,368,975 $ 287,995 $ 1,567,915 $ 16,554,811 $ (5,103,500 ) $ 18,676,196 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments.
Condensed Consolidating Statement of Operations	Condensed Consolidating Statement of Operations RenaissanceRe Holdings Ltd. (Parent Guarantor) RenRe North America Holdings Inc. (Subsidiary Issuer) Platinum RenaissanceRe Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) Consolidating Adjustments (2) RenaissanceRe Consolidated Revenues Net premiums earned $ — $ — $ — $ — $ 1,717,575 $ — $ 1,717,575 Net investment income 23,109 1,947 1,373 3,090 219,490 (26,800 ) 222,209 Net foreign exchange (losses) gains (1 ) — — — 10,629 — 10,628 Equity in (losses) earnings of other ventures — — — (223 ) 8,253 — 8,030 Other income — — — — 9,415 — 9,415 Net realized and unrealized (losses) gains on investments (1,357 ) 9,621 4,916 (479 ) 123,121 — 135,822 Total revenues 21,751 11,568 6,289 2,388 2,088,483 (26,800 ) 2,103,679 Expenses Net claims and claim expenses incurred — — — — 1,861,428 — 1,861,428 Acquisition expenses — — — — 346,892 — 346,892 Operational expenses 11,314 103 85 26,063 141,572 (18,359 ) 160,778 Corporate expenses 18,546 — — — 26 — 18,572 Interest expense 1,572 — 2,461 31,657 10,075 (1,572 ) 44,193 Total expenses 31,432 103 2,546 57,720 2,359,993 (19,931 ) 2,431,863 (Loss) income before equity in net (loss) income of subsidiaries and taxes (9,681 ) 11,465 3,743 (55,332 ) (271,510 ) (6,869 ) (328,184 ) Equity in net (loss) income of subsidiaries (212,708 ) 756 28,028 9,298 — 174,626 — (Loss) income before taxes (222,389 ) 12,221 31,771 (46,034 ) (271,510 ) 167,757 (328,184 ) Income tax (expense) benefit — (18,147 ) (1,175 ) 7,163 (14,328 ) — (26,487 ) Net (loss) income (222,389 ) (5,926 ) 30,596 (38,871 ) (285,838 ) 167,757 (354,671 ) Net loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Net (loss) income attributable to RenaissanceRe (222,389 ) (5,926 ) 30,596 (38,871 ) (153,556 ) 167,757 (222,389 ) Dividends on preference shares (22,381 ) — — — — — (22,381 ) Net (loss) income (attributable) available to RenaissanceRe common shareholders $ (244,770 ) $ (5,926 ) $ 30,596 $ (38,871 ) $ (153,556 ) $ 167,757 $ (244,770 ) (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Comprehensive Income (Loss) for the year ended December 31, 2017 RenaissanceRe Holdings Ltd. (Parent Guarantor) RenRe North America Holdings Inc. (Subsidiary Issuer) Platinum RenaissanceRe Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) Consolidating Adjustments (2) RenaissanceRe Consolidated Comprehensive (loss) income Net (loss) income $ (222,389 ) $ (5,926 ) $ 30,596 $ (38,871 ) $ (285,838 ) $ 167,757 $ (354,671 ) Change in net unrealized gains on investments, net of tax (909 ) (89 ) — (89 ) — 178 (909 ) Comprehensive (loss) income (223,298 ) (6,015 ) 30,596 (38,960 ) (285,838 ) 167,935 (355,580 ) Net loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Comprehensive loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Comprehensive (loss) income (attributable) available to RenaissanceRe $ (223,298 ) $ (6,015 ) $ 30,596 $ (38,960 ) $ (153,556 ) $ 167,935 $ (223,298 ) Condensed Consolidating Statement of Operations for the year ended December 31, 2018 RenaissanceRe RenRe North Inc. RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Revenues Net premiums earned $ — $ — $ — $ 1,976,129 $ — $ 1,976,129 Net investment income 24,791 2,193 6,219 261,192 (32,529 ) 261,866 Net foreign exchange losses (3 ) — — (12,425 ) — (12,428 ) Equity in earnings of other ventures — — 3,065 15,409 — 18,474 Other income — — — 5,969 — 5,969 Net realized and unrealized gains (losses) on investments 633 (4,360 ) (329 ) (171,013 ) — (175,069 ) Total revenues 25,421 (2,167 ) 8,955 2,075,261 (32,529 ) 2,074,941 Expenses Net claims and claim expenses incurred — — — 1,120,018 — 1,120,018 Acquisition expenses — — — 432,989 — 432,989 Operational expenses 7,679 110 34,534 164,605 (28,661 ) 178,267 Corporate expenses 25,190 — 7 3,103 5,683 33,983 Interest expense 5,683 — 37,019 4,367 — 47,069 Total expenses 38,552 110 71,560 1,725,082 (22,978 ) 1,812,326 (Loss) income before equity in net income (loss) of subsidiaries and taxes (13,131 ) (2,277 ) (62,605 ) 350,179 (9,551 ) 262,615 Equity in net income (loss) of subsidiaries 240,495 5,631 9,091 — (255,217 ) — Income (loss) before taxes 227,364 3,354 (53,514 ) 350,179 (264,768 ) 262,615 Income tax benefit (expense) — 582 6,119 (399 ) — 6,302 Net income (loss) 227,364 3,936 (47,395 ) 349,780 (264,768 ) 268,917 Net income attributable to redeemable noncontrolling interests — — — (41,553 ) — (41,553 ) Net income (loss) attributable to RenaissanceRe 227,364 3,936 (47,395 ) 308,227 (264,768 ) 227,364 Dividends on preference shares (30,088 ) — — — — (30,088 ) Net income (loss) available (attributable) to RenaissanceRe common shareholders $ 197,276 $ 3,936 $ (47,395 ) $ 308,227 $ (264,768 ) $ 197,276 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Operations for RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Revenues Net premiums earned $ — $ — $ — $ 3,338,403 $ — $ 3,338,403 Net investment income 39,629 2,318 7,547 419,502 (45,163 ) 423,833 Net foreign exchange gains (losses) 7,342 — — (10,280 ) — (2,938 ) Equity in earnings of other ventures — — 3,886 19,338 — 23,224 Other income — — — 4,949 — 4,949 Net realized and unrealized gains on investments 12,393 21,557 151 380,382 — 414,483 Total revenues 59,364 23,875 11,584 4,152,294 (45,163 ) 4,201,954 Expenses Net claims and claim expenses incurred — — — 2,097,021 — 2,097,021 Acquisition expenses — — — 762,232 — 762,232 Operational expenses 7,506 56 38,487 207,981 (31,297 ) 222,733 Corporate expenses 58,393 — 16 43,413 (7,700 ) 94,122 Interest expense 18,086 — 37,993 2,285 — 58,364 Total expenses 83,985 56 76,496 3,112,932 (38,997 ) 3,234,472 (Loss) income before equity in net income of subsidiaries and taxes (24,621 ) 23,819 (64,912 ) 1,039,362 (6,166 ) 967,482 Equity in net income of subsidiaries 773,419 5,611 99,148 — (878,178 ) — Income before taxes 748,798 29,430 34,236 1,039,362 (884,344 ) 967,482 Income tax (expense) benefit — (4,872 ) 6,510 (18,853 ) — (17,215 ) Net income 748,798 24,558 40,746 1,020,509 (884,344 ) 950,267 Net income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Net income attributable to RenaissanceRe 748,798 24,558 40,746 819,040 (884,344 ) 748,798 Dividends on preference shares (36,756 ) — — — — (36,756 ) Net income available to RenaissanceRe common shareholders $ 712,042 $ 24,558 $ 40,746 $ 819,040 $ (884,344 ) $ 712,042 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Comprehensive Income for the year ended December 31, 2019 RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Comprehensive income Net income $ 748,798 $ 24,558 $ 40,746 $ 1,020,509 $ (884,344 ) $ 950,267 Change in net unrealized gains on investments, net of tax 2,173 528 764 — (1,292 ) 2,173 Foreign currency translation adjustments, net of tax (2,679 ) — — — — (2,679 ) Comprehensive income 748,292 25,086 41,510 1,020,509 (885,636 ) 949,761 Net income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Comprehensive income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Comprehensive income available to RenaissanceRe $ 748,292 $ 25,086 $ 41,510 $ 819,040 $ (885,636 ) $ 748,292
Condensed Consolidating Statement of Comprehensive Income	Condensed Consolidating Statement of Comprehensive Income (Loss) for the year ended December 31, 2018 RenaissanceRe RenRe North Inc. RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Comprehensive income (loss) Net income (loss) $ 227,364 $ 3,936 $ (47,395 ) $ 349,780 $ (264,768 ) $ 268,917 Change in net unrealized gains on investments, net of tax (1,657 ) (160 ) (162 ) — 322 (1,657 ) Comprehensive income (loss) 225,707 3,776 (47,557 ) 349,780 (264,446 ) 267,260 Net income attributable to redeemable noncontrolling interests — — — (41,553 ) — (41,553 ) Comprehensive income attributable to redeemable noncontrolling interests — — — (41,553 ) — (41,553 ) Comprehensive income (loss) available (attributable) to RenaissanceRe $ 225,707 $ 3,776 $ (47,557 ) $ 308,227 $ (264,446 ) $ 225,707 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Comprehensive Income for the year ended December 31, 2019 RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other Consolidating RenaissanceRe Comprehensive income Net income $ 748,798 $ 24,558 $ 40,746 $ 1,020,509 $ (884,344 ) $ 950,267 Change in net unrealized gains on investments, net of tax 2,173 528 764 — (1,292 ) 2,173 Foreign currency translation adjustments, net of tax (2,679 ) — — — — (2,679 ) Comprehensive income 748,292 25,086 41,510 1,020,509 (885,636 ) 949,761 Net income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Comprehensive income attributable to redeemable noncontrolling interests — — — (201,469 ) — (201,469 ) Comprehensive income available to RenaissanceRe $ 748,292 $ 25,086 $ 41,510 $ 819,040 $ (885,636 ) $ 748,292 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor, Subsidiary Guarantor and Subsidiary Issuer consolidating adjustments. Condensed Consolidating Statement of Comprehensive Income (Loss) for the year ended December 31, 2017 RenaissanceRe Holdings Ltd. (Parent Guarantor) RenRe North America Holdings Inc. (Subsidiary Issuer) Platinum RenaissanceRe Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) Consolidating Adjustments (2) RenaissanceRe Consolidated Comprehensive (loss) income Net (loss) income $ (222,389 ) $ (5,926 ) $ 30,596 $ (38,871 ) $ (285,838 ) $ 167,757 $ (354,671 ) Change in net unrealized gains on investments, net of tax (909 ) (89 ) — (89 ) — 178 (909 ) Comprehensive (loss) income (223,298 ) (6,015 ) 30,596 (38,960 ) (285,838 ) 167,935 (355,580 ) Net loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Comprehensive loss attributable to redeemable noncontrolling interests — — — — 132,282 — 132,282 Comprehensive (loss) income (attributable) available to RenaissanceRe $ (223,298 ) $ (6,015 ) $ 30,596 $ (38,960 ) $ (153,556 ) $ 167,935 $ (223,298 ) (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. (2) Includes Parent Guarantor and Subsidiary Issuer consolidating adjustments.
Condensed Consolidating Statement of Cash Flows	Condensed Consolidating Statement of Cash Flows for the year ended December 31, 2019 RenaissanceRe RenRe North RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Consolidated Cash flows (used in) provided by operating activities Net cash (used in) provided by operating activities $ (2,861 ) $ 3,872 $ 366,934 $ 1,769,250 $ 2,137,195 Cash flows provided by (used in) investing activities Proceeds from sales and maturities of fixed maturity investments trading 306,579 77,798 60,737 16,868,826 17,313,940 Purchases of fixed maturity investments trading (66,740 ) (77,145 ) (33,577 ) (17,741,881 ) (17,919,343 ) Net purchases of equity investments trading — (3,358 ) — (4,483 ) (7,841 ) Net (purchases) sales of short term investments (116,499 ) 739 (283,717 ) (1,501,264 ) (1,900,741 ) Net purchases of other investments — — — (202,878 ) (202,878 ) Net purchases of investments in other ventures — — — (2,717 ) (2,717 ) Return of investment from investment in other ventures — — — 11,250 11,250 Net sales of other assets — — — (4,108 ) (4,108 ) Dividends and return of capital from subsidiaries 1,400,944 4,350 13,500 (1,418,794 ) — Contributions to subsidiaries (1,165,607 ) — (125,000 ) 1,290,607 — Due (from) to subsidiary (625,924 ) (166 ) 250 625,840 — Net purchase of TMR — — — (276,206 ) (276,206 ) Net cash provided by (used in) investing activities (267,247 ) 2,218 (367,807 ) (2,355,808 ) (2,988,644 ) Cash flows provided by financing activities Dividends paid – RenaissanceRe common shares (59,368 ) — — — (59,368 ) Dividends paid – preference shares (36,756 ) — — — (36,756 ) Issuance of debt, net of expenses 396,411 — — — 396,411 Net third-party redeemable noncontrolling interest share transactions — — — 827,083 827,083 Taxes paid on withholding shares (7,253 ) — — — (7,253 ) Net cash provided by financing activities 293,034 — — 827,083 1,120,117 Effect of exchange rate changes on foreign currency cash — — — 2,478 2,478 Net increase (decrease) in cash and cash equivalents 22,926 6,090 (873 ) 243,003 271,146 Cash and cash equivalents, beginning of period 3,534 3,350 9,604 1,091,434 1,107,922 Cash and cash equivalents, end of period $ 26,460 $ 9,440 $ 8,731 $ 1,334,437 $ 1,379,068 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. Condensed Consolidating Statement of Cash Flows for the year ended December 31, 2018 RenaissanceRe RenRe North Inc. RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-guarantor Subsidiaries) (1) RenaissanceRe Consolidated Cash flows (used in) provided by operating activities Net cash (used in) provided by operating activities $ 17,187 $ 6,315 $ 62,645 $ 1,135,554 $ 1,221,701 Cash flows used in investing activities Proceeds from sales and maturities of fixed maturity investments trading 384,818 97,272 56,518 11,046,968 11,585,576 Purchases of fixed maturity investments trading (520,935 ) (72,292 ) (55,932 ) (11,840,813 ) (12,489,972 ) Net (purchases) sales of equity investments trading — (1,308 ) — 15,464 14,156 Net sales (purchases) of short term investments 48,600 (404 ) 455 (1,485,040 ) (1,436,389 ) Net purchases of other investments — — — (199,475 ) (199,475 ) Net purchases of investments in other ventures — — — (21,473 ) (21,473 ) Return of investment from investment in other ventures — — — 8,464 8,464 Net sales of other assets — — — 2,500 2,500 Dividends and return of capital from subsidiaries 672,098 — — (672,098 ) — Contributions to subsidiaries (785,785 ) (16,847 ) (65,000 ) 867,632 — Due to (from) subsidiaries (227,762 ) (9,525 ) 9,449 227,838 — Net cash used in investing activities (428,966 ) (3,104 ) (54,510 ) (2,050,033 ) (2,536,613 ) Cash flows provided by financing activities Dividends paid – RenaissanceRe common shares (52,841 ) — — — (52,841 ) Dividends paid – preference shares (30,088 ) — — — (30,088 ) RenaissanceRe common share issuance 250,000 — — — 250,000 Issuance of preference shares, net of expenses 241,448 — — — 241,448 Net third-party redeemable noncontrolling interest share transactions — — — 665,683 665,683 Taxes paid on withholding shares (7,862 ) — — — (7,862 ) Net cash provided by financing activities 400,657 — — 665,683 1,066,340 Effect of exchange rate changes on foreign currency cash — — — (5,098 ) (5,098 ) Net (decrease) increase in cash and cash equivalents (11,122 ) 3,211 8,135 (253,894 ) (253,670 ) Cash and cash equivalents, beginning of period 14,656 139 1,469 1,345,328 1,361,592 Cash and cash equivalents, end of period $ 3,534 $ 3,350 $ 9,604 $ 1,091,434 $ 1,107,922 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations. Condensed Consolidating Statement of Cash Flows for the year ended December 31, 2017 RenaissanceRe RenRe North Platinum Underwriters Finance, Inc. (Subsidiary Issuer) RenaissanceRe Finance, Inc. (Subsidiary Issuer) Other RenaissanceRe Cash flows (used in) provided by operating activities Net cash (used in) provided by operating activities $ 21,118 $ (8,253 ) $ (2,272 ) $ (347,890 ) $ 1,363,084 $ 1,025,787 Cash flows provided by (used in) investing activities Proceeds from sales and maturities of fixed maturity investments trading 261,601 100,248 289,741 288,900 8,550,179 9,490,669 Purchases of fixed maturity investments trading (344,463 ) (99,568 ) (143,991 ) (275,778 ) (9,229,732 ) (10,093,532 ) Net (purchases) sales of equity investments trading — (1,752 ) 85,324 — 32,265 115,837 Net sales (purchases) of short term investments 243,571 114 41,299 (493 ) 79,520 364,011 Net purchases of other investments — — — — (19,419 ) (19,419 ) Return of investment from investment in other ventures — — — — 20,000 20,000 Dividends and return of capital from subsidiaries 478,496 9,175 — 41,866 (529,537 ) — Contributions to subsidiaries (669,672 ) — (26,649 ) (9,890 ) 706,211 — Due to (from) subsidiary 294,419 13 (123 ) (509 ) (293,800 ) — Net cash provided by (used in) investing activities 263,952 8,230 245,601 44,096 (684,313 ) (122,434 ) Cash flows (used in) provided by financing activities Dividends paid – RenaissanceRe common shares (51,370 ) — — — — (51,370 ) Dividends paid – preference shares (22,381 ) — — — — (22,381 ) RenaissanceRe common share repurchases (188,591 ) — — — — (188,591 ) Net repayment of debt — — (250,000 ) — — (250,000 ) Issuance of debt, net of expenses — — — 295,866 — 295,866 Net third-party redeemable noncontrolling interest share transactions — — — — 260,475 260,475 Taxes paid on withholding shares (15,139 ) — — — — (15,139 ) Net cash (used in) provided by financing activities (277,481 ) — (250,000 ) 295,866 260,475 28,860 Effect of exchange rate changes on foreign currency cash — — — — 8,222 8,222 Net increase (decrease) in cash and cash equivalents 7,589 (23 ) (6,671 ) (7,928 ) 947,468 940,435 Cash and cash equivalents, beginning of year 7,067 162 6,671 9,397 397,860 421,157 Cash and cash equivalents, end of year $ 14,656 $ 139 $ — $ 1,469 $ 1,345,328 $ 1,361,592 (1) Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations.

Organization (Details)

Organization (Details)	12 Months Ended
	Dec. 31, 2019
RenaissanceRe Upsilon Fund Ltd | Not Primary Beneficiary
Variable Interest Entity [Line Items]
Percent of segregated funds owned by third party investors	100.00%

Significant Accounting Polici_3

Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
VOBA asset, amortization period	2 years
Decrease in cash inflows from cash flows provided by operating activities	$ (2,137,195)	$ (1,221,701)	$ (1,025,787)
Increase in cash flows used in investing activities	$ (2,988,644)	$ (2,536,613)	(122,434)
Accounting Standards Update 2016-15
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Decrease in cash inflows from cash flows provided by operating activities			20,000
Increase in cash flows used in investing activities			$ 20,000
Retained earnings | Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of adoption of new accounting principle in period of adoption				$ 2,213

Acquisition of Tokio Millenni_3

Acquisition of Tokio Millennium Re (Overview) (Details) - TMR - USD ($) $ in Thousands	Mar. 22, 2019	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Total purchase price	$ 1,563,593
Corporate expenses associated with the acquisition		$ 49,700	$ 3,400

Acquisition of Tokio Millenni_4

Acquisition of Tokio Millennium Re (Schedule of Purchase Price) (Details) - TMR - USD ($) $ / shares in Units, $ in Thousands	Mar. 22, 2019	Mar. 15, 2019
Business Acquisition [Line Items]
Special Dividend paid to common shareholders of Tokio and holders of Tokio equity awards	$ 500,000
Shares issued (in shares)	1,739,071
Common share price of RenaissanceRe (in dollars per share)	$ 143.75	$ 143.7539
Market value of RenaissanceRe common shares issued by RenaissanceRe to Tokio	$ 249,998
Cash consideration paid by RenaissanceRe as acquisition consideration	813,595
Total purchase price	1,563,593
Less: Special Dividend paid to Tokio	(500,000)
Net purchase price	$ 1,063,593
Common share price, trading volume, term		30 days

Acquisition of Tokio Millenni_5

Acquisition of Tokio Millennium Re (Fair Value of Net Assets Acquired and Liabilities Assumed) (Details) - TMR $ in Thousands	Mar. 22, 2019USD ($)state
Business Acquisition [Line Items]
Excess purchase price over the fair value of net assets acquired assigned to goodwill	$ 13,094
Acquired finite-lived intangibles, weighted average amortization period	10 years 6 months
Value of business acquired, amortization period	2 years
Value of business acquired	$ 287,600
Deferred tax liability related to the estimated fair value of the intangible assets recorded	2,281
Deferred tax liability related to other adjustments	2,606
Insurance licenses
Business Acquisition [Line Items]
Identifiable indefinite lived intangible assets (insurance licenses)	$ 6,800
Number of states, ability to write reinsurance | state	50

Acquisition of Tokio Millenni_6

Acquisition of Tokio Millennium Re (Schedule of Fair Value of Net Assets Acquired and Liabilities Assumed) (Details) - TMR - USD ($) $ in Thousands	Mar. 22, 2019	Dec. 31, 2019
Business Acquisition [Line Items]
Shareholders’ equity of TMR at March 22, 2019	$ 1,032,961
Adjustments for fair value, by applicable balance sheet caption:
Net deferred acquisition costs and value of business acquired	(56,788)
Net reserve for claims and claim expenses	67,782
Goodwill and intangible assets at March 22, 2019 of TMR	(6,569)
Total adjustments for fair value by applicable balance sheet caption before tax impact	4,425
Other assets - net deferred tax liability related to fair value adjustments and value of business acquired	(2,606)
Total adjustments for fair value by applicable balance sheet caption, net of tax	1,819
Adjustments for fair value of the identifiable intangible assets:
Identifiable intangible assets before tax impact	18,000	$ 17,190
Other assets - deferred tax liability on identifiable intangible assets	(2,281)
Total adjustments for fair value of the identifiable intangible assets and value of business acquired, net of tax	15,719
Total adjustments for fair value by applicable balance sheet caption, identifiable intangible assets and value of business acquired, net of tax	17,538
Shareholders’ equity of TMR at fair value	1,050,499
Total net purchase price paid by RenaissanceRe	1,063,593
Excess purchase price over the fair value of net assets acquired assigned to goodwill	13,094
Insurance licenses
Adjustments for fair value of the identifiable intangible assets:
Identifiable indefinite lived intangible assets (insurance licenses)	6,800
Top Broker Relationships and Renewal Rights
Adjustments for fair value of the identifiable intangible assets:
Identifiable finite lived intangible assets (top broker relationships and renewal rights)	$ 11,200

Acquisition of Tokio Millenni_7

Acquisition of Tokio Millennium Re (Schedule of Identifiable Intangible Assets) (Details) - TMR - USD ($) $ in Thousands	Mar. 22, 2019	Dec. 31, 2019
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Intangible Assets, Other Than Goodwill [Roll Forward]
Accumulated amortization (from March 22, 2019 through December 31, 2019)		$ 810
Net identifiable intangible assets related to the acquisition of TMR at December 31, 2019	$ 18,000	$ 17,190
Economic Useful Life	10 years 6 months
Insurance licenses
Business Acquisition [Line Items]
Intangible assets acquired	$ 6,800
Top broker relationships
Business Acquisition [Line Items]
Identifiable finite lived intangible assets (top broker relationships and renewal rights)	$ 10,000
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Intangible Assets, Other Than Goodwill [Roll Forward]
Economic Useful Life	10 years
Renewal rights
Business Acquisition [Line Items]
Identifiable finite lived intangible assets (top broker relationships and renewal rights)	$ 1,200
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Intangible Assets, Other Than Goodwill [Roll Forward]
Economic Useful Life	15 years

Acquisition of Tokio Millenni_8

Acquisition of Tokio Millennium Re (Schedule of Financial Results) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Total revenues	$ 1,105,305	$ 1,051,148	$ 1,238,380	$ 807,121	$ 547,997	$ 629,754	$ 479,204	$ 417,986	$ 4,201,954	$ 2,074,941	$ 2,103,679
Net income (loss) available (attributable) to RenaissanceRe common shareholders	$ 33,773	$ 36,698	$ 367,854	$ 273,717	$ (83,906)	$ 32,681	$ 191,788	$ 56,713	712,042	197,276	$ (244,770)
TMR
Business Acquisition [Line Items]
Total revenues									922,727
Net income (loss) available (attributable) to RenaissanceRe common shareholders									99,169
Corporate expenses associated with the acquisition									$ 49,700	$ 3,400

Acquisition of Tokio Millenni_9

Acquisition of Tokio Millennium Re (Taxation) (Details) - TMR $ in Millions	Mar. 22, 2019USD ($)
Business Acquisition [Line Items]
Other assets - net deferred tax liability related to fair value adjustments and value of business acquired	$ 5.7
Deferred tax assets, valuation allowance	$ 35.7

Acquisition of Tokio Millenn_10

Acquisition of Tokio Millennium Re (Schedule of Supplemental Pro Forma Information) (Details) - TMR - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Total revenues	$ 4,542,979	$ 3,338,903
Net income available to RenaissanceRe common shareholders	$ 768,719	$ 281,974

Acquisition of Tokio Millenn_11

Acquisition of Tokio Millennium Re (Defined Benefit Pension Plan) (Details) - Pension Plan - TMR $ in Millions	Dec. 31, 2019USD ($)
Business Acquisition [Line Items]
Net balance sheet liability	$ 6.5
Projected benefit obligation	20.4
Plan assets at fair value	$ 13.9

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets (Schedule of Intangible Assets and Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019
Other intangible assets
Gross amount	$ 159,503		$ 177,507
Accumulated impairment losses and amortization	(102,537)		(111,639)
Intangible Assets, Net, Excluding Goodwill [Roll Forward]
Other intangible assets, net, ending balance	56,966
Intangible Assets, Net, Including Goodwill [Roll Forward]
Goodwill and Other intangible assets, net, ending balance	237,418
Excluding Equity Method Investments
Goodwill
Gross amount	199,889	$ 199,889	212,983
Accumulated impairment losses and amortization	(2,299)	(2,299)	(2,299)
Acquired during the year	13,094
Goodwill	197,590	197,590	210,684
Other intangible assets
Gross amount	96,599	96,599	114,599
Accumulated impairment losses and amortization	(56,771)	(51,044)	(63,057)
Intangible Assets, Net, Excluding Goodwill [Roll Forward]
Other intangible assets, net, beginning balance	45,555
Acquired during the year	18,000
Amortization	(6,286)	(5,727)
Other intangible assets, net, ending balance	39,828	45,555
Goodwill and Other intangible assets, Total
Gross amount	296,488	296,488	327,582
Accumulated impairment losses and amortization	(59,070)	(53,343)	(65,356)
Intangible Assets, Net, Including Goodwill [Roll Forward]
Goodwill and Other intangible assets, net, beginning balance	243,145
Acquired during the year	31,094
Amortization	(6,286)	(5,727)
Goodwill and Other intangible assets, net, ending balance	237,418	243,145
Equity Method Investments
Goodwill
Gross amount	15,098	12,318	15,098
Accumulated impairment losses and amortization	(4,500)	(4,500)	(4,500)
Acquired during the year	0	2,780
Goodwill	10,598	7,818	10,598
Other intangible assets
Gross amount	62,904	51,796	62,908
Accumulated impairment losses and amortization	(45,766)	(42,880)	(48,582)
Intangible Assets, Net, Excluding Goodwill [Roll Forward]
Other intangible assets, net, beginning balance	8,916
Acquired during the year	4	11,108
Amortization	(2,816)	(2,886)
Other intangible assets, net, ending balance	17,138	8,916
Goodwill and Other intangible assets, Total
Gross amount	78,002	64,114	78,006
Accumulated impairment losses and amortization	(50,266)	(47,380)	$ (53,082)
Intangible Assets, Net, Including Goodwill [Roll Forward]
Goodwill and Other intangible assets, net, beginning balance	16,734
Acquired during the year	4	13,888
Amortization	(2,816)	(2,886)
Goodwill and Other intangible assets, net, ending balance	$ 27,736	$ 16,734

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Mar. 22, 2019	Dec. 31, 2018	Mar. 23, 2018	Dec. 31, 2017
Low
Goodwill and Intangible Assets [Line Items]
Finite-lived intangible assets, useful life	6 months
High
Goodwill and Intangible Assets [Line Items]
Finite-lived intangible assets, useful life	14 years 2 months 12 days
Weighted Average or Actual
Goodwill and Intangible Assets [Line Items]
Finite-lived intangible assets, useful life	7 years
Equity Method Investments
Goodwill and Intangible Assets [Line Items]
Goodwill	$ 10,598		$ 10,598		$ 7,818
Equity Method Investments | TMR
Goodwill and Intangible Assets [Line Items]
Goodwill		$ 13,100
Finite-lived intangible assets		11,200
Indefinite-lived intangible assets		$ 6,800
Equity Method Investments | TWFG Holding Company LLC
Goodwill and Intangible Assets [Line Items]
Goodwill				$ 2,800
Finite-lived intangible assets				2,000
Indefinite-lived intangible assets				$ 9,100

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets (Schedule of Goodwill and Other Intangible Assets Included in Equity Method Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019
Other intangible assets
Gross amount	$ 159,503		$ 177,507
Accumulated impairment losses and amortization	(102,537)		(111,639)
Intangible Assets, Net, Excluding Goodwill [Roll Forward]
Other intangible assets, net, ending balance	56,966
Intangible Assets, Net, Including Goodwill [Roll Forward]
Goodwill and Other intangible assets, net, ending balance	237,418
Investments in other ventures, under equity method
Goodwill
Gross amount	15,098	$ 12,318	15,098
Accumulated impairment losses and amortization	(4,500)	(4,500)	(4,500)
Goodwill	10,598	7,818	10,598
Acquired during the year	0	2,780
Other intangible assets
Gross amount	62,904	51,796	62,908
Accumulated impairment losses and amortization	(45,766)	(42,880)	(48,582)
Intangible Assets, Net, Excluding Goodwill [Roll Forward]
Other intangible assets, net, beginning balance	8,916
Acquired during the year	4	11,108
Amortization	(2,816)	(2,886)
Other intangible assets, net, ending balance	17,138	8,916
Goodwill and Other intangible assets, Total
Gross amount	78,002	64,114	78,006
Accumulated impairment losses and amortization	(50,266)	(47,380)	$ (53,082)
Intangible Assets, Net, Including Goodwill [Roll Forward]
Goodwill and Other intangible assets, net, beginning balance	16,734
Acquired during the year	4	13,888
Amortization	(2,816)	(2,886)
Goodwill and Other intangible assets, net, ending balance	$ 27,736	$ 16,734

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets (Schedule of Finite-Lived Intangible Assets by Major Class) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	$ 177,507	$ 159,503
Accumulated amortization and impairment losses	(111,639)	(102,537)
Other intangible assets, net	65,868	56,966
Licenses
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	26,186	19,414
Accumulated amortization and impairment losses	0	0
Other intangible assets, net	26,186	19,414
Customer relationships and customer lists
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	108,651	97,419
Accumulated amortization and impairment losses	(69,298)	(60,221)
Other intangible assets, net	39,353	37,198
Value of business acquired
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	20,200	20,200
Accumulated amortization and impairment losses	(20,200)	(20,200)
Other intangible assets, net	0	0
Software
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	12,230	12,230
Accumulated amortization and impairment losses	(12,230)	(12,230)
Other intangible assets, net	0	0
Patents and intellectual property
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	4,500	4,500
Accumulated amortization and impairment losses	(4,500)	(4,500)
Other intangible assets, net	0	0
Covenants not-to-compete
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	4,030	4,030
Accumulated amortization and impairment losses	(4,030)	(4,030)
Other intangible assets, net	0	0
Trademarks and trade names
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Gross carrying value	1,710	1,710
Accumulated amortization and impairment losses	(1,381)	(1,356)
Other intangible assets, net	$ 329	$ 354

Goodwill and Other Intangible_7

Goodwill and Other Intangible Assets (Schedule of Expected Impairment Charges and Amortization Expense) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Other intangible assets
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Total	$ 65,868
Other intangible assets | Other intangible assets
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Total	51,542
Other intangible assets | Investments in other ventures, under equity method
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Total	14,326
Other intangible assets
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Indefinite lived	26,186
Other intangible assets | Other intangible assets
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Indefinite lived	17,039
Other intangible assets | Investments in other ventures, under equity method
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
Indefinite lived	9,147
Other intangible assets
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
2020	8,272
2021	7,085
2022	6,697
2023	5,804
2024	4,910
2024 and thereafter	6,914
Total remaining amortization expense	39,682
Other intangible assets | Other intangible assets
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
2020	6,317
2021	5,990
2022	5,602
2023	5,173
2024	4,716
2024 and thereafter	6,705
Total remaining amortization expense	34,503
Other intangible assets | Investments in other ventures, under equity method
Schedule of Finite and Indefinite-lived Intangible Assets [Line Items]
2020	1,955
2021	1,095
2022	1,095
2023	631
2024	194
2024 and thereafter	209
Total remaining amortization expense	$ 5,179

Investments (Schedule of Fair V

Investments (Schedule of Fair Value of Fixed Maturity Investments Trading) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Investment [Line Items]
Fixed maturity investments	$ 11,171,655	$ 8,088,870
U.S. treasuries
Investment [Line Items]
Fixed maturity investments	4,467,345	3,331,411
Agencies
Investment [Line Items]
Fixed maturity investments	343,031	174,883
Municipal
Investment [Line Items]
Fixed maturity investments	0	6,854
Non-U.S. government
Investment [Line Items]
Fixed maturity investments	497,392	279,818
Non-U.S. government-backed corporate
Investment [Line Items]
Fixed maturity investments	321,356	160,063
Corporate
Investment [Line Items]
Fixed maturity investments	3,075,660	2,450,244
Agency mortgage-backed
Investment [Line Items]
Fixed maturity investments	1,148,499	817,880
Non-agency mortgage-backed
Investment [Line Items]
Fixed maturity investments	294,604	278,680
Commercial mortgage-backed
Investment [Line Items]
Fixed maturity investments	468,698	282,294
Asset-backed
Investment [Line Items]
Fixed maturity investments	$ 555,070	$ 306,743

Investments (Schedule of Contra

Investments (Schedule of Contractual Maturities of Fixed Maturity Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amortized Cost
Due in less than one year	$ 543,687
Due after one through five years	5,467,501
Due after five through ten years	2,386,467
Due after ten years	211,424
Fixed maturity investments trading	11,067,414	$ 8,163,962
Debt Securities, Trading, and Equity Securities, FV-NI [Abstract]
Due in less than one year	544,636
Due after one through five years	5,522,769
Due after five through ten years	2,420,602
Due after ten years	216,777
Fixed maturity investments trading	11,171,655	8,088,870
Mortgage-backed
Amortized Cost
Fixed maturity investments trading	1,902,365
Debt Securities, Trading, and Equity Securities, FV-NI [Abstract]
Fixed maturity investments trading	1,911,801
Asset-backed
Amortized Cost
Fixed maturity investments trading	555,970
Debt Securities, Trading, and Equity Securities, FV-NI [Abstract]
Fixed maturity investments trading	$ 555,070	$ 306,743

Investments (Schedule of Fair_2

Investments (Schedule of Fair Value of Equity Investments Trading) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Investment [Line Items]
Equity investments trading	$ 436,931	$ 310,252
Financials
Investment [Line Items]
Equity investments trading	248,189	200,357
Communications and technology
Investment [Line Items]
Equity investments trading	79,206	42,333
Industrial, utilities and energy
Investment [Line Items]
Equity investments trading	38,583	24,520
Consumer
Investment [Line Items]
Equity investments trading	35,987	20,639
Healthcare
Investment [Line Items]
Equity investments trading	29,510	18,925
Basic materials
Investment [Line Items]
Equity investments trading	$ 5,456	$ 3,478

Investments (Pledged Investment

Investments (Pledged Investments and Reverse Repurchase Agreements) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Investments [Abstract]
Cash and investments at fair value on deposit with, or in trust accounts for the benefit of, various counterparties	$ 7,000	$ 5,700
Cash and investments at fair value on deposit with, or in trust accounts for the benefit of, U.S. state regulatory authorities	2,000	2,000
Reverse repurchase agreements	$ 57.6	$ 3.7
Minimum percentage of collateral required	102.00%

Investments (Schedule of Net In

Investments (Schedule of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net Investment Income [Line Items]
Gross investment income									$ 441,478	$ 276,780	$ 237,596
Investment expenses									(17,645)	(14,914)	(15,387)
Net investment income	$ 112,695	$ 113,844	$ 115,832	$ 81,462	$ 53,338	$ 80,696	$ 71,356	$ 56,476	423,833	261,866	222,209
Fixed maturity investments
Net Investment Income [Line Items]
Gross investment income									318,503	211,973	179,624
Short term investments
Net Investment Income [Line Items]
Gross investment income									56,264	33,571	11,082
Equity investments
Net Investment Income [Line Items]
Gross investment income									4,808	4,474	3,628
Private equity investments
Net Investment Income [Line Items]
Gross investment income									14,981	477	33,999
Other
Net Investment Income [Line Items]
Gross investment income									39,246	22,475	8,067
Cash and cash equivalents
Net Investment Income [Line Items]
Gross investment income									$ 7,676	$ 3,810	$ 1,196

Investments (Schedule of Net Re

Investments (Schedule of Net Realized and Unrealized Gains (Losses) on Investments) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Gain (Loss) on Securities [Line Items]
Net realized and unrealized gains (losses) on equity investments trading									$ 95,149	$ (39,161)	$ 119,544
Net realized and unrealized gains (losses) on investments	$ 17,897	$ 31,938	$ 194,003	$ 170,645	$ (88,654)	$ 13,630	$ (17,901)	$ (82,144)	414,483	(175,069)	135,822
Fixed maturity investments
Gain (Loss) on Securities [Line Items]
Gross realized gains									133,409	21,284	49,121
Gross realized losses									(43,149)	(91,098)	(38,832)
Net realized gains (losses) on fixed maturity investments									90,260	(69,814)	10,289
Net unrealized gains (losses) on fixed maturity investments trading									170,183	(57,310)	8,479
Investments-related derivatives
Gain (Loss) on Securities [Line Items]
Net realized and unrealized gains (losses) on investments-related derivatives									58,891	(8,784)	(2,490)
Equity investments
Gain (Loss) on Securities [Line Items]
Net realized gains on equity investments trading sold during the period									31,062	27,739	80,027
Net unrealized gains (losses) on equity investments trading still held at reporting date									$ 64,087		$ 39,517
Net unrealized gains (losses) on equity investments trading still held at reporting date										$ (66,900)

Investments (Schedule of Other

Investments (Schedule of Other Investments) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Other investments	$ 1,087,377				$ 784,933				$ 1,087,377	$ 784,933
Net investment income	112,695	$ 113,844	$ 115,832	$ 81,462	53,338	$ 80,696	$ 71,356	$ 56,476	423,833	261,866	$ 222,209
Initial commitments	1,100,000								1,100,000
Fulfilled commitments	708,400								708,400
Unfunded commitments	411,300								411,300
Other investments
Schedule of Investments [Line Items]
Net investment income									54,200	23,000	42,100
Net unrealized gains recognized in earnings due to change in estimate									(5,500)	300	1,900
Other investments | Net investment income
Schedule of Investments [Line Items]
Net unrealized gains recognized in earnings									12,200	(8,300)	$ 24,700
Catastrophe bonds
Schedule of Investments [Line Items]
Other investments	781,641				516,571				781,641	516,571
Private equity investments
Schedule of Investments [Line Items]
Other investments	271,047				242,647				271,047	242,647
Senior secured bank loan funds
Schedule of Investments [Line Items]
Other investments	22,598				14,482				22,598	14,482
Hedge funds
Schedule of Investments [Line Items]
Other investments	$ 12,091				$ 11,233				$ 12,091	$ 11,233

Investments (Schedule of Invest

Investments (Schedule of Investments in Other Ventures, under Equity Method) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 106,549	$ 115,172
Tower Hill Companies
Schedule of Equity Method Investments [Line Items]
Ownership %	24.90%	24.90%
Carrying Value	$ 36,779	$ 38,241
Top Layer Re
Schedule of Equity Method Investments [Line Items]
Ownership %	50.00%	50.00%
Carrying Value	$ 35,363	$ 46,562
Other
Schedule of Equity Method Investments [Line Items]
Ownership %	26.60%	30.60%
Carrying Value	$ 34,407	$ 30,369

Investments (Schedule of Equity

Investments (Schedule of Equity in (Losses) Earnings of Other Ventures, Under Equity Method) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Equity in earnings of other ventures	$ 5,874	$ 5,877	$ 6,812	$ 4,661	$ 4,143	$ 7,648	$ 5,826	$ 857	$ 23,224	$ 18,474	$ 8,030
Equity method investment, dividends and distributions									(36,500)	(26,100)	29,700
Undistributed earnings (losses) from equity method investments	$ (800)				$ 3,800				(800)	3,800	(6,300)
Tower Hill Companies
Schedule of Equity Method Investments [Line Items]
Equity in earnings of other ventures									10,337	9,605	(1,647)
Top Layer Re
Schedule of Equity Method Investments [Line Items]
Equity in earnings of other ventures									8,801	8,852	9,851
Other
Schedule of Equity Method Investments [Line Items]
Equity in earnings of other ventures									$ 4,086	$ 17	$ (174)

Fair Value Measurements (Assets

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	$ 11,171,655,000	$ 8,088,870,000
Short term investments	4,566,277,000	2,586,520,000
Equity investments trading	436,931,000	310,252,000
Other investments	1,087,377,000	784,933,000
Other assets	32,944,000	4,968,000
Other liabilities	(28,213,000)	(13,327,000)
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	11,171,655,000	8,088,870,000
Short term investments	4,566,277,000	2,586,520,000
Equity investments trading	436,931,000	310,252,000
Other investments	1,087,377,000	784,933,000
Other assets	21,668,000	4,040,000
Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs	17,283,908,000	11,774,615,000
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	4,467,345,000	3,331,411,000
Short term investments	0	0
Equity investments trading	436,931,000	310,252,000
Other investments	0	0
Other assets		484,000
Other liabilities	(1,020,000)
Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs	4,903,256,000	3,642,147,000
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	6,704,310,000	4,757,459,000
Short term investments	4,566,277,000	2,586,520,000
Equity investments trading	0	0
Other investments	781,641,000	516,571,000
Other assets	17,957,000	11,915,000
Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs	12,070,185,000	7,872,465,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Short term investments	0	0
Equity investments trading	0	0
Other investments	74,634,000	54,545,000
Other assets	4,731,000
Other liabilities		(8,359,000)
Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs	79,365,000	46,186,000
Fair Value, Measurements, Recurring | U.S. treasuries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	4,467,345,000	3,331,411,000
Fair Value, Measurements, Recurring | U.S. treasuries | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	4,467,345,000	3,331,411,000
Fair Value, Measurements, Recurring | U.S. treasuries | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | U.S. treasuries | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	343,031,000	174,883,000
Fair Value, Measurements, Recurring | Agencies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Agencies | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	343,031,000	174,883,000
Fair Value, Measurements, Recurring | Agencies | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	6,854,000
Fair Value, Measurements, Recurring | Municipal | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments		0
Fair Value, Measurements, Recurring | Municipal | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments		6,854,000
Fair Value, Measurements, Recurring | Municipal | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments		0
Fair Value, Measurements, Recurring | Non-U.S. government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	497,392,000	279,818,000
Fair Value, Measurements, Recurring | Non-U.S. government | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Non-U.S. government | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	497,392,000	279,818,000
Fair Value, Measurements, Recurring | Non-U.S. government | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Non-U.S. government-backed corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	321,356,000	160,063,000
Fair Value, Measurements, Recurring | Non-U.S. government-backed corporate | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Non-U.S. government-backed corporate | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	321,356,000	160,063,000
Fair Value, Measurements, Recurring | Non-U.S. government-backed corporate | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	3,075,660,000	2,450,244,000
Fair Value, Measurements, Recurring | Corporate | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Corporate | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	3,075,660,000	2,450,244,000
Fair Value, Measurements, Recurring | Corporate | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Agency mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,148,499,000	817,880,000
Fair Value, Measurements, Recurring | Agency mortgage-backed | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Agency mortgage-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,148,499,000	817,880,000
Fair Value, Measurements, Recurring | Agency mortgage-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Non-agency mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	294,604,000	278,680,000
Fair Value, Measurements, Recurring | Non-agency mortgage-backed | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Non-agency mortgage-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	294,604,000	278,680,000
Fair Value, Measurements, Recurring | Non-agency mortgage-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Commercial mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	468,698,000	282,294,000
Fair Value, Measurements, Recurring | Commercial mortgage-backed | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Commercial mortgage-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	468,698,000	282,294,000
Fair Value, Measurements, Recurring | Commercial mortgage-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	555,070,000	306,743,000
Fair Value, Measurements, Recurring | Asset-backed | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Asset-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	555,070,000	306,743,000
Fair Value, Measurements, Recurring | Asset-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0	0
Fair Value, Measurements, Recurring | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	781,641,000	516,571,000
Fair Value, Measurements, Recurring | Catastrophe bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Catastrophe bonds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	781,641,000	516,571,000
Fair Value, Measurements, Recurring | Catastrophe bonds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	271,047,000	242,647,000
Fair Value, Measurements, Recurring | Private equity investments | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Private equity investments | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Private equity investments | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	74,634,000	54,545,000
Fair Value, Measurements, Recurring | Senior secured bank loan funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	22,598,000	14,482,000
Fair Value, Measurements, Recurring | Senior secured bank loan funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Senior secured bank loan funds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Senior secured bank loan funds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	12,091,000	11,233,000
Fair Value, Measurements, Recurring | Hedge funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Hedge funds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Hedge funds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	0
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	4,731,000
Other liabilities		(8,359,000)
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	0	0
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	0	0
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	4,731,000
Other liabilities		(8,359,000)
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts | Significant Unobservable Inputs (Level 3) | Other assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	32,900,000	5,000,000
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts | Significant Unobservable Inputs (Level 3) | Other liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other liabilities	(28,200,000)	(13,300,000)
Fair Value, Measurements, Recurring | Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	16,937,000	12,399,000
Fair Value, Measurements, Recurring | Derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets		484,000
Other liabilities	(1,020,000)
Fair Value, Measurements, Recurring | Derivatives | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	17,957,000	11,915,000
Fair Value, Measurements, Recurring | Derivatives | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	$ 0	$ 0

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity investments	$ 11,171,655,000	$ 8,088,870,000
Other investments	1,087,377,000	784,933,000
Other assets	32,944,000	4,968,000
Other liabilities	(28,213,000)	(13,327,000)
Carrying Value	1,384,105,000	991,127,000
Fair Value	1,468,618,000	974,714,000
Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity investments	11,171,655,000	8,088,870,000
Other investments	1,087,377,000	784,933,000
Other assets	21,668,000	4,040,000
Other investments | Net investment income
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net unrealized gains (losses) included in net investment income	12,200,000	(8,300,000)	$ 24,700,000
Other assets and (liabilities) | Other income (loss)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net unrealized gains (losses) included in net investment income	0	0	$ 0
Municipal | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity investments	0	6,854,000
Private equity investments | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	271,047,000	242,647,000
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity investments	0	0
Other investments	74,634,000	54,545,000
Other assets	4,731,000
Other liabilities		(8,359,000)
Significant Unobservable Inputs (Level 3) | Internal valuation model | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	74,634,000
Significant Unobservable Inputs (Level 3) | Municipal | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity investments		0
Significant Unobservable Inputs (Level 3) | Private equity investments | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	74,634,000	$ 54,545,000
Significant Unobservable Inputs (Level 3) | Private equity investments | External valuation model | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	10,327,000
Significant Unobservable Inputs (Level 3) | Private equity investments | Internal valuation model | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	64,307,000
Significant Unobservable Inputs (Level 3) | Assumed reinsurance contract | Internal valuation model | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	500,000
Other liabilities	(8,767,000)
Significant Unobservable Inputs (Level 3) | Assumed and ceded (re)insurance contracts | Internal valuation model | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	12,997,000
Fair Value Measured at Net Asset Value Per Share
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value	$ 231,102,000
U.S. treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	1.70%
Weighted average credit quality		2.50%
Agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	2.10%
Weighted average credit quality		3.00%
Municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average credit quality		4.80%
Non-U.S. government
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	1.60%
Weighted average credit quality		2.70%
Non-U.S. government-backed corporate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	2.00%
Weighted average credit quality		2.80%
Corporate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	3.00%
Weighted average credit quality		4.90%
Agency mortgage-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	2.50%
Weighted average credit quality		3.50%
Weighted average life	4 years 10 months 24 days	7 years 1 month 6 days
Non-agency prime residential mortgage-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	3.30%
Weighted average credit quality		4.40%
Weighted average life	4 years 9 months 18 days	4 years 8 months 12 days
Alt-A non-agency mortgage-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	3.80%
Weighted average credit quality		4.70%
Weighted average life	6 years 3 months 18 days	6 years 3 months 18 days
Commercial mortgage-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	2.60%
Weighted average credit quality		3.60%
Weighted average life	5 years 8 months 12 days	5 years
Asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	3.30%
Weighted average credit quality		4.30%
Weighted average life	3 years 2 months 12 days	3 years 2 months 12 days
Short term investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Weighted average yield to maturity	1.60%
Weighted average credit quality		2.10%
Private equity investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	$ 271,047,000	$ 242,647,000
Private equity investments | Low
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liquidating period	7 years
Private equity investments | High
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liquidating period	10 years
Private equity investments | Fair Value Measured at Net Asset Value Per Share
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value	$ 196,413,000
Senior secured bank loan funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	22,598,000	14,482,000
Investments fair value	$ 22,600,000
Senior secured bank loan funds | Low
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liquidating period	4 years
Senior secured bank loan funds | High
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liquidating period	5 years
Senior secured bank loan funds | Fair Value Measured at Net Asset Value Per Share
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value	$ 22,598,000
Hedge funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other investments	12,091,000	$ 11,233,000
Hedge funds | Fair Value Measured at Net Asset Value Per Share
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments fair value	$ 12,091,000

Fair Value Measurements (Quanti

Fair Value Measurements (Quantitative Information Used As Level 3 Inputs) (Details) $ in Thousands	Dec. 31, 2019USD ($)$ / shares	Dec. 31, 2018USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	$ 1,087,377	$ 784,933
Other liabilities	(28,213)	(13,327)
Other assets and (liabilities)	32,944	4,968
Fair Value, Measurements, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	1,087,377	784,933
Other assets and (liabilities)	21,668	4,040
Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs	17,283,908	11,774,615
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	74,634	54,545
Other liabilities		(8,359)
Other assets and (liabilities)	4,731
Total other assets and (liabilities) measured at fair value on a recurring basis using Level 3 inputs	79,365	46,186
Fair Value, Measurements, Recurring | Internal valuation model | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	74,634
Fair Value, Measurements, Recurring | Private equity investments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	271,047	242,647
Fair Value, Measurements, Recurring | Private equity investments | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	74,634	54,545
Fair Value, Measurements, Recurring | Private equity investments | External valuation model | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	10,327
Fair Value, Measurements, Recurring | Private equity investments | Internal valuation model | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other investments	64,307
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other liabilities		(8,359)
Other assets and (liabilities)	4,731
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other liabilities		$ (8,359)
Other assets and (liabilities)	4,731
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group one | Internal valuation model | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other assets and (liabilities)	501
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group two | Internal valuation model | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other liabilities	(8,767)
Other assets and (liabilities)	500
Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group three | Internal valuation model | Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other assets and (liabilities)	$ 12,997
Manager pricing | Fair Value, Measurements, Recurring | Private equity investments | External valuation model | Significant Unobservable Inputs (Level 3) | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	103.20
Manager pricing | Fair Value, Measurements, Recurring | Private equity investments | External valuation model | Significant Unobservable Inputs (Level 3) | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	103.77
Manager pricing | Fair Value, Measurements, Recurring | Private equity investments | External valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	103.20
Discount rate | Fair Value, Measurements, Recurring | Private equity investments | Internal valuation model | Significant Unobservable Inputs (Level 3) | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	0.080
Discount rate | Fair Value, Measurements, Recurring | Private equity investments | Internal valuation model | Significant Unobservable Inputs (Level 3) | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	0.100
Discount rate | Fair Value, Measurements, Recurring | Private equity investments | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	0.090
Discount rate | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group two | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs	0.017
Liquidity discount | Fair Value, Measurements, Recurring | Private equity investments | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	0.150
Liquidity discount | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group one | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs	0.013
Bond price | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group one | Internal valuation model | Significant Unobservable Inputs (Level 3) | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	100.29
Bond price | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group one | Internal valuation model | Significant Unobservable Inputs (Level 3) | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	106.26
Bond price | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group one | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs | $ / shares	103.58
Net undiscounted cash flows | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group two | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs	(11,179,000)
Expected loss ratio | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group two | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs	0.331
Expected loss ratio | Fair Value, Measurements, Recurring | Assumed and ceded (re)insurance contracts, group three | Internal valuation model | Significant Unobservable Inputs (Level 3) | Weighted Average or Actual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Significant observable and unobservable inputs	0

Fair Value Measurements (Asse_2

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Other assets and (liabilities)
Total realized and unrealized gains (losses)
Amounts acquired	$ 19,970
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	46,186	$ (2,952)
Total realized and unrealized gains (losses)
Total foreign exchange gains	5
Purchases	13,405	45,254
Settlements	20	983
Amounts acquired	19,970
Ending balance	79,365	46,186
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other income (loss)
Total realized and unrealized gains (losses)
Included in other income	(221)	2,901
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	54,545	0
Total realized and unrealized gains (losses)
Total foreign exchange gains	5
Purchases	17,958	54,545
Settlements	0	0
Amounts acquired	0
Ending balance	74,634	54,545
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other investments | Other income (loss)
Total realized and unrealized gains (losses)
Included in other income	2,126	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other assets and (liabilities)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	(8,359)	(2,952)
Total realized and unrealized gains (losses)
Total foreign exchange gains	0
Purchases	(4,553)	(9,291)
Settlements	20	983
Ending balance	4,731	(8,359)
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other assets and (liabilities) | Other income (loss)
Total realized and unrealized gains (losses)
Included in other income	$ (2,347)	$ 2,901

Fair Value Measurements (Summar

Fair Value Measurements (Summary of the Balances Company Has Elected to Account For at Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Other investments	$ 1,087,377	$ 784,933
Other assets and (liabilities)	32,944	4,968
Other liabilities	$ 28,213	$ 13,327

Fair Value Measurements (Compan

Fair Value Measurements (Company's Portfolio of Other Investments Measured Using Net Asset Valuations) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 359,730
Senior secured bank loan funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	22,600
Fair Value Measured at Net Asset Value Per Share
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	231,102
Fair Value Measured at Net Asset Value Per Share | Private equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	196,413
Unfunded Commitments	351,028
Fair Value Measured at Net Asset Value Per Share | Senior secured bank loan funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	22,598
Unfunded Commitments	8,702
Fair Value Measured at Net Asset Value Per Share | Hedge funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	12,091
Unfunded Commitments	$ 0

Reinsurance (Effect of Reinsura

Reinsurance (Effect of Reinsurance and Retrocessional Activity on Premiums Written and Earned and on Net Claims and Claim Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Premiums written
Direct									$ 461,409	$ 337,587	$ 290,730
Assumed									4,346,341	2,972,840	2,506,810
Ceded									(1,426,257)	(1,178,525)	(926,215)
Net premiums written	$ 725,367	$ 704,130	$ 1,022,965	$ 929,031	$ 411,094	$ 453,255	$ 604,509	$ 663,044	3,381,493	2,131,902	1,871,325
Premiums earned
Direct									404,525	292,219	244,285
Assumed									4,348,261	2,779,796	2,307,219
Ceded									(1,414,383)	(1,095,886)	(833,929)
Net premiums earned (Note 7)	970,125	906,748	911,502	550,028	574,613	531,849	429,385	440,282	3,338,403	1,976,129	1,717,575
Claims and claim expenses
Gross claims and claim expenses incurred									3,221,778	2,578,536	3,420,388
Claims and claim expenses recovered									(1,124,757)	(1,458,518)	(1,558,960)
Net claims and claim expenses incurred	$ 762,093	$ 654,520	$ 453,373	$ 227,035	$ 477,638	$ 410,510	$ 60,167	$ 171,703	$ 2,097,021	$ 1,120,018	$ 1,861,428

Reinsurance (Narrative) (Detail

Reinsurance (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Reinsurance recoverable	$ 2,791,297	$ 2,372,221	$ 1,586,630
Allowance for Reinsurance Recoverable
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation allowance recorded against reinsurance recoverable	$ 7,300	$ 9,000
Reinsurance Recoverable | Largest reinsurance recoverable, Customer One
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	12.70%	15.50%
Reinsurance Recoverable | Largest reinsurance recoverable, Customer Two
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	7.20%	6.70%
Reinsurance Recoverable | Largest reinsurance recoverable, Customer Three
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	7.00%	6.50%
Allowance for Reinsurance Recoverable | Largest reinsurance recoverable, Customer One
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	18.10%	16.20%
Allowance for Reinsurance Recoverable | Largest reinsurance recoverable, Customer Two
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	7.90%	14.80%
Allowance for Reinsurance Recoverable | Largest reinsurance recoverable, Customer Three
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	7.20%	12.30%
Ceded Credit Risk, Secured | Reinsurance Recoverable | Reinsurer Concentration Risk
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	57.50%	60.80%
Rated A- or higher | Ceded Credit Risk, Unsecured | Reinsurance Recoverable | Reinsurer Concentration Risk
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	41.00%	38.00%
Rated lower than A- | Ceded Credit Risk, Unsecured | Reinsurance Recoverable | Reinsurer Concentration Risk
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	1.50%	1.20%

Reserve for Claims and Claim _3

Reserve for Claims and Claim Expenses (Additional Information) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Net reserve for claims and claim expenses	$ 6,593,052,000	$ 3,704,050,000	$ 3,493,778,000	$ 2,568,730,000
Claims and claim expenses recovered	(1,124,757,000)	(1,458,518,000)	(1,558,960,000)
Reinsurance balances payable
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Aggregate deposit liabilities	9,000,000	10,300,000
Aggregate deposit assets
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Aggregate deposit assets	0	0
Deposit Contracts, Underwriting Risk Only
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Claims and claim expenses recovered	0	200,000	200,000
Deposit Contracts, Timing Risk Only
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Increase in other income related to assumed reinsurance contracts	1,300,000	$ 11,200,000	$ 3,700,000
Property
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Net reserve for claims and claim expenses	2,288,762,000
Casualty and Specialty
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Net reserve for claims and claim expenses	$ 4,304,061,000

Reserve for Claims and Claim _4

Reserve for Claims and Claim Expenses (Schedule of Claims and Claim Expense Reserves by Segment) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Case Reserves	$ 2,850,272	$ 1,463,713
Additional Case Reserves	1,760,943	1,425,184
IBNR	4,773,134	3,187,374
Net reserve for claims and claim expenses	9,384,349	6,076,271	$ 5,080,408
Other
Liability for Claims and Claims Adjustment Expense [Line Items]
Case Reserves	440	1,458
Additional Case Reserves	0	0
IBNR	0	3,166
Net reserve for claims and claim expenses	440	4,624
Property | Operating Segments
Liability for Claims and Claims Adjustment Expense [Line Items]
Case Reserves	1,253,406	690,718
Additional Case Reserves	1,631,223	1,308,307
IBNR	1,189,221	1,087,229
Net reserve for claims and claim expenses	4,073,850	3,086,254
Casualty and Specialty | Operating Segments
Liability for Claims and Claims Adjustment Expense [Line Items]
Case Reserves	1,596,426	771,537
Additional Case Reserves	129,720	116,877
IBNR	3,583,913	2,096,979
Net reserve for claims and claim expenses	$ 5,310,059	$ 2,985,393

Reserve for Claims and Claim _5

Reserve for Claims and Claim Expenses (Schedule of Liability for Unpaid Claims and Claims Adjustment Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Net reserves as of beginning of period	$ 3,704,050	$ 3,493,778	$ 2,568,730
Net incurred related to:
Current year	2,123,876	1,390,767	1,902,424
Prior years	(26,855)	(270,749)	(40,996)
Total net incurred	2,097,021	1,120,018	1,861,428
Net paid related to:
Current year	265,649	391,061	450,527
Prior years	832,405	503,708	524,298
Total net paid	1,098,054	894,769	974,825
Amounts acquired	1,858,775	0	0
Foreign exchange	31,260	(14,977)	38,445
Net reserves as of end of period	6,593,052	3,704,050	3,493,778
Reinsurance recoverable as of end of period	2,791,297	2,372,221	1,586,630
Gross reserves as of end of period	$ 9,384,349	$ 6,076,271	$ 5,080,408

Reserve for Claims and Claim _6

Reserve for Claims and Claim Expenses (Schedule of Incurred and Paid Claims Development) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	$ 15,089,621
IBNR and ACR	4,142,784
Cumulative paid claims and claim expenses, net of reinsurance	8,946,583
Outstanding liabilities from accident year 2009 and prior, net of reinsurance	270,317
Claims and claim expenses, net of reinsurance, from the Company's former Bermuda-based insurance operations	229
Adjustment for unallocated claim expenses	51,876
Unamortized fair value adjustments recorded in connection with acquisitions	(69,219)
Liability for claims and claim expenses, net of reinsurance	6,593,052
Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	6,990,689
IBNR and ACR	1,446,950
Cumulative paid claims and claim expenses, net of reinsurance	4,732,479
Outstanding liabilities from accident year 2009 and prior, net of reinsurance	4,283
Adjustment for unallocated claim expenses	19,339
Unamortized fair value adjustments recorded in connection with acquisitions	(10,606)
Liability for claims and claim expenses, net of reinsurance	2,288,762
Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	8,098,932
IBNR and ACR	2,695,834
Cumulative paid claims and claim expenses, net of reinsurance	4,214,104
Outstanding liabilities from accident year 2009 and prior, net of reinsurance	266,034
Adjustment for unallocated claim expenses	32,537
Unamortized fair value adjustments recorded in connection with acquisitions	(58,613)
Liability for claims and claim expenses, net of reinsurance	4,304,061
Accident Year 2010
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,052,931	$ 1,015,540	$ 1,043,565	$ 1,045,490	$ 1,037,725	$ 1,045,727	$ 1,033,341	$ 1,048,747	$ 1,105,041	$ 1,131,892
IBNR and ACR	60,342
Cumulative paid claims and claim expenses, net of reinsurance	928,552	912,776	892,480	859,745	746,454	670,935	603,060	518,162	334,347	146,890
Accident Year 2010 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	731,179	681,435	708,343	706,258	696,844	691,473	657,719	636,962	681,287	720,159
IBNR and ACR	50,422
Cumulative paid claims and claim expenses, net of reinsurance	623,231	612,013	595,131	581,160	481,489	450,624	401,977	345,574	230,552	104,859
Accident Year 2010 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	321,752	334,105	335,222	339,232	340,881	354,254	375,622	411,785	423,754	411,733
IBNR and ACR	9,920
Cumulative paid claims and claim expenses, net of reinsurance	305,321	300,763	297,349	278,585	264,965	220,311	201,083	172,588	103,795	$ 42,031
Accident Year 2011
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,664,869	1,678,015	1,683,614	1,698,378	1,738,452	1,768,793	1,827,258	1,926,506	1,989,024
IBNR and ACR	55,191
Cumulative paid claims and claim expenses, net of reinsurance	1,565,359	1,550,195	1,530,030	1,493,174	1,449,060	1,330,492	1,143,829	728,464	311,906
Accident Year 2011 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,302,141	1,321,137	1,333,982	1,338,187	1,369,567	1,393,110	1,422,659	1,491,770	1,559,069
IBNR and ACR	24,335
Cumulative paid claims and claim expenses, net of reinsurance	1,264,414	1,257,516	1,252,204	1,230,503	1,207,136	1,121,374	965,668	590,346	262,987
Accident Year 2011 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	362,728	356,878	349,632	360,191	368,885	375,683	404,599	434,736	429,955
IBNR and ACR	30,856
Cumulative paid claims and claim expenses, net of reinsurance	300,945	292,679	277,826	262,671	241,924	209,118	178,161	138,118	$ 48,919
Accident Year 2012
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	907,212	901,049	894,168	891,981	927,438	958,139	1,021,668	1,138,018
IBNR and ACR	48,297
Cumulative paid claims and claim expenses, net of reinsurance	783,106	752,614	721,942	647,618	596,634	522,264	416,808	267,764
Accident Year 2012 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	331,865	336,719	344,535	356,310	375,098	395,203	429,425	559,946
IBNR and ACR	12,351
Cumulative paid claims and claim expenses, net of reinsurance	313,976	308,822	305,627	291,027	280,195	253,699	205,567	165,850
Accident Year 2012 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	575,347	564,330	549,633	535,671	552,340	562,936	592,243	578,072
IBNR and ACR	35,946
Cumulative paid claims and claim expenses, net of reinsurance	469,130	443,792	416,315	356,591	316,439	268,565	211,241	$ 101,914
Accident Year 2013
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	699,767	718,563	737,158	761,033	810,934	861,093	912,545
IBNR and ACR	43,792
Cumulative paid claims and claim expenses, net of reinsurance	615,463	587,978	554,686	496,380	434,508	340,652	131,829
Accident Year 2013 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	222,939	224,748	228,622	240,945	265,570	287,694	317,258
IBNR and ACR	1,092
Cumulative paid claims and claim expenses, net of reinsurance	219,231	216,176	213,351	206,376	191,181	155,459	80,083
Accident Year 2013 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	476,828	493,815	508,536	520,088	545,364	573,399	595,287
IBNR and ACR	42,700
Cumulative paid claims and claim expenses, net of reinsurance	396,232	371,802	341,335	290,004	243,327	185,193	$ 51,746
Accident Year 2014
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	953,904	948,264	966,802	990,050	997,906	1,024,813
IBNR and ACR	114,985
Cumulative paid claims and claim expenses, net of reinsurance	741,844	691,774	630,417	554,398	432,761	230,826
Accident Year 2014 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	265,229	264,754	265,820	270,618	283,608	306,731
IBNR and ACR	4,554
Cumulative paid claims and claim expenses, net of reinsurance	247,663	241,139	234,144	222,509	184,140	106,618
Accident Year 2014 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	688,675	683,510	700,982	719,432	714,298	718,082
IBNR and ACR	110,431
Cumulative paid claims and claim expenses, net of reinsurance	494,181	450,635	396,273	331,889	248,621	$ 124,208
Accident Year 2015
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,133,632	1,145,983	1,175,927	1,156,856	1,171,023
IBNR and ACR	131,005
Cumulative paid claims and claim expenses, net of reinsurance	879,950	781,622	662,001	495,119	262,085
Accident Year 2015 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	301,733	307,088	317,865	334,572	368,766
IBNR and ACR	11,672
Cumulative paid claims and claim expenses, net of reinsurance	279,165	268,545	249,182	215,134	126,831
Accident Year 2015 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	831,899	838,895	858,062	822,284	802,257
IBNR and ACR	119,333
Cumulative paid claims and claim expenses, net of reinsurance	600,785	513,077	412,819	279,985	$ 135,254
Accident Year 2016
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,426,575	1,432,001	1,458,767	1,401,451
IBNR and ACR	251,952
Cumulative paid claims and claim expenses, net of reinsurance	971,424	826,502	623,440	286,317
Accident Year 2016 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	432,269	443,135	458,525	445,532
IBNR and ACR	53,990
Cumulative paid claims and claim expenses, net of reinsurance	350,646	324,296	258,355	119,908
Accident Year 2016 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	994,306	988,866	1,000,242	955,919
IBNR and ACR	197,962
Cumulative paid claims and claim expenses, net of reinsurance	620,778	502,206	365,085	$ 166,409
Accident Year 2017
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	2,632,396	2,724,795	2,940,713
IBNR and ACR	731,975
Cumulative paid claims and claim expenses, net of reinsurance	1,371,477	1,067,481	745,098
Accident Year 2017 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,348,260	1,446,566	1,640,129
IBNR and ACR	295,210
Cumulative paid claims and claim expenses, net of reinsurance	824,443	660,491	534,097
Accident Year 2017 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,284,136	1,278,229	1,300,584
IBNR and ACR	436,765
Cumulative paid claims and claim expenses, net of reinsurance	547,034	406,990	$ 211,001
Accident Year 2018
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	2,338,291	2,198,980
IBNR and ACR	940,346
Cumulative paid claims and claim expenses, net of reinsurance	804,566	587,619
Accident Year 2018 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,054,884	945,829
IBNR and ACR	273,477
Cumulative paid claims and claim expenses, net of reinsurance	450,125	432,201
Accident Year 2018 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,283,407	1,253,151
IBNR and ACR	666,869
Cumulative paid claims and claim expenses, net of reinsurance	354,441	$ 155,418
Accident Year 2019
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	2,280,044
IBNR and ACR	1,764,899
Cumulative paid claims and claim expenses, net of reinsurance	284,842
Accident Year 2019 | Property
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,000,190
IBNR and ACR	719,847
Cumulative paid claims and claim expenses, net of reinsurance	159,585
Accident Year 2019 | Casualty and Specialty
Claims Development [Line Items]
Incurred claims and claim expenses, net of reinsurance	1,279,854
IBNR and ACR	1,045,052
Cumulative paid claims and claim expenses, net of reinsurance	125,257
RenaissanceRe UK
Claims Development [Line Items]
Liability for claims and claim expenses, net of reinsurance	196,811
RenaissanceRe UK | Property
Claims Development [Line Items]
Liability for claims and claim expenses, net of reinsurance	17,536
RenaissanceRe UK | Casualty and Specialty
Claims Development [Line Items]
Liability for claims and claim expenses, net of reinsurance	$ 179,275

Reserve for Claims and Claim _7

Reserve for Claims and Claim Expenses (Prior Year Development of the Reserve for Net Claims and Claim Expenses) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	$ (26,855)	$ (270,749)	$ (40,996)
Other
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(40)	(197)	(1,583)
Property
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(2,933)	(221,290)	(45,596)
Property | Actuarial assumption changes
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	9,245	(5,682)	842
Property | Large and small catastrophe events and attritional loss movements
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(12,178)	(215,608)	(46,438)
Property | Large catastrophe events
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(17,557)	(182,029)	(7,640)
Property | 2017 Large Loss Events
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(101,572)	(172,512)
Property | New Zealand Earthquake (2011)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(7,497)		5,807
Property | Tohoku Earthquake and Tsunami (2011)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(5,198)
Property | Storm Sandy (2012)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years			(4,395)
Property | April and May U.S. Tornadoes (2011)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years			(4,177)
Property | New Zealand Earthquake (2010)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	47,071		4,061
Property | 2018 Large Loss Events
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	81,555
Property | Other
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(31,916)	(9,517)	(8,936)
Property | Small catastrophe events and attritional loss movements
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	5,379	(33,579)	(38,798)
Property | Tianjin Explosion (2015)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years			(8,002)
Property | Fort McMurray Wildfire (2016)
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years			(6,364)
Property | Other small catastrophe events and attritional loss movements
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	5,379	(33,579)	(24,432)
Casualty and Specialty
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(23,882)	(49,262)	6,183
Casualty and Specialty | Actuarial methods - actual reported claims less than expected claims
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	(52,796)	(41,476)	(24,836)
Casualty and Specialty | Ogden Rate change
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	0	0	33,481
Casualty and Specialty | Actuarial assumption changes
Liability for Catastrophe Claims [Line Items]
Net claims and claim expenses incurred – prior accident years	$ 28,914	$ (7,786)	$ (2,462)
High | Discount rate | Ogden Rate
Liability for Catastrophe Claims [Line Items]
Cash surrender value, measurement input			0.025
Low | Discount rate | Ogden Rate
Liability for Catastrophe Claims [Line Items]
Cash surrender value, measurement input			(0.0075)

Reserve for Claims and Claim _8

Reserve for Claims and Claim Expenses (Reconciliation of the Disclosure of Incurred and Paid Claims Development to the Reserve for Claims and Claim Expenses) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Net reserve for claims and claim expenses	$ 6,593,052	$ 3,704,050	$ 3,493,778	$ 2,568,730
Reinsurance recoverable	2,791,297
Total gross reserve for claims and claim expenses	9,384,349	6,076,271	$ 5,080,408
Other
Liability for Claims and Claims Adjustment Expense [Line Items]
Net reserve for claims and claim expenses	229
Reinsurance recoverable	211
Total gross reserve for claims and claim expenses	440	$ 4,624
Property
Liability for Claims and Claims Adjustment Expense [Line Items]
Net reserve for claims and claim expenses	2,288,762
Reinsurance recoverable	1,785,088
Casualty and Specialty
Liability for Claims and Claims Adjustment Expense [Line Items]
Net reserve for claims and claim expenses	4,304,061
Reinsurance recoverable	$ 1,005,998

Reserve for Claims and Claim _9

Reserve for Claims and Claim Expenses (Historical Claims Duration) (Details)	Dec. 31, 2019
Property
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Average annual percentage payout, year one	29.90%
Average annual percentage payout, year two	17.00%
Average annual percentage payout, year three	17.80%
Average annual percentage payout, year four	8.70%
Average annual percentage payout, year five	5.40%
Average annual percentage payout, year six	2.70%
Average annual percentage payout, year seven	4.90%
Average annual percentage payout, year eight	1.00%
Average annual percentage payout, year nine	1.20%
Average annual percentage payout, year ten	1.50%
Casualty and Specialty
Short-duration Insurance Contracts, Historical Claims Duration [Line Items]
Average annual percentage payout, year one	14.30%
Average annual percentage payout, year two	18.40%
Average annual percentage payout, year three	13.00%
Average annual percentage payout, year four	10.30%
Average annual percentage payout, year five	8.80%
Average annual percentage payout, year six	8.20%
Average annual percentage payout, year seven	4.60%
Average annual percentage payout, year eight	4.70%
Average annual percentage payout, year nine	1.70%
Average annual percentage payout, year ten	1.40%

Reserve for Claims and Claim_10

Reserve for Claims and Claim Expenses (Cumulative Number of Claims Reported) (Details) - Excess of Loss Reinsurance Contracts	Dec. 31, 2019claim
Accident Year 2010 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	835
Accident Year 2010 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	1,215
Accident Year 2011 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	1,388
Accident Year 2011 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	1,964
Accident Year 2012 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	922
Accident Year 2012 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	2,263
Accident Year 2013 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	799
Accident Year 2013 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	2,712
Accident Year 2014 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	744
Accident Year 2014 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	3,421
Accident Year 2015 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	758
Accident Year 2015 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	3,783
Accident Year 2016 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	1,089
Accident Year 2016 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	4,135
Accident Year 2017 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	2,215
Accident Year 2017 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	3,294
Accident Year 2018 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	2,050
Accident Year 2018 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	2,148
Accident Year 2019 | Property
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	861
Accident Year 2019 | Casualty and Specialty
Claims Development [Line Items]
Cumulative number of reported claims (in claims)	816

Debt and Credit Facilities (Sch

Debt and Credit Facilities (Schedule of Carrying Values and Estimated Fair Values of Debt Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Apr. 02, 2019	Dec. 31, 2018	Jun. 29, 2017	May 04, 2015	Mar. 24, 2015
Debt Instrument [Line Items]
Fair Value	$ 1,468,618		$ 974,714
Carrying Value	$ 1,384,105		991,127
RenaissanceRe Finance, Inc. | 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Interest rate						3.70%
DaVinciRe Holdings Ltd. | 4.750% Senior Notes due 2025 (DaVinciRe)
Debt Instrument [Line Items]
Interest rate					4.75%
Senior Notes | 3.600% Senior Notes due 2029
Debt Instrument [Line Items]
Interest rate	3.60%	3.60%
Senior Notes | 3.450% Senior Notes due 2027
Debt Instrument [Line Items]
Interest rate	3.45%
Senior Notes | 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Interest rate	3.70%
Senior Notes | 5.750% Senior Notes due 2020
Debt Instrument [Line Items]
Interest rate	5.75%
Senior Notes | 4.750% Senior Notes due 2025 (DaVinciRe)
Debt Instrument [Line Items]
Interest rate	4.75%
Senior Notes | RenaissanceRe Finance, Inc. | 3.600% Senior Notes due 2029
Debt Instrument [Line Items]
Fair Value	$ 424,920		0
Carrying Value	391,475		0
Senior Notes | RenaissanceRe Finance, Inc. | 3.450% Senior Notes due 2027
Debt Instrument [Line Items]
Interest rate				3.45%
Fair Value	314,070		283,680
Carrying Value	296,292		295,797
Senior Notes | RenaissanceRe Finance, Inc. | 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Fair Value	318,567		292,557
Carrying Value	298,057		297,688
Senior Notes | RenaissanceRe Finance, Inc. | 5.750% Senior Notes due 2020
Debt Instrument [Line Items]
Fair Value	251,030		255,938
Carrying Value	249,931		249,602
Senior Notes | DaVinciRe Holdings Ltd. | 4.750% Senior Notes due 2025 (DaVinciRe)
Debt Instrument [Line Items]
Fair Value	160,031		142,539
Carrying Value	$ 148,350		$ 148,040

Debt and Credit Facilities (Deb

Debt and Credit Facilities (Debt Obligations Narrative) (Details) - USD ($)	Apr. 02, 2019	Dec. 31, 2019	Jun. 29, 2017	May 04, 2015	Mar. 24, 2015	Mar. 17, 2010	Nov. 02, 2005
Bridge Loan | Platinum Underwriters Holdings, Ltd.
Debt Instrument [Line Items]
Short-term debt					$ 300,000,000
Senior Notes | 3.600% Senior Notes due 2029
Debt Instrument [Line Items]
Interest rate	3.60%	3.60%
Face amount	$ 400,000,000
Repayments of long-term lines of credit	$ 200,000,000
Senior Notes | 3.450% Senior Notes due 2027
Debt Instrument [Line Items]
Interest rate		3.45%
Senior Notes | 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Interest rate		3.70%
Senior Notes | 5.75% Senior Notes Due March 15, 2020
Debt Instrument [Line Items]
Interest rate		5.75%
Senior Notes | 4.750% Senior Notes Due May 1, 2025
Debt Instrument [Line Items]
Interest rate		4.75%
RenaissanceRe Finance, Inc. | 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Interest rate					3.70%
Face amount					$ 300,000,000
RenaissanceRe Finance, Inc. | Senior Notes | 3.450% Senior Notes due 2027
Debt Instrument [Line Items]
Interest rate			3.45%
Face amount			$ 300,000,000
RenRe North America Holdings Inc | 5.75% Senior Notes Due March 15, 2020
Debt Instrument [Line Items]
Interest rate						5.75%
Face amount						$ 250,000,000
Platinum Underwriters Finance, Inc | Senior Notes | Series B 7.50% Notes Due June 1, 2017
Debt Instrument [Line Items]
Interest rate							7.50%
Face amount							$ 250,000,000
DaVinciRe Holdings Ltd.
Debt Instrument [Line Items]
Loan agreement with related party				$ 100,000,000
DaVinciRe Holdings Ltd. | 4.750% Senior Notes Due May 1, 2025
Debt Instrument [Line Items]
Interest rate				4.75%
Face amount				$ 150,000,000

Debt and Credit Facilities (S_2

Debt and Credit Facilities (Schedule of Maturities of Long-term Debt) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Debt Disclosure [Abstract]
2020	$ 250,000
2021	0
2022	0
2023	0
2024	0
After 2024	1,150,000
Unamortized discount and debt issuance expenses	(15,895)
Total	$ 1,384,105

Debt and Credit Facilities (S_3

Debt and Credit Facilities (Schedule of Credit Facilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Line of Credit Facility [Line Items]
Credit facilities outstanding		$ 1,110,756
Revolving Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding	$ 0	0
Letter of Credit | Secured Bilateral Facility | Line of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		298,063
Letter of Credit | Unsecured Bilateral Facility | Line of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		381,770
Letter of Credit | Bank of Montreal, Citibank Europe and ING Bank | Line of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		290,000
TMR | Letter of Credit | Line of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		$ 140,923

Debt and Credit Facilities (Cre

Debt and Credit Facilities (Credit Facilities Narrative) (Details)	Nov. 23, 2015USD ($)	Dec. 31, 2019USD ($)	Nov. 07, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 21, 2019USD ($)	Mar. 22, 2019USD ($)	Nov. 09, 2018USD ($)	May 31, 2016USD ($)	Sep. 17, 2010USD ($)
Line of Credit Facility [Line Items]
Credit facilities outstanding				$ 1,110,756,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Letter of credit aggregate commitment							$ 500,000,000
Line of credit facility, maximum borrowing capacity							750,000,000
Debt to capital ratio		0.35
Minimum net worth requirements		$ 2,900,000,000
Unsecured Bilateral Facility | Wells Fargo | Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity					$ 25,000,000
Credit facilities outstanding		0
Unsecured Bilateral Facility | Citibank Europe PLC | Letter of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		270,700,000
Unsecured Bilateral Facility | Credit Suisse (Switzerland) Ltd. | Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity						$ 125,000,000
Debt to capital ratio						0.35
Minimum net worth requirements						$ 3,000,000,000
Credit facilities outstanding		111,100,000
Secured Bilateral Facility | Wells Fargo | Letter of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		31,500,000
Secured Bilateral Facility | Citibank Europe PLC | Letter of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		266,500,000
Renaissance Reinsurance FAL Facility | Letter of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding		290,000,000
Bridge Loan | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity							$ 50,000,000
Line of Credit | Bank of Montreal, Citibank Europe and ING Bank | Letter of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding				290,000,000
Line of Credit | Unsecured Bilateral Facility | Letter of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding				381,770,000
Line of Credit | Secured Bilateral Facility | Letter of Credit
Line of Credit Facility [Line Items]
Credit facilities outstanding				$ 298,063,000
Bilateral Facility Participants | Letter of Credit | Secured Bilateral Facility | Citibank Europe PLC
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity									$ 300,000,000
Loan agreement, remaining borrowing capacity		$ 33,500,000
Renaissance Reinsurance U.S. Inc. | Letter of Credit | Secured Bilateral Facility | Citibank Europe PLC
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity									$ 25,000,000
Syndicate 1458 | Letter of Credit | Renaissance Reinsurance FAL Facility | Bank of Montreal, Citibank Europe and ING Bank
Line of Credit Facility [Line Items]
Collateral amount, percent of aggregate outstanding letters of credit in case of Full Collateralization Event		100.00%
Syndicate 1458 | Line of Credit | Renaissance Reinsurance FAL Facility | Bank of Montreal, Citibank Europe and ING Bank
Line of Credit Facility [Line Items]
Aggregate amount of issuances	$ 140,000,000
Termination period from date of notice	4 years
Syndicate 1458 | Line of Credit | Renaissance Reinsurance FAL Facility | Bank of Montreal, Citibank Europe and ING Bank | Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			$ 290,000,000					$ 255,000,000
Greater than or equal to | Syndicate 1458 | Letter of Credit | Renaissance Reinsurance FAL Facility | Bank of Montreal, Citibank Europe and ING Bank
Line of Credit Facility [Line Items]
Collateral amount, percent of aggregate outstanding letters of credit	60.00%
Less than | Syndicate 1458 | Letter of Credit | Renaissance Reinsurance FAL Facility | Bank of Montreal, Citibank Europe and ING Bank
Line of Credit Facility [Line Items]
Collateral amount, percent of aggregate outstanding letters of credit	100.00%
Letter of Credit | Top Layer Reinsurance Ltd.
Line of Credit Facility [Line Items]
Collateralized letter of credit and reimbursement agreement		$ 37,500,000
Capital Support Agreement | Letter of Credit | Top Layer Reinsurance Ltd.
Line of Credit Facility [Line Items]
Mandatory capital contribution in the event of capital and surplus reduction below a specified level		$ 50,000,000

Noncontrolling Interests (Summa

Noncontrolling Interests (Summary of Redeemable Noncontrolling Interest) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests	$ 3,071,308	$ 2,051,700
Net income attributable to redeemable noncontrolling interests	201,469	41,553	$ (132,282)
DaVinciRe Holdings Ltd.
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests	1,435,581	1,034,946	1,011,659
Net income attributable to redeemable noncontrolling interests	127,084	27,638	(134,860)
RenaissanceRe Medici Fund Ltd.
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests	632,112	416,765	284,847
Net income attributable to redeemable noncontrolling interests	25,759	13,926	2,578
Vermeer Reinsurance Ltd.
Redeemable Noncontrolling Interest [Line Items]
Redeemable noncontrolling interests	1,003,615	599,989	0
Net income attributable to redeemable noncontrolling interests	$ 48,626	$ (11)	$ 0

Noncontrolling Interests (Narra

Noncontrolling Interests (Narrative) (Details) - USD ($) $ in Thousands	Jun. 01, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
DaVinci Reinsurance Ltd.
Noncontrolling Interest [Line Items]
Redeemable noncontrolling interest, ownership percentage	21.90%	22.10%	21.90%	22.10%
Noncontrolling interest, increase from sale of parent equity interest	$ 11,600
RenaissanceRe Medici Fund Ltd.
Noncontrolling Interest [Line Items]
Redeemable noncontrolling interest, ownership percentage		16.60%	12.10%	16.60%
DaVinciRe Holdings Ltd.
Noncontrolling Interest [Line Items]
Noncontrolling interest, value subscribed	349,200		$ 274,699	$ 0
Redemption of shares from redeemable noncontrolling interests			$ 1,148	4,351
DaVinciRe Holdings Ltd. | High
Noncontrolling Interest [Line Items]
Share repurchase requests, limit			25.00%
DaVinciRe Holdings Ltd. | Redeemable Noncontrolling Interest
Noncontrolling Interest [Line Items]
Share repurchase requests, percent of aggregate shares, limit			50.00%
RenaissanceRe Medici Fund Ltd.
Noncontrolling Interest [Line Items]
Noncontrolling interest, value subscribed			$ 236,989	208,482
Written notice period for redemption			30 days
Redemption of shares from redeemable noncontrolling interests			$ 47,401	90,490
Vermeer Reinsurance Ltd.
Noncontrolling Interest [Line Items]
Noncontrolling interest, value subscribed			$ 355,000	$ 600,000
Participating, Non-voting Common Shares | Vermeer Reinsurance Ltd.
Noncontrolling Interest [Line Items]
Noncontrolling interest, value subscribed		$ 600,000
Voting, Non-participating Shares | Vermeer Reinsurance Ltd.
Noncontrolling Interest [Line Items]
Noncontrolling interest, value subscribed		$ 1
Third-Party Investors | DaVinciRe Holdings Ltd.
Noncontrolling Interest [Line Items]
Noncontrolling interest, value subscribed	263,100
RenaissanceRe Holdings Ltd. | DaVinciRe Holdings Ltd.
Noncontrolling Interest [Line Items]
Noncontrolling interest, value subscribed	$ 86,100

Noncontrolling Interests (Sched

Noncontrolling Interests (Schedule of Redeemable Noncontrolling Interest Activity) (Details) - USD ($) $ in Thousands	Jun. 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Activity in redeemable noncontrolling interest
Beginning balance		$ 2,051,700
Comprehensive income:
Net income attributable to redeemable noncontrolling interests		201,469	$ 41,553	$ (132,282)
Ending balance		3,071,308	2,051,700
DaVinciRe Holdings Ltd.
Activity in redeemable noncontrolling interest
Beginning balance		1,034,946	1,011,659
Redemption of shares from redeemable noncontrolling interests, net of adjustments		(1,148)	(4,351)
Sale of shares to redeemable noncontrolling interests	$ 349,200	274,699	0
Comprehensive income:
Net income attributable to redeemable noncontrolling interests		127,084	27,638	(134,860)
Ending balance		1,435,581	1,034,946	1,011,659
RenaissanceRe Medici Fund Ltd.
Activity in redeemable noncontrolling interest
Beginning balance		416,765	284,847
Redemption of shares from redeemable noncontrolling interests, net of adjustments		(47,401)	(90,490)
Sale of shares to redeemable noncontrolling interests		236,989	208,482
Comprehensive income:
Net income attributable to redeemable noncontrolling interests		25,759	13,926	2,578
Ending balance		632,112	416,765	284,847
Vermeer Reinsurance Ltd.
Activity in redeemable noncontrolling interest
Beginning balance		599,989	0
Sale of shares to redeemable noncontrolling interests		355,000	600,000
Comprehensive income:
Net income attributable to redeemable noncontrolling interests		48,626	(11)	0
Ending balance		$ 1,003,615	$ 599,989	$ 0

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Variable Interest Entity [Line Items]
Total assets	$ 26,330,094,000		$ 18,676,196,000
Total liabilities	17,287,419,000		11,579,416,000
Redeemable noncontrolling interests	3,071,308,000		2,051,700,000
Ceded premiums written	1,426,257,000		1,178,525,000	$ 926,215,000
Ceded premiums earned	1,414,383,000		1,095,886,000	833,929,000
Reinsurance recoverable	2,791,297,000
Investments in other ventures, under equity method (Note 5)	106,549,000		115,172,000
Upsilon RFO Re Ltd. | Primary Beneficiary
Variable Interest Entity [Line Items]
Total assets	3,100,000,000		2,200,000,000
Total liabilities	3,100,000,000		2,200,000,000
Upsilon RFO Re Ltd. | Primary Beneficiary | Investor
Variable Interest Entity [Line Items]
Payments of capital distributions	279,200,000
Upsilon RFO Re Ltd. | Primary Beneficiary | Investor | Non-voting preference shares
Variable Interest Entity [Line Items]
Investment in variable interest entity	$ 618,700,000	$ 512,800,000	856,700,000
Upsilon RFO Re Ltd. | Primary Beneficiary | RenaissanceRe Holdings Ltd.
Variable Interest Entity [Line Items]
Payments of capital distributions			$ 31,000,000
Variable interest entity, ownership percentage	16.50%		14.00%
Upsilon RFO Re Ltd. | Primary Beneficiary | RenaissanceRe Holdings Ltd. | Non-voting preference shares
Variable Interest Entity [Line Items]
Investment in variable interest entity	$ 100,000,000		$ 109,800,000
Vermeer Reinsurance Ltd.
Variable Interest Entity [Line Items]
Redeemable noncontrolling interests	1,003,615,000		599,989,000	0
Vermeer Reinsurance Ltd. | Primary Beneficiary
Variable Interest Entity [Line Items]
Total assets	1,000,000,000		600,400,000
Total liabilities	23,200,000		400,000
Redeemable noncontrolling interests	1,000,000,000		600,000,000
Mona Lisa Re | Not Primary Beneficiary
Variable Interest Entity [Line Items]
Total assets	6,000		41,000
Total liabilities	6,000		41,000
Mona Lisa Re | Not Primary Beneficiary | Renaissance Reinsurance Ltd.
Variable Interest Entity [Line Items]
Ceded premiums written	0		200,000	400,000
Ceded premiums earned	0		200,000	4,100,000
Mona Lisa Re | Not Primary Beneficiary | DaVinci Reinsurance Ltd.
Variable Interest Entity [Line Items]
Ceded premiums written	0
Ceded premiums earned	0		200,000	$ 2,900,000
Fibonacci Reinsurance Ltd. | Not Primary Beneficiary | Other investments
Variable Interest Entity [Line Items]
Fair value of investment	400,000		6,000,000
Renaissance Reinsurance Ltd. | Not Primary Beneficiary | Fibonacci Reinsurance Ltd.
Variable Interest Entity [Line Items]
Ceded premiums written	100,000		9,100,000
Ceded premiums earned	100,000		10,000,000
Ceded net claims and claim expenses	7,500,000		0
Reinsurance recoverable	7,500,000		0
Langhorne Holdings LLC | Not Primary Beneficiary
Variable Interest Entity [Line Items]
Investments in other ventures, under equity method (Note 5)	1,700,000		1,300,000
Langhorne Partners | Not Primary Beneficiary
Variable Interest Entity [Line Items]
Investments in other ventures, under equity method (Note 5)	$ 100,000		$ 100,000

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Details)	Dec. 31, 2019USD ($)directorperiod$ / sharesshares	Dec. 13, 2019$ / shares	Sep. 30, 2019$ / shares	Sep. 13, 2019$ / shares	Jun. 28, 2019$ / shares	Jun. 14, 2019$ / shares	Mar. 29, 2019$ / shares	Mar. 22, 2019shares	Mar. 15, 2019$ / shares	Dec. 20, 2018shares	Oct. 30, 2018USD ($)	Jun. 27, 2013USD ($)shares	Jun. 30, 2018USD ($)$ / sharesshares	May 31, 2013USD ($)$ / sharesshares	Mar. 31, 2004USD ($)$ / sharesshares	Dec. 31, 2019USD ($)directorperiod$ / sharesshares	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)$ / sharesshares	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)$ / sharesshares	Mar. 31, 2018USD ($)	Dec. 31, 2019USD ($)directorperiod$ / sharesshares	Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)shares	Nov. 10, 2017USD ($)
Class of Stock [Line Items]
Aggregate authorized shares (in shares) | shares	325,000,000															325,000,000								325,000,000
Authorized common shares (in shares) | shares	225,000,000															225,000,000								225,000,000
Authorized preference shares (in shares) | shares	100,000,000															100,000,000								100,000,000
Dividends on preference shares | $																$ 9,189,000	$ 9,189,000	$ 9,189,000	$ 9,189,000	$ 9,189,000	$ 9,708,000	$ 5,596,000	$ 5,595,000	$ 36,756,000	$ 30,088,000	$ 22,381,000
Dividends on common shares | $																								(59,400,000)	(52,800,000)	(51,400,000)
Preference shares, issued, value | $																								$ 0	$ 241,448,000	$ 0
Par value (in usd per share)	$ 1															$ 1				$ 1				$ 1	$ 1
Preference shares, shares outstanding (in shares) | shares	16,010,000															16,010,000				16,010,000				16,010,000	16,010,000
Shares issued (in shares) | shares	16,010,000															16,010,000				16,010,000				16,010,000	16,010,000
Common shares
Class of Stock [Line Items]
Preference shares, shares issued (in shares) | shares																								1,739,000	1,947,000	0
Common shares | Private Placement | State Farm
Class of Stock [Line Items]
Investment Agreement, shares issued in transaction (in shares) | shares										1,947,496
Investment Agreement, consideration received per transaction | $											$ 250,000,000
Common shares
Class of Stock [Line Items]
Dividends declared per common share (in usd per share)		$ 0.34		$ 0.34		$ 0.34			$ 0.34
Dividends paid per common share (in usd per share)	$ 0.34		$ 0.34		$ 0.34		$ 0.34
Share repurchase program, authorized aggregate amount | $																											$ 500,000,000
Share repurchase program, remaining authorized shares (in shares) | $	$ 500,000,000															$ 500,000,000								$ 500,000,000
Series C Preferred Stock
Class of Stock [Line Items]
Dividend rate, percentage																								6.08%
Liquidation preference per annum (in usd per share)	$ 1.52															$ 1.52								$ 1.52
Quarterly liquidation preference (in usd per share)	$ 0.38															$ 0.38								$ 0.38
Preference shares, issued, value | $															$ 250,000,000
Preference shares, shares issued (in shares) | shares															10,000,000
Par value (in usd per share)															$ 25
Preference shares, shares redeemed (in shares) | shares												5,000,000
Preference shares, redemption amount | $												$ 125,000,000
Preference shares, shares outstanding (in shares) | shares												5,000,000
Proceeds from issuance of convertible preferred stock | $													$ 250,000,000
Right to elect directors, required number of dividend periods in arrears | period	6															6								6
Right to elect directors, number of directors | director	2															2								2
Series E Preferred Stock
Class of Stock [Line Items]
Dividend rate, percentage																								5.375%
Liquidation preference per annum (in usd per share)	$ 1.34375															$ 1.34375								$ 1.34375
Quarterly liquidation preference (in usd per share)	0.3359375															0.3359375								0.3359375
Preference shares, issued, value | $														$ 275,000,000
Preference shares, shares issued (in shares) | shares														11,000,000
Par value (in usd per share)														$ 25
Redemption price per share (in usd per share)	25															25								$ 25
Series F Preferred Stock
Class of Stock [Line Items]
Dividend rate, percentage																								5.75%
Liquidation preference per annum (in usd per share)	1,437.50															1,437.50								$ 1,437.50
Quarterly liquidation preference (in usd per share)	359.375															359.375								359.375
Shares issued (in shares) | shares													10,000									10,000
Liquidation preference (in usd per share)													$ 25,000									$ 25,000
Redemption price per share (in usd per share)													$ 25,000									$ 25,000
Depositary Shares
Class of Stock [Line Items]
Liquidation preference per annum (in usd per share)	1.4375															1.4375								1.4375
Quarterly liquidation preference (in usd per share)	$ 0.359375															$ 0.359375								$ 0.359375
Shares issued (in shares) | shares													10,000,000									10,000,000
Percentage interest in underlying shares													0.10%									0.10%
Redemption price per share (in usd per share)													$ 25									$ 25
TMR
Class of Stock [Line Items]
Shares issued (in shares) | shares								1,739,071

Shareholders' Equity (Rollforwa

Shareholders' Equity (Rollforward of Shares Issued and Outstanding) (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued - January 1 (in shares)	42,207,390
Shares outstanding - January 1 (in shares)	42,207,390
Shares issued - December 31 (in shares)	44,148,116	42,207,390
Shares outstanding - December 31 (in shares)	44,148,116	42,207,390
Common shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued - January 1 (in shares)	42,207,000	40,024,000	41,187,000
Shares outstanding - January 1 (in shares)	42,207,000	40,024,000	41,187,000
Issuance of shares (in shares)	1,739,000	1,947,000	0
Repurchase of shares (in shares)	0	0	(1,322,000)
Exercise of options and issuance of restricted stock awards (in shares)	202,000	236,000	159,000
Shares issued - December 31 (in shares)	44,148,000	42,207,000	40,024,000
Shares outstanding - December 31 (in shares)	44,148,000	42,207,000	40,024,000

Earnings Per Share (Computation

Earnings Per Share (Computation of Basic and Diluted Earnings Per Common Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net income (loss) available (attributable) to RenaissanceRe common shareholders	$ 33,773	$ 36,698	$ 367,854	$ 273,717	$ (83,906)	$ 32,681	$ 191,788	$ 56,713	$ 712,042	$ 197,276	$ (244,770)
Amount allocated to participating common shareholders									(8,545)	(2,121)	(457)
Net income (loss) allocated to RenaissanceRe common shareholders									$ 703,497	$ 195,155	$ (245,227)
Denominator:
Denominator for basic income (loss) per RenaissanceRe common share - weighted average common shares (in shares)	43,467	43,462	43,483	42,065	40,111	39,624	39,641	39,552	43,119	39,732	39,854
Per common share equivalents of employee stock options and performance shares (in shares)									56	23	0
Denominator for diluted income (loss) per RenaissanceRe common share - adjusted weighted average common shares and assumed conversions (in shares)	43,552	43,537	43,521	42,091	40,111	39,637	39,654	39,599	43,175	39,755	39,854
Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – basic (in usd per share)	$ 0.77	$ 0.83	$ 8.36	$ 6.43	$ (2.10)	$ 0.82	$ 4.78	$ 1.42	$ 16.32	$ 4.91	$ (6.15)
Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – diluted (in usd per share)	$ 0.77	$ 0.83	$ 8.35	$ 6.43	$ (2.10)	$ 0.82	$ 4.78	$ 1.42	$ 16.29	$ 4.91	$ (6.15)

Related Party Transactions an_2

Related Party Transactions and Major Customers (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Gross premiums written	$ 905,479,000	$ 861,068,000	$ 1,476,908,000	$ 1,564,295,000	$ 547,755,000	$ 625,677,000	$ 977,343,000	$ 1,159,652,000	$ 4,807,750,000	$ 3,310,427,000	$ 2,797,540,000
Gross premiums earned									4,348,261,000	2,779,796,000	2,307,219,000
Acquisition expenses	208,618,000	$ 202,181,000	$ 227,482,000	$ 123,951,000	120,465,000	$ 109,761,000	$ 105,052,000	$ 97,711,000	762,232,000	432,989,000	346,892,000
Net reinsurance costs and recoveries									(1,124,757,000)	(1,458,518,000)	(1,558,960,000)
Total gross reserve for claims and claim expenses	9,384,349,000				6,076,271,000				9,384,349,000	6,076,271,000	5,080,408,000
Ceded premiums written									1,426,257,000	1,178,525,000	926,215,000
Ceded premiums earned									1,414,383,000	1,095,886,000	833,929,000
Reinsurance recoverable	2,791,297,000								2,791,297,000
Equity method investment, dividends and distributions									$ (36,500,000)	$ (26,100,000)	$ 29,700,000
Gross premiums written | Three Brokers
Related Party Transaction [Line Items]
Percent of gross premiums received									79.60%	75.20%	76.40%
Gross premiums written | AON
Related Party Transaction [Line Items]
Percent of gross premiums received									41.70%	40.70%	42.80%
Gross premiums written | Marsh
Related Party Transaction [Line Items]
Percent of gross premiums received									27.10%	24.60%	23.80%
Gross premiums written | Willis Towers Watson
Related Party Transaction [Line Items]
Percent of gross premiums received									10.80%	9.90%	9.80%
Tower Hill Companies
Related Party Transaction [Line Items]
Gross premiums written									$ 39,800,000	$ 45,500,000	$ 39,100,000
Gross premiums earned									40,700,000	43,800,000	35,700,000
Acquisition expenses									6,100,000	7,100,000	5,100,000
Related party receivables	14,800,000				19,300,000				14,800,000	19,300,000
Net reinsurance costs and recoveries									37,700,000	111,200,000	94,400,000
Total gross reserve for claims and claim expenses	71,800,000				$ 98,800,000				71,800,000	98,800,000
Ceded premiums written									500,000
Ceded premiums earned									400,000
Ceded premiums payable	0								0
Policyholder benefits and claims incurred, ceded									0
Policyholder benefits and claims recovered, ceded									41,800,000
Reinsurance recoverable	$ 21,800,000								21,800,000
Equity method investment, dividends and distributions									13,400,000	12,100,000	8,300,000
Top Layer Reinsurance Ltd.
Related Party Transaction [Line Items]
Equity method investment, dividends and distributions									20,000,000	12,500,000	20,000,000
Top Layer Reinsurance Ltd. | Management Fee
Related Party Transaction [Line Items]
Revenue recorded									$ 2,300,000	$ 2,700,000	$ 2,700,000

Taxation (Narrative) (Details)

Taxation (Narrative) (Details) - USD ($)	Dec. 22, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 22, 2019
Operating Loss Carryforwards [Line Items]
Partial write-down of U.S. deferred tax asset pursuant to the Tax Cuts and Jobs Act of 2017	$ 36,700,000
Increase (decrease) in valuation allowance		$ 40,400,000	$ 5,300,000	$ 11,200,000
Income taxes paid		9,749,000	341,000	$ 343,000
Unrecognized tax benefits		0	0
Interest and penalties accrued on unrecognized tax benefits		$ 0	$ 0
Bermuda
Operating Loss Carryforwards [Line Items]
Statutory income tax rate		0.00%
U.S.
Operating Loss Carryforwards [Line Items]
Expected tax rate		5.00%
Foreign statutory income tax rate		21.00%
Operating loss carryforwards		$ 338,600,000
Ireland
Operating Loss Carryforwards [Line Items]
Foreign statutory income tax rate		12.50%
Operating loss carryforwards		$ 5,600,000
U.K.
Operating Loss Carryforwards [Line Items]
Foreign statutory income tax rate		19.00%
Operating loss carryforwards		$ 115,400,000
Singapore
Operating Loss Carryforwards [Line Items]
Foreign statutory income tax rate		17.00%
Operating loss carryforwards		$ 25,400,000
Switzerland
Operating Loss Carryforwards [Line Items]
Foreign statutory income tax rate		21.20%
Operating loss carryforwards		$ 186,600,000
Australia
Operating Loss Carryforwards [Line Items]
Foreign statutory income tax rate		30.00%
TMR
Operating Loss Carryforwards [Line Items]
Deferred tax assets, valuation allowance					$ 35,700,000

Taxation (Income (Loss) Before

Taxation (Income (Loss) Before Income Taxes, Foreign and Domestic) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit)
Income (loss) before taxes	$ 36,885	$ 111,608	$ 458,330	$ 360,659	$ (132,838)	$ 50,280	$ 256,373	$ 88,800	$ 967,482	$ 262,615	$ (328,184)
Bermuda
Income Tax Expense (Benefit)
Domestic									861,068	349,959	(262,827)
U.S.
Income Tax Expense (Benefit)
Foreign									102,724	(56,261)	(11,897)
Australia
Income Tax Expense (Benefit)
Foreign									3,390	0	0
Switzerland
Income Tax Expense (Benefit)
Foreign									14,255	166	0
Ireland
Income Tax Expense (Benefit)
Foreign									(388)	551	617
Singapore
Income Tax Expense (Benefit)
Foreign									(6,334)	(3,226)	(12,421)
U.K.
Income Tax Expense (Benefit)
Foreign									$ (7,233)	$ (28,574)	$ (41,656)

Taxation (Components of Income

Taxation (Components of Income Tax Benefit (Expense)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit)
Current									$ (2,128)	$ (1,668)	$ (844)
Deferred									(15,087)	7,970	(25,643)
Income tax (expense) benefit	$ 3,455	$ (3,664)	$ (9,475)	$ (7,531)	$ 8,852	$ (1,451)	$ (4,506)	$ 3,407	$ (17,215)	$ 6,302	$ (26,487)

Taxation (Income Tax Reconcilia

Taxation (Income Tax Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Expected income tax (expense) benefit									$ (22,874)	$ 17,697	$ 14,216
Nondeductible expenses									(7,059)	(370)	(276)
Change in valuation allowance									(5,481)	(5,255)	(11,718)
Withholding tax									(665)	(1,831)	(216)
Effect of change in tax rate									(262)	(708)	(38,083)
Non-taxable foreign exchange gains (losses)									(4)	586	2,574
Tax exempt income									400	944	3,794
Transfer pricing									2,503	(2,481)	(11)
GAAP to statutory accounting difference									6,553	0	0
Foreign branch adjustments									7,315	0	0
U.S. base erosion and anti-abuse tax									0	(1,271)	0
Other									2,359	(1,009)	3,233
Income tax (expense) benefit	$ 3,455	$ (3,664)	$ (9,475)	$ (7,531)	$ 8,852	$ (1,451)	$ (4,506)	$ 3,407	$ (17,215)	$ 6,302	$ (26,487)

Taxation (Deferred Tax Assets a

Taxation (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Tax loss and credit carryforwards	$ 111,835	$ 60,395
Unearned premiums	14,430	10,108
Deferred finance charges	10,160	14,646
Reserve for claims and claim expenses	8,984	17,345
Accrued expenses	7,196	4,292
Deferred underwriting results	4,033	3,514
Premiums receivable	3,412	0
Investments	0	4,427
Deferred tax assets	160,050	114,727
Deferred tax liabilities
Deferred acquisition expenses	(16,296)	(11,801)
VOBA	(12,673)	0
Investments	(6,468)	0
Intangible assets	(2,891)	0
Amortization and depreciation	(2,133)	(2,992)
Deferred tax liabilities	(40,461)	(14,793)
Net deferred tax asset before valuation allowance	119,589	99,934
Valuation allowance	(75,685)	(35,271)
Net deferred tax asset	$ 43,904	$ 64,663

Segment Reporting (Schedule of

Segment Reporting (Schedule of Significant Components of the Company's Revenues and Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Gross premiums written	$ 905,479	$ 861,068	$ 1,476,908	$ 1,564,295	$ 547,755	$ 625,677	$ 977,343	$ 1,159,652	$ 4,807,750	$ 3,310,427	$ 2,797,540
Net premiums written	725,367	704,130	1,022,965	929,031	411,094	453,255	604,509	663,044	3,381,493	2,131,902	1,871,325
Net premiums earned	970,125	906,748	911,502	550,028	574,613	531,849	429,385	440,282	3,338,403	1,976,129	1,717,575
Net claims and claim expenses incurred	762,093	654,520	453,373	227,035	477,638	410,510	60,167	171,703	2,097,021	1,120,018	1,861,428
Acquisition expenses	208,618	202,181	227,482	123,951	120,465	109,761	105,052	97,711	762,232	432,989	346,892
Operational expenses	64,571	53,415	59,814	44,933	58,859	40,593	37,543	41,272	222,733	178,267	160,778
Underwriting income (loss)									256,417	244,855	(651,523)
Net investment income	112,695	113,844	115,832	81,462	53,338	80,696	71,356	56,476	423,833	261,866	222,209
Net foreign exchange (losses) gains	(1,126)	(8,275)	9,309	(2,846)	(932)	(4,566)	(10,687)	3,757	(2,938)	(12,428)	10,628
Equity in earnings of other ventures	5,874	5,877	6,812	4,661	4,143	7,648	5,826	857	23,224	18,474	8,030
Other income	(160)	1,016	922	3,171	5,489	497	1,225	(1,242)	4,949	5,969	9,415
Net realized and unrealized gains (losses) on investments	17,897	31,938	194,003	170,645	(88,654)	13,630	(17,901)	(82,144)	414,483	(175,069)	135,822
Corporate expenses	(17,642)	(13,844)	(23,847)	(38,789)	(12,108)	(6,841)	(8,301)	(6,733)	(94,122)	(33,983)	(18,572)
Interest expense	(15,496)	(15,580)	(15,534)	(11,754)	(11,765)	(11,769)	(11,768)	(11,767)	(58,364)	(47,069)	(44,193)
Income (loss) before taxes	36,885	111,608	458,330	360,659	(132,838)	50,280	256,373	88,800	967,482	262,615	(328,184)
Income tax (expense) benefit	3,455	(3,664)	(9,475)	(7,531)	8,852	(1,451)	(4,506)	3,407	(17,215)	6,302	(26,487)
Net (income) loss attributable to redeemable noncontrolling interests	2,622	(62,057)	(71,812)	(70,222)	49,269	(6,440)	(54,483)	(29,899)	(201,469)	(41,553)	132,282
Dividends on preference shares	(9,189)	(9,189)	(9,189)	(9,189)	(9,189)	(9,708)	(5,596)	(5,595)	(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders	$ 33,773	$ 36,698	$ 367,854	$ 273,717	$ (83,906)	$ 32,681	$ 191,788	$ 56,713	712,042	197,276	(244,770)
Net claims and claim expenses incurred – current accident year									2,123,876	1,390,767	1,902,424
Net claims and claim expenses incurred – prior accident years									(26,855)	(270,749)	(40,996)
Total net incurred									$ 2,097,021	$ 1,120,018	$ 1,861,428
Net claims and claim expense ratio – current accident year									63.60%	70.40%	110.80%
Net claims and claim expense ratio – prior accident years									(0.80%)	(13.70%)	(2.40%)
Net claims and claim expense ratio – calendar year									62.80%	56.70%	108.40%
Underwriting expense ratio									29.50%	30.90%	29.50%
Combined ratio									92.30%	87.60%	137.90%
Other
Segment Reporting Information [Line Items]
Gross premiums written									$ 0	$ 0	$ (7)
Net premiums written									0	0	4
Net premiums earned									0	0	4
Net claims and claim expenses incurred									(40)	(197)	(1,583)
Acquisition expenses									(207)	(2)	(1)
Operational expenses									(828)	430	36
Underwriting income (loss)									1,075	(231)	1,552
Net investment income									423,833	261,866	222,209
Net foreign exchange (losses) gains									(2,938)	(12,428)	10,628
Equity in earnings of other ventures									23,224	18,474	8,030
Other income									4,949	5,969	9,415
Net realized and unrealized gains (losses) on investments									414,483	(175,069)	135,822
Corporate expenses									(94,122)	(33,983)	(18,572)
Interest expense									(58,364)	(47,069)	(44,193)
Income tax (expense) benefit									(17,215)	6,302	(26,487)
Net (income) loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Dividends on preference shares									(36,756)	(30,088)	(22,381)
Net claims and claim expenses incurred – current accident year									0	0	0
Net claims and claim expenses incurred – prior accident years									(40)	(197)	(1,583)
Total net incurred									(40)	(197)	(1,583)
Property
Segment Reporting Information [Line Items]
Gross premiums written									2,430,985	1,760,926	1,440,437
Net claims and claim expenses incurred – prior accident years									(2,933)	(221,290)	(45,596)
Property | Operating Segments
Segment Reporting Information [Line Items]
Gross premiums written									2,430,985	1,760,926	1,440,437
Net premiums written									1,654,259	1,055,188	978,014
Net premiums earned									1,627,494	1,050,831	931,070
Net claims and claim expenses incurred									965,424	497,895	1,297,985
Acquisition expenses									313,761	177,912	113,816
Operational expenses									139,015	112,954	94,194
Underwriting income (loss)									209,294	262,070	(574,925)
Net claims and claim expenses incurred – current accident year									968,357	719,185	1,343,581
Net claims and claim expenses incurred – prior accident years									(2,933)	(221,290)	(45,596)
Total net incurred									$ 965,424	$ 497,895	$ 1,297,985
Net claims and claim expense ratio – current accident year									59.50%	68.40%	144.30%
Net claims and claim expense ratio – prior accident years									(0.20%)	(21.00%)	(4.90%)
Net claims and claim expense ratio – calendar year									59.30%	47.40%	139.40%
Underwriting expense ratio									27.80%	27.70%	22.30%
Combined ratio									87.10%	75.10%	161.70%
Casualty and Specialty
Segment Reporting Information [Line Items]
Gross premiums written									$ 2,376,765	$ 1,549,501	$ 1,357,110
Net claims and claim expenses incurred – prior accident years									(23,882)	(49,262)	6,183
Casualty and Specialty | Operating Segments
Segment Reporting Information [Line Items]
Gross premiums written									2,376,765	1,549,501	1,357,110
Net premiums written									1,727,234	1,076,714	893,307
Net premiums earned									1,710,909	925,298	786,501
Net claims and claim expenses incurred									1,131,637	622,320	565,026
Acquisition expenses									448,678	255,079	233,077
Operational expenses									84,546	64,883	66,548
Underwriting income (loss)									46,048	(16,984)	(78,150)
Net claims and claim expenses incurred – current accident year									1,155,519	671,582	558,843
Net claims and claim expenses incurred – prior accident years									(23,882)	(49,262)	6,183
Total net incurred									$ 1,131,637	$ 622,320	$ 565,026
Net claims and claim expense ratio – current accident year									67.50%	72.60%	71.10%
Net claims and claim expense ratio – prior accident years									(1.40%)	(5.30%)	0.70%
Net claims and claim expense ratio – calendar year									66.10%	67.30%	71.80%
Underwriting expense ratio									31.20%	34.50%	38.10%
Combined ratio									97.30%	101.80%	109.90%

Segment Reporting (Schedule o_2

Segment Reporting (Schedule of Gross Premiums Written Allocated to the Territory of Coverage Exposure) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written	$ 905,479	$ 861,068	$ 1,476,908	$ 1,564,295	$ 547,755	$ 625,677	$ 977,343	$ 1,159,652	$ 4,807,750	$ 3,310,427	$ 2,797,540
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									0	0	(7)
Property
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									2,430,985	1,760,926	1,440,437
Property | U.S. and Caribbean
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									1,368,205	978,063	954,269
Property | Worldwide
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									643,744	464,311	305,915
Property | Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									182,544	144,857	49,486
Property | Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									90,328	71,601	49,821
Property | Worldwide (excluding U.S.)
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									79,393	66,872	48,182
Property | Australia and New Zealand
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									32,203	19,273	14,151
Property | Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									34,568	15,949	18,613
Casualty and Specialty
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									2,376,765	1,549,501	1,357,110
Casualty and Specialty | U.S. and Caribbean
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									1,071,170	667,125	622,757
Casualty and Specialty | Worldwide
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									935,626	776,976	686,253
Casualty and Specialty | Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									227,178	15,296	9,752
Casualty and Specialty | Worldwide (excluding U.S.)
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									25,291	31,734	10,104
Casualty and Specialty | Australia and New Zealand
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									34,053	3,667	4,141
Casualty and Specialty | Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Gross premiums written									$ 83,447	$ 54,703	$ 24,103

Stock Incentive Compensation _3

Stock Incentive Compensation and Employee Benefit Plans (Narrative) (Details)	12 Months Ended
	Dec. 31, 2019USD ($)dshares	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	May 16, 2016shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares and share units vested	$ 41,600,000	$ 37,200,000	$ 56,900,000
Cash received from exercises of stock options during the period	0	0	0
Excess windfall tax benefit realized by the Company due to its net operating loss position in the taxable jurisdictions in which it operates	200,000	0	0
Total stock compensation expense recognized	41,400,000	35,700,000	37,200,000
Contributions to defined contribution pension plans	4,900,000	$ 4,100,000	$ 4,400,000
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to restricted stock awards	$ 52,600,000
Periods for recognition of compensation costs not yet recognized	1 year 8 months 12 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	3 years
Vesting maximum as a percentage of target if performance goal are achieved	250.00%
Period for average closing share price to determine total shareholder return | d	20
Performance period	1 year
Unrecognized compensation costs related to restricted stock awards	$ 7,700,000
Periods for recognition of compensation costs not yet recognized	1 year 4 months 24 days
Cash Settled Restricted Stock Unit (CSRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	4 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to restricted stock awards	$ 5,400,000
Periods for recognition of compensation costs not yet recognized	10 months 24 days
2016 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares) | shares				1,625,000
Number of shares available for grant (in shares) | shares	1,300,000
2001 Stock Incentive Plan | Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	4 years
Share-based payment award, expiration period	10 years
2001 Stock Incentive Plan and 2016 Long-Term Incentive Plan | Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	4 years
Non-Employee Director Stock Incentive Plan | Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	3 years
2001 Stock Incentive Plan and 2010 Performance Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares) | shares	0

Stock Incentive Compensation _4

Stock Incentive Compensation and Employee Benefit Plans (Schedule of Valuation Assumptions) (Details) - Performance Shares	12 Months Ended
	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	15.80%
Risk free interest rate, minimum	1.85%
Risk free interest rate, maximum	2.36%

Stock Incentive Compensation _5

Stock Incentive Compensation and Employee Benefit Plans (Schedule of Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted options outstanding
Beginning balance (in shares)	32,001	206,795
Options granted (in shares)	0	0
Options forfeited (in shares)	0	0
Options expired (in shares)	0	0
Options exercised (in shares)	(32,001)	(174,794)
Ending balance (in shares)	0	32,001	206,795
Weighted average exercise price
Beginning balance (in usd per share)	$ 53.86	$ 53.17
Options granted (in usd per share)	0	0
Options forfeited (in usd per share)	0	0
Options expired (in usd per share)	0	0
Options exercised (in usd per share)	53.86	53.04
Ending balance (in usd per share)	$ 0	$ 53.86	$ 53.17
Weighted average remaining contractual life	0 years	2 months 12 days	10 months 24 days
Aggregate intrinsic value, Options outstanding	$ 0	$ 2,295	$ 17,174
Aggregate intrinsic value, Options exercised	$ 2,320	$ 15,945
Range of exercise prices, lower range limit (in usd per share)			$ 50.71
Range of exercise prices, upper range limit (in usd per share)			$ 59.66
Range of exercise prices, Options exercised, lower range limit (in usd per share)		$ 50.71
Range of exercise prices, Options exercised, upper range limit (in usd per share)		59.66
Range of exercise prices, Options exercised (in usd per share)	$ 53.86
Range of exercise prices, Total options outstanding (in usd per share)	$ 0	$ 53.86

Stock Incentive Compensation _6

Stock Incentive Compensation and Employee Benefit Plans (Equity Compensation Other than Options) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Settled Restricted Stock Unit (CSRSUs)
Number of shares
Nonvested, beginning balance (in shares)	146,917	262,330	308,344
Awards granted (in shares)	0	0	98,067
Awards vested (in shares)	(80,012)	(108,344)	(122,088)
Awards forfeited (in shares)	(3,161)	(7,069)	(21,993)
Nonvested, ending balance (in shares)	63,744	146,917	262,330
Performance Shares
Number of shares
Nonvested, beginning balance (in shares)	152,451	167,673	211,381
Awards granted (in shares)	58,050	83,475	64,947
Awards vested (in shares)	(21,730)	(16,456)	(62,499)
Awards forfeited (in shares)	(43,924)	(82,241)	(46,156)
Nonvested, ending balance (in shares)	144,847	152,451	167,673
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 57.21	$ 53.11	$ 44.63
Awards granted (in usd per share)	146.10	60.69	65.27
Awards vested (in usd per share)	49.90	53.79	43.51
Nonvested, ending balance (in usd per share)	$ 94.70	$ 57.21	$ 53.11
Employee restricted stock awards
Number of shares
Nonvested, beginning balance (in shares)	447,740	333,037	402,170
Awards granted (in shares)	242,832	255,799	116,345
Awards vested (in shares)	(165,245)	(139,454)	(185,478)
Awards forfeited (in shares)	(14,467)	(1,642)	0
Nonvested, ending balance (in shares)	510,860	447,740	333,037
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 130.37	$ 120.93	$ 103.34
Awards granted (in usd per share)	146.92	132.70	148.66
Awards vested (in usd per share)	124.71	112.70	100.17
Awards forfeited (in usd per share)	136.16	134.38	0
Nonvested, ending balance (in usd per share)	$ 139.91	$ 130.37	$ 120.93
Non-employee director restricted stock awards
Number of shares
Nonvested, beginning balance (in shares)	22,534	20,126	25,545
Awards granted (in shares)	11,444	12,169	12,193
Awards vested (in shares)	(12,972)	(9,761)	(17,612)
Awards forfeited (in shares)	0	0	0
Nonvested, ending balance (in shares)	21,006	22,534	20,126
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 132.29	$ 131.09	$ 107.95
Awards granted (in usd per share)	147.43	127.29	150.05
Awards vested (in usd per share)	131.88	123.59	110.66
Awards forfeited (in usd per share)	0	0	0
Nonvested, ending balance (in usd per share)	$ 140.79	$ 132.29	$ 131.09
Total restricted stock awards
Number of shares
Nonvested, beginning balance (in shares)	470,274	353,163	427,715
Awards granted (in shares)	254,276	267,968	128,538
Awards vested (in shares)	(178,217)	(149,215)	(203,090)
Awards forfeited (in shares)	(14,467)	(1,642)	0
Nonvested, ending balance (in shares)	531,866	470,274	353,163
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 130.46	$ 121.51	$ 103.61
Awards granted (in usd per share)	146.94	132.79	148.79
Awards vested (in usd per share)	125.23	113.41	101.08
Awards forfeited (in usd per share)	136.16	134.38	0
Nonvested, ending balance (in usd per share)	$ 139.94	$ 130.46	$ 121.51

Statutory Requirements (Statuto

Statutory Requirements (Statutory Capital and Surplus) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Bermuda
Statutory Accounting Practices [Line Items]
Statutory capital and surplus	$ 5,325,749	$ 4,366,089
Required statutory capital and surplus	1,201,529	957,650
Unrestricted net assets	1,107,586	931,387
Switzerland
Statutory Accounting Practices [Line Items]
Statutory capital and surplus	580,235	0
Required statutory capital and surplus	465,900	0
Unrestricted net assets	102,943	0
U.S.
Statutory Accounting Practices [Line Items]
Statutory capital and surplus	677,832	502,803
Required statutory capital and surplus	397,447	306,628
Unrestricted net assets	46,630	31,228
U.K.
Statutory Accounting Practices [Line Items]
Statutory capital and surplus	675,864	519,689
Required statutory capital and surplus	675,864	519,689
Unrestricted net assets	$ 0	$ 0

Statutory Requirements (Statu_2

Statutory Requirements (Statutory Net Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Bermuda
Statutory Accounting Practices [Line Items]
Statutory Net Income (Loss)	$ 657,182	$ 326,386	$ (334,142)
Switzerland
Statutory Accounting Practices [Line Items]
Statutory Net Income (Loss)	(14,679)	0	0
U.S.
Statutory Accounting Practices [Line Items]
Statutory Net Income (Loss)	37,827	25,851	(3,627)
U.K.
Statutory Accounting Practices [Line Items]
Statutory Net Income (Loss)	$ (666,595)	$ (6,692)	$ (57,050)

Statutory Requirements (Narrati

Statutory Requirements (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Statutory Accounting Practices [Line Items]
Assets held in trust	$ 7,000,000	$ 5,700,000
U.S.
Statutory Accounting Practices [Line Items]
Unrestricted net assets	46,630	31,228
New York | Multi-Beneficiary Reinsurance Trust | Renaissance Reinsurance Ltd.
Statutory Accounting Practices [Line Items]
Assets held in trust	1,300,000	1,200,000
New York | Multi-Beneficiary Reinsurance Trust | Renaissance Reinsurance Ltd. | Low
Statutory Accounting Practices [Line Items]
Assets held in trust	927,400	1,100,000
New York | Multi-Beneficiary Reinsurance Trust | DaVinci Reinsurance Ltd.
Statutory Accounting Practices [Line Items]
Assets held in trust	336,500	385,800
New York | Multi-Beneficiary Reinsurance Trust | DaVinci Reinsurance Ltd. | Low
Statutory Accounting Practices [Line Items]
Assets held in trust	249,400	356,900
New York | Multi-Beneficiary Reduced Collateral Reinsurance Trust | Renaissance Reinsurance Ltd.
Statutory Accounting Practices [Line Items]
Assets held in trust	51,700	50,300
New York | Multi-Beneficiary Reduced Collateral Reinsurance Trust | Renaissance Reinsurance Ltd. | Low
Statutory Accounting Practices [Line Items]
Assets held in trust	40,300	36,800
New York | Multi-Beneficiary Reduced Collateral Reinsurance Trust | DaVinci Reinsurance Ltd.
Statutory Accounting Practices [Line Items]
Assets held in trust	43,800	63,200
New York | Multi-Beneficiary Reduced Collateral Reinsurance Trust | DaVinci Reinsurance Ltd. | Low
Statutory Accounting Practices [Line Items]
Assets held in trust	$ 40,900	$ 26,900
Florida | Multi-Beneficiary Reduced Collateral Reinsurance Trust | Renaissance Reinsurance Ltd.
Statutory Accounting Practices [Line Items]
Multi-beneficiary reduced collateral reinsurance trust collateral reduction	20.00%
Florida | Multi-Beneficiary Reduced Collateral Reinsurance Trust | RenaissanceRe Europe
Statutory Accounting Practices [Line Items]
Multi-beneficiary reduced collateral reinsurance trust collateral reduction	20.00%
Florida | Multi-Beneficiary Reduced Collateral Reinsurance Trust | DaVinci Reinsurance Ltd.
Statutory Accounting Practices [Line Items]
Multi-beneficiary reduced collateral reinsurance trust collateral reduction	50.00%

Derivative Instruments (Schedul

Derivative Instruments (Schedule of Location on Consolidated Balance Sheets and Fair Value of Principal Derivative Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivative Assets
Gross Amounts of Recognized Assets	$ 28,154	$ 22,874
Gross Amounts Offset in the Balance Sheet	3,829	3,944
Net Amounts of Assets Presented in the Balance Sheet	24,325	18,930
Collateral	3,601	0
Net Amount	20,724	18,930
Derivative Liabilities
Gross Amounts of Recognized Liabilities	8,160	8,225
Gross Amounts Offset in the Balance Sheet	772	1,684
Net Amounts of Liabilities Presented in the Balance Sheet	7,388	6,540
Collateral Pledged	1,473	2,132
Net Amount	5,915	4,408
Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	28,090
Gross Amounts Offset in the Balance Sheet	3,162
Net Amounts of Assets Presented in the Balance Sheet	24,928
Collateral	3,601
Net Amount	21,327
Derivative Liabilities
Gross Amounts of Recognized Liabilities	6,342
Gross Amounts Offset in the Balance Sheet	772
Net Amounts of Liabilities Presented in the Balance Sheet	5,570
Collateral Pledged	1,473
Net Amount	4,097
Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	64
Gross Amounts Offset in the Balance Sheet	667
Net Amounts of Assets Presented in the Balance Sheet	(603)
Collateral	0
Net Amount	(603)
Other assets | Interest rate futures | Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	234	971
Gross Amounts Offset in the Balance Sheet	122	636
Net Amounts of Assets Presented in the Balance Sheet	112	335
Collateral	0	0
Net Amount	112	335
Other assets | Interest rate swaps | Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets		860
Gross Amounts Offset in the Balance Sheet		0
Net Amounts of Assets Presented in the Balance Sheet		860
Collateral		0
Net Amount		860
Other assets | Foreign currency forward contracts | Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	22,702	16,459
Gross Amounts Offset in the Balance Sheet	2,418	2,260
Net Amounts of Assets Presented in the Balance Sheet	20,284	14,199
Collateral	0	0
Net Amount	20,284	14,199
Other assets | Foreign currency forward contracts | Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	1,082	3,194
Gross Amounts Offset in the Balance Sheet	622	71
Net Amounts of Assets Presented in the Balance Sheet	460	3,123
Collateral	0	0
Net Amount	460	3,123
Other assets | Foreign currency forward contracts | Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	64
Gross Amounts Offset in the Balance Sheet	667
Net Amounts of Assets Presented in the Balance Sheet	(603)
Collateral	0
Net Amount	(603)
Other assets | Credit default swaps | Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	37
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of Assets Presented in the Balance Sheet	37
Collateral	0
Net Amount	37
Other assets | Total return swaps | Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	3,744
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of Assets Presented in the Balance Sheet	3,744
Collateral	3,601
Net Amount	143
Other assets | Equity futures | Not Designated as Hedging Instrument
Derivative Assets
Gross Amounts of Recognized Assets	291	1,390
Gross Amounts Offset in the Balance Sheet	0	977
Net Amounts of Assets Presented in the Balance Sheet	291	413
Collateral	0	0
Net Amount	291	413
Other liabilities | Interest rate futures | Not Designated as Hedging Instrument
Derivative Liabilities
Gross Amounts of Recognized Liabilities	1,545	910
Gross Amounts Offset in the Balance Sheet	122	636
Net Amounts of Liabilities Presented in the Balance Sheet	1,423	273
Collateral Pledged	1,423	273
Net Amount	0	0
Other liabilities | Interest rate swaps | Not Designated as Hedging Instrument
Derivative Liabilities
Gross Amounts of Recognized Liabilities	50	506
Gross Amounts Offset in the Balance Sheet	0	0
Net Amounts of Liabilities Presented in the Balance Sheet	50	506
Collateral Pledged	50	254
Net Amount	0	252
Other liabilities | Foreign currency forward contracts | Not Designated as Hedging Instrument
Derivative Liabilities
Gross Amounts of Recognized Liabilities	3,808	4,154
Gross Amounts Offset in the Balance Sheet	28	0
Net Amounts of Liabilities Presented in the Balance Sheet	3,780	4,154
Collateral Pledged	0	0
Net Amount	3,780	4,154
Other liabilities | Foreign currency forward contracts | Not Designated as Hedging Instrument
Derivative Liabilities
Gross Amounts of Recognized Liabilities	939	72
Gross Amounts Offset in the Balance Sheet	622	71
Net Amounts of Liabilities Presented in the Balance Sheet	317	1
Collateral Pledged	0	0
Net Amount	317	1
Other liabilities | Foreign currency forward contracts | Designated as Hedging Instrument
Derivative Liabilities
Gross Amounts of Recognized Liabilities	1,818
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of Liabilities Presented in the Balance Sheet	1,818
Collateral Pledged	0
Net Amount	$ 1,818
Other liabilities | Credit default swaps | Not Designated as Hedging Instrument
Derivative Liabilities
Gross Amounts of Recognized Liabilities		1,606
Gross Amounts Offset in the Balance Sheet		0
Net Amounts of Liabilities Presented in the Balance Sheet		1,606
Collateral Pledged		1,605
Net Amount		1
Other liabilities | Equity futures | Not Designated as Hedging Instrument
Derivative Liabilities
Gross Amounts of Recognized Liabilities		977
Gross Amounts Offset in the Balance Sheet		977
Net Amounts of Liabilities Presented in the Balance Sheet		0
Collateral Pledged		0
Net Amount		$ 0

Derivative Instruments (Sched_2

Derivative Instruments (Schedule of Gain (Loss) Recognized in Consolidated Statements of Operations Related to Principal Derivative Instruments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	$ 70,862	$ 11,980	$ 6,222
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	69,903	11,980	6,222
Foreign currency forward contracts | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Accumulated other comprehensive income (loss)	959	0	0
Net realized and unrealized (losses) gains on investments | Interest rate futures | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	16,848	6,109	(3,252)
Net realized and unrealized (losses) gains on investments | Interest rate swaps | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	1,488	(84)	436
Net realized and unrealized (losses) gains on investments | Credit default swaps | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	7,043	(3,106)	326
Net realized and unrealized (losses) gains on investments | Total return swaps | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	12,155	0	0
Net realized and unrealized (losses) gains on investments | Equity futures | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	21,357	(515)	0
Net foreign exchange (losses) gains | Foreign currency forward contracts | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	12,617	3,840	9,628
Net foreign exchange (losses) gains | Foreign currency forward contracts | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	$ (1,605)	$ 5,736	$ (916)

Derivative Instruments (Narrati

Derivative Instruments (Narrative) (Details) - Not Designated as Hedging Instrument - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Interest rate swaps | Paying a Fixed Rate | United States of America, Dollars
Derivative [Line Items]
Derivative, notional amount	$ 27,900,000	$ 78,400,000
Interest rate swaps | Receiving a Fixed Rate | United States of America, Dollars
Derivative [Line Items]
Derivative, notional amount	25,500,000	32,100,000
Long | Interest rate futures
Derivative [Line Items]
Derivative, notional amount	2,500,000,000	1,900,000,000
Long | Foreign currency forward contracts
Derivative [Line Items]
Derivative, notional amount	722,600,000	354,100,000
Long | Foreign currency forward contracts
Derivative [Line Items]
Derivative, notional amount	195,600,000	121,300,000
Long | Credit default swaps
Derivative [Line Items]
Derivative, notional amount	500,000	1,000,000
Long | Total return swaps
Derivative [Line Items]
Derivative, notional amount	173,500,000
Long | Equity futures
Derivative [Line Items]
Derivative, notional amount	122,000,000	44,700,000
Short | Interest rate futures
Derivative [Line Items]
Derivative, notional amount	1,000,000,000	545,800,000
Short | Foreign currency forward contracts
Derivative [Line Items]
Derivative, notional amount	1,200,000,000	601,200,000
Short | Foreign currency forward contracts
Derivative [Line Items]
Derivative, notional amount	61,000,000	42,900,000
Short | Credit default swaps
Derivative [Line Items]
Derivative, notional amount	143,400,000	126,200,000
Short | Total return swaps
Derivative [Line Items]
Derivative, notional amount	0
Short | Equity futures
Derivative [Line Items]
Derivative, notional amount	$ 0	$ 0

Derivative Instruments (Sched_3

Derivative Instruments (Schedule of Derivative Instruments Designated as Hedges of a Net Investment in a Foreign Operation) (Details) - Foreign Exchange Forward - Designated as Hedging Instrument - Net Investment Hedging - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Weighted average of U.S. dollar equivalent of foreign denominated net assets	$ 81,264	$ 0
Derivative gains	$ 959	$ 0

Commitments, Contingencies an_3

Commitments, Contingencies and Other Items (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Commitments and Contingencies [Line Items]
Initial commitments	$ 1,100,000,000
Fulfilled commitments	708,400,000
Unfunded commitments	$ 411,300,000
Operating lease, weighted average lease term	4 years
Operating lease, right-of-use asset	$ 42,800,000
Operating lease, liability	42,900,000
Operating lease, expense	$ 8,500,000
Operating lease, expense		$ 6,100,000
Lessee, finance lease, term of contract	20 years
Lessee, finance lease, renewal term	30 years
Letter of Credit
Commitments and Contingencies [Line Items]
Letters of credit outstanding	$ 1,100,000,000
Letter of Credit | Top Layer Reinsurance Ltd.
Commitments and Contingencies [Line Items]
Collateral pledged to support letter of credit	37,500,000
Letter of Credit | Capital Support Agreement | Top Layer Reinsurance Ltd.
Commitments and Contingencies [Line Items]
Maximum mandatory capital contribution in the event of loss that reduced capital and surplus below specified level	$ 50,000,000
Investments as a Percentage of Shareholders' Equity
Commitments and Contingencies [Line Items]
Concentration risk percentage	10.00%
Other assets
Commitments and Contingencies [Line Items]
Finance lease, right-of-use asset	$ 19,800,000	20,600,000
Other liabilities
Commitments and Contingencies [Line Items]
Finance lease, liability	25,100,000	25,600,000
Other Income
Commitments and Contingencies [Line Items]
Finance lease, interest expense	2,600,000	2,600,000
Finance lease, right-of-use asset, amortization	$ 900,000	$ 900,000

Commitments, Contingencies an_4

Commitments, Contingencies and Other Items (Schedule of Future Minimum Payments, Operating and Finance Leases) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Operating leases
2020	$ 7,912
2021	7,684
2022	6,967
2023	3,959
2024	2,850
After 2024	11,285
Future minimum lease payments under existing leases	40,657
Finance leases
2020	3,336
2021	3,336
2022	3,336
2023	2,830
2024	2,661
After 2024	10,129
Future minimum lease payments under existing leases	$ 25,628

Quarterly Financial Informati_3

Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues
Gross premiums written	$ 905,479	$ 861,068	$ 1,476,908	$ 1,564,295	$ 547,755	$ 625,677	$ 977,343	$ 1,159,652	$ 4,807,750	$ 3,310,427	$ 2,797,540
Net premiums written	725,367	704,130	1,022,965	929,031	411,094	453,255	604,509	663,044	3,381,493	2,131,902	1,871,325
(Increase) decrease in unearned premiums	244,758	202,618	(111,463)	(379,003)	163,519	78,594	(175,124)	(222,762)	(43,090)	(155,773)	(153,750)
Net premiums earned (Note 7)	970,125	906,748	911,502	550,028	574,613	531,849	429,385	440,282	3,338,403	1,976,129	1,717,575
Net investment income	112,695	113,844	115,832	81,462	53,338	80,696	71,356	56,476	423,833	261,866	222,209
Net foreign exchange (losses) gains	(1,126)	(8,275)	9,309	(2,846)	(932)	(4,566)	(10,687)	3,757	(2,938)	(12,428)	10,628
Equity in earnings of other ventures	5,874	5,877	6,812	4,661	4,143	7,648	5,826	857	23,224	18,474	8,030
Other income	(160)	1,016	922	3,171	5,489	497	1,225	(1,242)	4,949	5,969	9,415
Net realized and unrealized gains (losses) on investments	17,897	31,938	194,003	170,645	(88,654)	13,630	(17,901)	(82,144)	414,483	(175,069)	135,822
Total revenues	1,105,305	1,051,148	1,238,380	807,121	547,997	629,754	479,204	417,986	4,201,954	2,074,941	2,103,679
Expenses
Net claims and claim expenses incurred	762,093	654,520	453,373	227,035	477,638	410,510	60,167	171,703	2,097,021	1,120,018	1,861,428
Acquisition costs	208,618	202,181	227,482	123,951	120,465	109,761	105,052	97,711	762,232	432,989	346,892
Operational expenses	64,571	53,415	59,814	44,933	58,859	40,593	37,543	41,272	222,733	178,267	160,778
Corporate expenses	17,642	13,844	23,847	38,789	12,108	6,841	8,301	6,733	94,122	33,983	18,572
Interest expense	15,496	15,580	15,534	11,754	11,765	11,769	11,768	11,767	58,364	47,069	44,193
Total expenses	1,068,420	939,540	780,050	446,462	680,835	579,474	222,831	329,186	3,234,472	1,812,326	2,431,863
Income (loss) before taxes	36,885	111,608	458,330	360,659	(132,838)	50,280	256,373	88,800	967,482	262,615	(328,184)
Income tax (expense) benefit	3,455	(3,664)	(9,475)	(7,531)	8,852	(1,451)	(4,506)	3,407	(17,215)	6,302	(26,487)
Net income (loss)	40,340	107,944	448,855	353,128	(123,986)	48,829	251,867	92,207	950,267	268,917	(354,671)
Net (income) loss attributable to redeemable noncontrolling interests	2,622	(62,057)	(71,812)	(70,222)	49,269	(6,440)	(54,483)	(29,899)	(201,469)	(41,553)	132,282
Net income (loss) attributable to RenaissanceRe	42,962	45,887	377,043	282,906	(74,717)	42,389	197,384	62,308	748,798	227,364	(222,389)
Dividends on preference shares	(9,189)	(9,189)	(9,189)	(9,189)	(9,189)	(9,708)	(5,596)	(5,595)	(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders	$ 33,773	$ 36,698	$ 367,854	$ 273,717	$ (83,906)	$ 32,681	$ 191,788	$ 56,713	$ 712,042	$ 197,276	$ (244,770)
Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – basic (in usd per share)	$ 0.77	$ 0.83	$ 8.36	$ 6.43	$ (2.10)	$ 0.82	$ 4.78	$ 1.42	$ 16.32	$ 4.91	$ (6.15)
Net income (loss) available (attributable) to RenaissanceRe common shareholders per common share – diluted (in usd per share)	$ 0.77	$ 0.83	$ 8.35	$ 6.43	$ (2.10)	$ 0.82	$ 4.78	$ 1.42	$ 16.29	$ 4.91	$ (6.15)
Average shares outstanding - basic (in shares)	43,467	43,462	43,483	42,065	40,111	39,624	39,641	39,552	43,119	39,732	39,854
Average shares outstanding - diluted (in shares)	43,552	43,537	43,521	42,091	40,111	39,637	39,654	39,599	43,175	39,755	39,854

Condensed Consolidating Finan_3

Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries (Condensed Consolidating Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets
Total investments	$ 17,368,789	$ 11,885,747
Cash and cash equivalents	1,379,068	1,107,922
Investments in subsidiaries	0	0
Due from subsidiaries and affiliates	0	0
Premiums receivable	2,599,896	1,537,188
Prepaid reinsurance premiums	767,781	616,185
Reinsurance recoverable	2,791,297	2,372,221	$ 1,586,630
Accrued investment income	72,461	51,311
Deferred acquisition costs and value of business acquired	663,991	476,661
Receivable for investments sold	78,369	256,416
Other assets	346,216	135,127
Goodwill and other intangible assets	262,226	237,418
Total assets	26,330,094	18,676,196
Liabilities
Reserve for claims and claim expenses (Note 8)	9,384,349	6,076,271	5,080,408
Unearned premiums	2,530,975	1,716,021
Debt (Note 9)	1,384,105	991,127
Amounts due to subsidiaries and affiliates	0	0
Reinsurance balances payable	2,830,691	1,902,056
Payable for investments purchased	225,275	380,332
Other liabilities	932,024	513,609
Total liabilities	17,287,419	11,579,416
Redeemable noncontrolling interests	3,071,308	2,051,700
Shareholders’ Equity
Total shareholders’ equity	5,971,367	5,045,080	$ 4,391,375
Total liabilities, noncontrolling interests and shareholders’ equity	26,330,094	18,676,196
RenaissanceRe Holdings Ltd. (Parent Guarantor)
Assets
Cash and cash equivalents	26,460	3,534
Investments in subsidiaries	5,204,260	4,414,475
Accrued investment income	0	1,046
Receivable for investments sold	173	203
Other assets	847,406	458,842
Goodwill and other intangible assets	116,212	120,476
Total assets	6,395,687	5,368,975
Liabilities
Amounts due to subsidiaries and affiliates	6,708	6,453
Other liabilities	26,137	17,442
Total liabilities	424,320	323,895
Shareholders’ Equity
Total shareholders’ equity	5,971,367	5,045,080
Total liabilities, noncontrolling interests and shareholders’ equity	6,395,687	5,368,975
Reportable Legal Entities | RenaissanceRe Holdings Ltd. (Parent Guarantor)
Assets
Total investments	190,451	313,360
Cash and cash equivalents	26,460	3,534
Investments in subsidiaries	5,204,260	4,414,475
Due from subsidiaries and affiliates	10,725	57,039
Premiums receivable	0	0
Prepaid reinsurance premiums	0	0
Reinsurance recoverable	0	0
Accrued investment income	0	1,046
Deferred acquisition costs and value of business acquired	0	0
Receivable for investments sold	173	203
Other assets	847,406	458,842
Goodwill and other intangible assets	116,212	120,476
Total assets	6,395,687	5,368,975
Liabilities
Reserve for claims and claim expenses (Note 8)	0	0
Unearned premiums	0	0
Debt (Note 9)	391,475	300,000
Amounts due to subsidiaries and affiliates	6,708	6,453
Reinsurance balances payable	0	0
Payable for investments purchased	0	0
Other liabilities	26,137	17,442
Total liabilities	424,320	323,895
Redeemable noncontrolling interests	0	0
Shareholders’ Equity
Total shareholders’ equity	5,971,367	5,045,080
Total liabilities, noncontrolling interests and shareholders’ equity	6,395,687	5,368,975
Reportable Legal Entities | Other RenaissanceRe Holdings Ltd. Subsidiaries And Eliminations (Non-Guarantor Subsidiaries)
Assets
Total investments	16,766,409	11,465,660
Cash and cash equivalents	1,334,437	1,091,434
Investments in subsidiaries	0	0
Due from subsidiaries and affiliates	0	0
Premiums receivable	2,599,896	1,537,188
Prepaid reinsurance premiums	767,781	616,185
Reinsurance recoverable	2,791,297	2,372,221
Accrued investment income	71,020	49,828
Deferred acquisition costs and value of business acquired	663,991	476,661
Receivable for investments sold	78,196	232,328
Other assets	301,578	(1,403,636)
Goodwill and other intangible assets	146,014	116,942
Total assets	25,520,619	16,554,811
Liabilities
Reserve for claims and claim expenses (Note 8)	9,384,349	6,076,271
Unearned premiums	2,530,975	1,716,021
Debt (Note 9)	148,349	148,041
Amounts due to subsidiaries and affiliates	0	0
Reinsurance balances payable	2,830,691	1,902,056
Payable for investments purchased	225,275	380,308
Other liabilities	899,682	482,422
Total liabilities	16,019,321	10,705,119
Redeemable noncontrolling interests	3,071,308	2,051,700
Shareholders’ Equity
Total shareholders’ equity	6,429,990	3,797,992
Total liabilities, noncontrolling interests and shareholders’ equity	25,520,619	16,554,811
Reportable Legal Entities | RenRe North America Holdings Inc. (Subsidiary Issuer)
Assets
Total investments	123,792	77,842
Cash and cash equivalents	9,440	3,350
Investments in subsidiaries	48,247	58,458
Due from subsidiaries and affiliates	101,579	101,579
Premiums receivable	0	0
Prepaid reinsurance premiums	0	0
Reinsurance recoverable	0	0
Accrued investment income	270	310
Deferred acquisition costs and value of business acquired	0	0
Receivable for investments sold	0	23,885
Other assets	10,978	22,571
Goodwill and other intangible assets	0	0
Total assets	294,306	287,995
Liabilities
Reserve for claims and claim expenses (Note 8)	0	0
Unearned premiums	0	0
Debt (Note 9)	0	0
Amounts due to subsidiaries and affiliates	51	217
Reinsurance balances payable	0	0
Payable for investments purchased	0	24
Other liabilities	278	5,362
Total liabilities	329	5,603
Redeemable noncontrolling interests	0	0
Shareholders’ Equity
Total shareholders’ equity	293,977	282,392
Total liabilities, noncontrolling interests and shareholders’ equity	294,306	287,995
Reportable Legal Entities | RenaissanceRe Finance, Inc. (Subsidiary Issuer)
Assets
Total investments	288,137	28,885
Cash and cash equivalents	8,731	9,604
Investments in subsidiaries	1,426,838	1,215,663
Due from subsidiaries and affiliates	0	0
Premiums receivable	0	0
Prepaid reinsurance premiums	0	0
Reinsurance recoverable	0	0
Accrued investment income	1,171	127
Deferred acquisition costs and value of business acquired	0	0
Receivable for investments sold	0	0
Other assets	12,211	313,636
Goodwill and other intangible assets	0	0
Total assets	1,737,088	1,567,915
Liabilities
Reserve for claims and claim expenses (Note 8)	0	0
Unearned premiums	0	0
Debt (Note 9)	970,255	843,086
Amounts due to subsidiaries and affiliates	102,493	102,243
Reinsurance balances payable	0	0
Payable for investments purchased	0	0
Other liabilities	14,162	13,918
Total liabilities	1,086,910	959,247
Redeemable noncontrolling interests	0	0
Shareholders’ Equity
Total shareholders’ equity	650,178	608,668
Total liabilities, noncontrolling interests and shareholders’ equity	1,737,088	1,567,915
Consolidating Adjustments
Assets
Total investments	0	0
Cash and cash equivalents	0	0
Investments in subsidiaries	(6,679,345)	(5,688,596)
Due from subsidiaries and affiliates	(112,304)	(158,618)
Premiums receivable	0	0
Prepaid reinsurance premiums	0	0
Reinsurance recoverable	0	0
Accrued investment income	0	0
Deferred acquisition costs and value of business acquired	0	0
Receivable for investments sold	0	0
Other assets	(825,957)	743,714
Goodwill and other intangible assets	0	0
Total assets	(7,617,606)	(5,103,500)
Liabilities
Reserve for claims and claim expenses (Note 8)	0	0
Unearned premiums	0	0
Debt (Note 9)	(125,974)	(300,000)
Amounts due to subsidiaries and affiliates	(109,252)	(108,913)
Reinsurance balances payable	0	0
Payable for investments purchased	0	0
Other liabilities	(8,235)	(5,535)
Total liabilities	(243,461)	(414,448)
Redeemable noncontrolling interests	0	0
Shareholders’ Equity
Total shareholders’ equity	(7,374,145)	(4,689,052)
Total liabilities, noncontrolling interests and shareholders’ equity	$ (7,617,606)	$ (5,103,500)

Condensed Consolidating Finan_4

Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries (Condensed Consolidating Statement of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues
Net premiums earned	$ 970,125	$ 906,748	$ 911,502	$ 550,028	$ 574,613	$ 531,849	$ 429,385	$ 440,282	$ 3,338,403	$ 1,976,129	$ 1,717,575
Net investment income	112,695	113,844	115,832	81,462	53,338	80,696	71,356	56,476	423,833	261,866	222,209
Net foreign exchange (losses) gains	(1,126)	(8,275)	9,309	(2,846)	(932)	(4,566)	(10,687)	3,757	(2,938)	(12,428)	10,628
Equity in earnings of other ventures	5,874	5,877	6,812	4,661	4,143	7,648	5,826	857	23,224	18,474	8,030
Other loss	(160)	1,016	922	3,171	5,489	497	1,225	(1,242)	4,949	5,969	9,415
Net realized and unrealized gains (losses) on investments	17,897	31,938	194,003	170,645	(88,654)	13,630	(17,901)	(82,144)	414,483	(175,069)	135,822
Total revenues	1,105,305	1,051,148	1,238,380	807,121	547,997	629,754	479,204	417,986	4,201,954	2,074,941	2,103,679
Expenses
Net claims and claim expenses incurred	762,093	654,520	453,373	227,035	477,638	410,510	60,167	171,703	2,097,021	1,120,018	1,861,428
Acquisition expenses	208,618	202,181	227,482	123,951	120,465	109,761	105,052	97,711	762,232	432,989	346,892
Operational expenses	64,571	53,415	59,814	44,933	58,859	40,593	37,543	41,272	222,733	178,267	160,778
Corporate expenses	17,642	13,844	23,847	38,789	12,108	6,841	8,301	6,733	94,122	33,983	18,572
Interest expense	15,496	15,580	15,534	11,754	11,765	11,769	11,768	11,767	58,364	47,069	44,193
Total expenses	1,068,420	939,540	780,050	446,462	680,835	579,474	222,831	329,186	3,234,472	1,812,326	2,431,863
(Loss) income before equity in net (loss) income of subsidiaries and taxes									967,482	262,615	(328,184)
Equity in net income of subsidiaries									0	0	0
Income (loss) before taxes	36,885	111,608	458,330	360,659	(132,838)	50,280	256,373	88,800	967,482	262,615	(328,184)
Income tax (expense) benefit	3,455	(3,664)	(9,475)	(7,531)	8,852	(1,451)	(4,506)	3,407	(17,215)	6,302	(26,487)
Net income (loss)	40,340	107,944	448,855	353,128	(123,986)	48,829	251,867	92,207	950,267	268,917	(354,671)
Net (income) loss attributable to redeemable noncontrolling interests	2,622	(62,057)	(71,812)	(70,222)	49,269	(6,440)	(54,483)	(29,899)	(201,469)	(41,553)	132,282
Net income (loss) attributable to RenaissanceRe	42,962	45,887	377,043	282,906	(74,717)	42,389	197,384	62,308	748,798	227,364	(222,389)
Dividends on preference shares	(9,189)	(9,189)	(9,189)	(9,189)	(9,189)	(9,708)	(5,596)	(5,595)	(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders	$ 33,773	$ 36,698	$ 367,854	$ 273,717	$ (83,906)	$ 32,681	$ 191,788	$ 56,713	712,042	197,276	(244,770)
RenaissanceRe Holdings Ltd. (Parent Guarantor)
Revenues
Net investment income									39,629	24,791	23,109
Net foreign exchange (losses) gains									7,342	(3)	(1)
Net realized and unrealized gains (losses) on investments									12,393	633	(1,357)
Total revenues									59,364	25,421	21,751
Expenses
Operational expenses									7,506	7,679	11,314
Corporate expenses									58,393	25,190	18,546
Interest expense									18,086	5,683	1,572
Total expenses									83,985	38,552	31,432
(Loss) income before equity in net (loss) income of subsidiaries and taxes									(24,621)	(13,131)	(9,681)
Equity in net income of subsidiaries									773,419	240,495	(212,708)
Net income (loss) attributable to RenaissanceRe									748,798	227,364	(222,389)
Dividends on preference shares									(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders									712,042	197,276	(244,770)
Reportable Legal Entities | RenaissanceRe Holdings Ltd. (Parent Guarantor)
Revenues
Net premiums earned									0	0	0
Net investment income									39,629	24,791	23,109
Net foreign exchange (losses) gains									7,342	(3)	(1)
Equity in earnings of other ventures									0	0	0
Other loss									0	0	0
Net realized and unrealized gains (losses) on investments									12,393	633	(1,357)
Total revenues									59,364	25,421	21,751
Expenses
Net claims and claim expenses incurred									0	0	0
Acquisition expenses									0	0	0
Operational expenses									7,506	7,679	11,314
Corporate expenses									58,393	25,190	18,546
Interest expense									18,086	5,683	1,572
Total expenses									83,985	38,552	31,432
(Loss) income before equity in net (loss) income of subsidiaries and taxes									(24,621)	(13,131)	(9,681)
Equity in net income of subsidiaries									773,419	240,495	(212,708)
Income (loss) before taxes									748,798	227,364	(222,389)
Income tax (expense) benefit									0	0	0
Net income (loss)									748,798	227,364	(222,389)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Net income (loss) attributable to RenaissanceRe									748,798	227,364	(222,389)
Dividends on preference shares									(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders									712,042	197,276	(244,770)
Reportable Legal Entities | Other RenaissanceRe Holdings Ltd. Subsidiaries And Eliminations (Non-Guarantor Subsidiaries)
Revenues
Net premiums earned									3,338,403	1,976,129	1,717,575
Net investment income									419,502	261,192	219,490
Net foreign exchange (losses) gains									(10,280)	(12,425)	10,629
Equity in earnings of other ventures									19,338	15,409	8,253
Other loss									4,949	5,969	9,415
Net realized and unrealized gains (losses) on investments									380,382	(171,013)	123,121
Total revenues									4,152,294	2,075,261	2,088,483
Expenses
Net claims and claim expenses incurred									2,097,021	1,120,018	1,861,428
Acquisition expenses									762,232	432,989	346,892
Operational expenses									207,981	164,605	141,572
Corporate expenses									43,413	3,103	26
Interest expense									2,285	4,367	10,075
Total expenses									3,112,932	1,725,082	2,359,993
(Loss) income before equity in net (loss) income of subsidiaries and taxes									1,039,362	350,179	(271,510)
Equity in net income of subsidiaries									0	0	0
Income (loss) before taxes									1,039,362	350,179	(271,510)
Income tax (expense) benefit									(18,853)	(399)	(14,328)
Net income (loss)									1,020,509	349,780	(285,838)
Net (income) loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Net income (loss) attributable to RenaissanceRe									819,040	308,227	(153,556)
Dividends on preference shares									0	0	0
Net income (loss) available (attributable) to RenaissanceRe common shareholders									819,040	308,227	(153,556)
Reportable Legal Entities | RenRe North America Holdings Inc. (Subsidiary Issuer)
Revenues
Net premiums earned									0	0	0
Net investment income									2,318	2,193	1,947
Net foreign exchange (losses) gains									0	0	0
Equity in earnings of other ventures									0	0	0
Other loss									0	0	0
Net realized and unrealized gains (losses) on investments									21,557	(4,360)	9,621
Total revenues									23,875	(2,167)	11,568
Expenses
Net claims and claim expenses incurred									0	0	0
Acquisition expenses									0	0	0
Operational expenses									56	110	103
Corporate expenses									0	0	0
Interest expense									0	0	0
Total expenses									56	110	103
(Loss) income before equity in net (loss) income of subsidiaries and taxes									23,819	(2,277)	11,465
Equity in net income of subsidiaries									5,611	5,631	756
Income (loss) before taxes									29,430	3,354	12,221
Income tax (expense) benefit									(4,872)	582	(18,147)
Net income (loss)									24,558	3,936	(5,926)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Net income (loss) attributable to RenaissanceRe									24,558	3,936	(5,926)
Dividends on preference shares									0	0	0
Net income (loss) available (attributable) to RenaissanceRe common shareholders									24,558	3,936	(5,926)
Reportable Legal Entities | Platinum Underwriters Finance, Inc. (Subsidiary Issuer)
Revenues
Net premiums earned											0
Net investment income											1,373
Net foreign exchange (losses) gains											0
Equity in earnings of other ventures											0
Other loss											0
Net realized and unrealized gains (losses) on investments											4,916
Total revenues											6,289
Expenses
Net claims and claim expenses incurred											0
Acquisition expenses											0
Operational expenses											85
Corporate expenses											0
Interest expense											2,461
Total expenses											2,546
(Loss) income before equity in net (loss) income of subsidiaries and taxes											3,743
Equity in net income of subsidiaries											28,028
Income (loss) before taxes											31,771
Income tax (expense) benefit											(1,175)
Net income (loss)											30,596
Net (income) loss attributable to redeemable noncontrolling interests											0
Net income (loss) attributable to RenaissanceRe											30,596
Dividends on preference shares											0
Net income (loss) available (attributable) to RenaissanceRe common shareholders											30,596
Reportable Legal Entities | RenaissanceRe Finance, Inc. (Subsidiary Issuer)
Revenues
Net premiums earned									0	0	0
Net investment income									7,547	6,219	3,090
Net foreign exchange (losses) gains									0	0	0
Equity in earnings of other ventures									3,886	3,065	(223)
Other loss									0	0	0
Net realized and unrealized gains (losses) on investments									151	(329)	(479)
Total revenues									11,584	8,955	2,388
Expenses
Net claims and claim expenses incurred									0	0	0
Acquisition expenses									0	0	0
Operational expenses									38,487	34,534	26,063
Corporate expenses									16	7	0
Interest expense									37,993	37,019	31,657
Total expenses									76,496	71,560	57,720
(Loss) income before equity in net (loss) income of subsidiaries and taxes									(64,912)	(62,605)	(55,332)
Equity in net income of subsidiaries									99,148	9,091	9,298
Income (loss) before taxes									34,236	(53,514)	(46,034)
Income tax (expense) benefit									6,510	6,119	7,163
Net income (loss)									40,746	(47,395)	(38,871)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Net income (loss) attributable to RenaissanceRe									40,746	(47,395)	(38,871)
Dividends on preference shares									0	0	0
Net income (loss) available (attributable) to RenaissanceRe common shareholders									40,746	(47,395)	(38,871)
Consolidating Adjustments
Revenues
Net premiums earned									0	0	0
Net investment income									(45,163)	(32,529)	(26,800)
Net foreign exchange (losses) gains									0	0	0
Equity in earnings of other ventures									0	0	0
Other loss									0	0	0
Net realized and unrealized gains (losses) on investments									0	0	0
Total revenues									(45,163)	(32,529)	(26,800)
Expenses
Net claims and claim expenses incurred									0	0	0
Acquisition expenses									0	0	0
Operational expenses									(31,297)	(28,661)	(18,359)
Corporate expenses									(7,700)	5,683	0
Interest expense									0	0	(1,572)
Total expenses									(38,997)	(22,978)	(19,931)
(Loss) income before equity in net (loss) income of subsidiaries and taxes									(6,166)	(9,551)	(6,869)
Equity in net income of subsidiaries									(878,178)	(255,217)	174,626
Income (loss) before taxes									(884,344)	(264,768)	167,757
Income tax (expense) benefit									0	0	0
Net income (loss)									(884,344)	(264,768)	167,757
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Net income (loss) attributable to RenaissanceRe									(884,344)	(264,768)	167,757
Dividends on preference shares									0	0	0
Net income (loss) available (attributable) to RenaissanceRe common shareholders									$ (884,344)	$ (264,768)	$ 167,757

Condensed Consolidating Finan_5

Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries (Condensed Consolidating Statement of Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ 40,340	$ 107,944	$ 448,855	$ 353,128	$ (123,986)	$ 48,829	$ 251,867	$ 92,207	$ 950,267	$ 268,917	$ (354,671)
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)	0	0
Comprehensive income (loss)									949,761	267,260	(355,580)
Net (income) loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive income (loss) attributable to RenaissanceRe									748,292	225,707	(223,298)
RenaissanceRe Holdings Ltd. (Parent Guarantor)
Condensed Financial Statements, Captions [Line Items]
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)	0		$ 0
Comprehensive income (loss)									748,292	225,707	(223,298)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									748,292	225,707	(223,298)
Reportable Legal Entities | RenaissanceRe Holdings Ltd. (Parent Guarantor)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									748,798	227,364	(222,389)
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)
Comprehensive income (loss) attributable to RenaissanceRe									748,292	225,707	(223,298)
Reportable Legal Entities | Other RenaissanceRe Holdings Ltd. Subsidiaries And Eliminations (Non-Guarantor Subsidiaries)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									1,020,509	349,780	(285,838)
Change in net unrealized gains on investments, net of tax									0	0	0
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									1,020,509	349,780	(285,838)
Net (income) loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive income (loss) attributable to RenaissanceRe									819,040	308,227	(153,556)
Reportable Legal Entities | RenRe North America Holdings Inc. (Subsidiary Issuer)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									24,558	3,936	(5,926)
Change in net unrealized gains on investments, net of tax									528	(160)	(89)
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									25,086	3,776	(6,015)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									25,086	3,776	(6,015)
Reportable Legal Entities | Platinum Underwriters Finance, Inc. (Subsidiary Issuer)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)											30,596
Change in net unrealized gains on investments, net of tax											0
Comprehensive income (loss)											30,596
Net (income) loss attributable to redeemable noncontrolling interests											0
Comprehensive loss attributable to redeemable noncontrolling interests											0
Comprehensive income (loss) attributable to RenaissanceRe											30,596
Reportable Legal Entities | RenaissanceRe Finance, Inc. (Subsidiary Issuer)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									40,746	(47,395)	(38,871)
Change in net unrealized gains on investments, net of tax									764	(162)	(89)
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									41,510	(47,557)	(38,960)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									41,510	(47,557)	(38,960)
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									(884,344)	(264,768)	167,757
Change in net unrealized gains on investments, net of tax									(1,292)	322	178
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									(885,636)	(264,446)	167,935
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									$ (885,636)	$ (264,446)	$ 167,935

Condensed Consolidating Finan_6

Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries (Condensed Consolidating Statement of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows (used in) provided by operating activities
Net cash provided by operating activities	$ 2,137,195	$ 1,221,701	$ 1,025,787
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	17,313,940	11,585,576	9,490,669
Purchases of fixed maturity investments trading	(17,919,343)	(12,489,972)	(10,093,532)
Net (purchases) sales of equity investments trading	(7,841)	14,156	115,837
Net sales (purchases) of short term investments	(1,900,741)	(1,436,389)	364,011
Net purchases of other investments	(202,878)	(199,475)	(19,419)
Net purchases of investments in other ventures	(2,717)	(21,473)	0
Return of investment from investment in other ventures	11,250	8,464	20,000
Net (purchases) sales of other assets	(4,108)	2,500	0
Dividends and return of capital from subsidiaries	0	0	0
Contributions to subsidiaries	0	0	0
Due to (from) subsidiaries	0	0	0
Net purchase of TMR	(276,206)	0	0
Net cash used in investing activities	(2,988,644)	(2,536,613)	(122,434)
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares	(59,368)	(52,841)	(51,370)
Dividends paid – preference shares	(36,756)	(30,088)	(22,381)
RenaissanceRe common share repurchases	0	0	(188,591)
RenaissanceRe common share issuance	0	250,000	0
Issuance of preference shares, net of expenses	0	241,448	0
Issuance of debt, net of expenses	396,411	0	295,866
Repayment of debt	0	0	(250,000)
Net third-party redeemable noncontrolling interest share transactions	827,083	665,683	260,475
Taxes paid on withholding shares	(7,253)	(7,862)	(15,139)
Net cash provided by financing activities	1,120,117	1,066,340	28,860
Effect of exchange rate changes on foreign currency cash	2,478	(5,098)	8,222
Net increase (decrease) in cash and cash equivalents	271,146	(253,670)	940,435
Cash and cash equivalents, beginning of year	1,107,922	1,361,592	421,157
Cash and cash equivalents, end of year	1,379,068	1,107,922	1,361,592
RenaissanceRe Holdings Ltd. (Parent Guarantor)
Cash flows (used in) provided by operating activities
Net cash provided by operating activities	(2,861)	17,187	21,118
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	306,579	384,818	261,601
Purchases of fixed maturity investments trading	(66,740)	(520,935)	(344,463)
Net sales (purchases) of short term investments	(116,499)	48,600	243,571
Dividends and return of capital from subsidiaries	1,400,944	672,098	478,496
Net cash used in investing activities	(267,247)	(428,966)	263,952
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares	(59,368)	(52,841)	(51,370)
Dividends paid – preference shares	(36,756)	(30,088)	(22,381)
RenaissanceRe common share repurchases	0	0	(188,591)
RenaissanceRe common share issuance	0	250,000	0
Issuance of preference shares, net of expenses	0	241,448	0
Issuance of debt, net of expenses	396,411	0	0
Repayment of debt			0
Taxes paid on withholding shares	(7,253)	(7,862)	(15,139)
Net cash provided by financing activities	293,034	400,657	(277,481)
Cash and cash equivalents, beginning of year	3,534	14,656	7,067
Cash and cash equivalents, end of year	26,460	3,534	14,656
Other RenaissanceRe Holdings Ltd. Subsidiaries And Eliminations (Non-Guarantor Subsidiaries)
Cash flows provided by financing activities
Repayment of debt			0
RenRe North America Holdings Inc. (Subsidiary Issuer)
Cash flows provided by financing activities
Repayment of debt			0
Reportable Legal Entities | RenaissanceRe Holdings Ltd. (Parent Guarantor)
Cash flows (used in) provided by operating activities
Net cash provided by operating activities	(2,861)	17,187	21,118
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	306,579	384,818	261,601
Purchases of fixed maturity investments trading	(66,740)	(520,935)	(344,463)
Net (purchases) sales of equity investments trading	0	0	0
Net sales (purchases) of short term investments	(116,499)	48,600	243,571
Net purchases of other investments	0	0	0
Net purchases of investments in other ventures	0	0
Return of investment from investment in other ventures	0	0	0
Net (purchases) sales of other assets	0	0
Dividends and return of capital from subsidiaries	1,400,944	672,098	478,496
Contributions to subsidiaries	(1,165,607)	(785,785)	(669,672)
Due to (from) subsidiaries	(625,924)	(227,762)	294,419
Net purchase of TMR	0
Net cash used in investing activities	(267,247)	(428,966)	263,952
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares	(59,368)	(52,841)	(51,370)
Dividends paid – preference shares	(36,756)	(30,088)	(22,381)
RenaissanceRe common share repurchases			(188,591)
RenaissanceRe common share issuance		250,000
Issuance of preference shares, net of expenses		241,448
Issuance of debt, net of expenses	396,411		0
Net third-party redeemable noncontrolling interest share transactions	0	0	0
Taxes paid on withholding shares	(7,253)	(7,862)	(15,139)
Net cash provided by financing activities	293,034	400,657	(277,481)
Effect of exchange rate changes on foreign currency cash	0	0	0
Net increase (decrease) in cash and cash equivalents	22,926	(11,122)	7,589
Cash and cash equivalents, beginning of year	3,534	14,656	7,067
Cash and cash equivalents, end of year	26,460	3,534	14,656
Reportable Legal Entities | Other RenaissanceRe Holdings Ltd. Subsidiaries And Eliminations (Non-Guarantor Subsidiaries)
Cash flows (used in) provided by operating activities
Net cash provided by operating activities	1,769,250	1,135,554	1,363,084
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	16,868,826	11,046,968	8,550,179
Purchases of fixed maturity investments trading	(17,741,881)	(11,840,813)	(9,229,732)
Net (purchases) sales of equity investments trading	(4,483)	15,464	32,265
Net sales (purchases) of short term investments	(1,501,264)	(1,485,040)	79,520
Net purchases of other investments	(202,878)	(199,475)	(19,419)
Net purchases of investments in other ventures	(2,717)	(21,473)
Return of investment from investment in other ventures	11,250	8,464	20,000
Net (purchases) sales of other assets	(4,108)	2,500
Dividends and return of capital from subsidiaries	(1,418,794)	(672,098)	(529,537)
Contributions to subsidiaries	1,290,607	867,632	706,211
Due to (from) subsidiaries	625,840	227,838	(293,800)
Net purchase of TMR	(276,206)
Net cash used in investing activities	(2,355,808)	(2,050,033)	(684,313)
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares	0	0	0
Dividends paid – preference shares	0	0	0
RenaissanceRe common share repurchases			0
RenaissanceRe common share issuance		0
Issuance of preference shares, net of expenses		0
Issuance of debt, net of expenses	0		0
Net third-party redeemable noncontrolling interest share transactions	827,083	665,683	260,475
Taxes paid on withholding shares	0	0	0
Net cash provided by financing activities	827,083	665,683	260,475
Effect of exchange rate changes on foreign currency cash	2,478	(5,098)	8,222
Net increase (decrease) in cash and cash equivalents	243,003	(253,894)	947,468
Cash and cash equivalents, beginning of year	1,091,434	1,345,328	397,860
Cash and cash equivalents, end of year	1,334,437	1,091,434	1,345,328
Reportable Legal Entities | RenRe North America Holdings Inc. (Subsidiary Issuer)
Cash flows (used in) provided by operating activities
Net cash provided by operating activities	3,872	6,315	(8,253)
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	77,798	97,272	100,248
Purchases of fixed maturity investments trading	(77,145)	(72,292)	(99,568)
Net (purchases) sales of equity investments trading	(3,358)	(1,308)	(1,752)
Net sales (purchases) of short term investments	739	(404)	114
Net purchases of other investments	0	0	0
Net purchases of investments in other ventures	0	0
Return of investment from investment in other ventures	0	0	0
Net (purchases) sales of other assets	0	0
Dividends and return of capital from subsidiaries	4,350	0	9,175
Contributions to subsidiaries		(16,847)	0
Contributions to subsidiaries	0
Due to (from) subsidiaries	(166)	(9,525)	13
Net purchase of TMR	0
Net cash used in investing activities	2,218	(3,104)	8,230
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares	0	0	0
Dividends paid – preference shares	0	0	0
RenaissanceRe common share repurchases			0
RenaissanceRe common share issuance		0
Issuance of preference shares, net of expenses		0
Issuance of debt, net of expenses	0		0
Net third-party redeemable noncontrolling interest share transactions	0	0	0
Taxes paid on withholding shares	0	0	0
Net cash provided by financing activities	0	0	0
Effect of exchange rate changes on foreign currency cash	0	0	0
Net increase (decrease) in cash and cash equivalents	6,090	3,211	(23)
Cash and cash equivalents, beginning of year	3,350	139	162
Cash and cash equivalents, end of year	9,440	3,350	139
Reportable Legal Entities | Platinum Underwriters Finance, Inc. (Subsidiary Issuer)
Cash flows (used in) provided by operating activities
Net cash provided by operating activities			(2,272)
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading			289,741
Purchases of fixed maturity investments trading			(143,991)
Net (purchases) sales of equity investments trading			85,324
Net sales (purchases) of short term investments			41,299
Net purchases of other investments			0
Return of investment from investment in other ventures			0
Dividends and return of capital from subsidiaries			0
Contributions to subsidiaries			(26,649)
Due to (from) subsidiaries			(123)
Net cash used in investing activities			245,601
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares			0
Dividends paid – preference shares			0
RenaissanceRe common share repurchases			0
Issuance of debt, net of expenses			0
Repayment of debt			(250,000)
Net third-party redeemable noncontrolling interest share transactions			0
Taxes paid on withholding shares			0
Net cash provided by financing activities			(250,000)
Effect of exchange rate changes on foreign currency cash			0
Net increase (decrease) in cash and cash equivalents			(6,671)
Cash and cash equivalents, beginning of year		0	6,671
Cash and cash equivalents, end of year			0
Reportable Legal Entities | RenaissanceRe Finance, Inc. (Subsidiary Issuer)
Cash flows (used in) provided by operating activities
Net cash provided by operating activities	366,934	62,645	(347,890)
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	60,737	56,518	288,900
Purchases of fixed maturity investments trading	(33,577)	(55,932)	(275,778)
Net (purchases) sales of equity investments trading	0	0	0
Net sales (purchases) of short term investments	(283,717)	455	(493)
Net purchases of other investments	0	0	0
Net purchases of investments in other ventures	0	0
Return of investment from investment in other ventures	0	0	0
Net (purchases) sales of other assets	0	0
Dividends and return of capital from subsidiaries	13,500	0	41,866
Contributions to subsidiaries	(125,000)	(65,000)	(9,890)
Due to (from) subsidiaries	250	9,449	(509)
Net purchase of TMR	0
Net cash used in investing activities	(367,807)	(54,510)	44,096
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares	0	0	0
Dividends paid – preference shares	0	0	0
RenaissanceRe common share repurchases			0
RenaissanceRe common share issuance		0
Issuance of preference shares, net of expenses		0
Issuance of debt, net of expenses	0		295,866
Repayment of debt			0
Net third-party redeemable noncontrolling interest share transactions	0	0	0
Taxes paid on withholding shares	0	0	0
Net cash provided by financing activities	0	0	295,866
Effect of exchange rate changes on foreign currency cash	0	0	0
Net increase (decrease) in cash and cash equivalents	(873)	8,135	(7,928)
Cash and cash equivalents, beginning of year	9,604	1,469	9,397
Cash and cash equivalents, end of year	$ 8,731	$ 9,604	$ 1,469

Subsequent Events (Details)

Subsequent Events (Details)	Jan. 10, 2020USD ($)series	Jan. 01, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 30, 2019USD ($)	Dec. 31, 2018USD ($)
Upsilon RFO Re Ltd. | Primary Beneficiary | Investor | Non-voting preference shares
Subsequent Event [Line Items]
Investment in variable interest entity				$ 618,700,000	$ 512,800,000	$ 856,700,000
Upsilon RFO Re Ltd. | Primary Beneficiary | RenaissanceRe Holdings Ltd.
Subsequent Event [Line Items]
Variable interest entity, ownership percentage				16.50%		14.00%
Upsilon RFO Re Ltd. | Primary Beneficiary | RenaissanceRe Holdings Ltd. | Non-voting preference shares
Subsequent Event [Line Items]
Investment in variable interest entity				$ 100,000,000		$ 109,800,000
Subsequent Event | Upsilon RFO Re Ltd. | Primary Beneficiary | Investor | Non-voting preference shares
Subsequent Event [Line Items]
Investment in variable interest entity		$ 620,900,000
Subsequent Event | Upsilon RFO Re Ltd. | Primary Beneficiary | RenaissanceRe Holdings Ltd.
Subsequent Event [Line Items]
Variable interest entity, ownership percentage		16.50%
Subsequent Event | Upsilon RFO Re Ltd. | Primary Beneficiary | RenaissanceRe Holdings Ltd. | Non-voting preference shares
Subsequent Event [Line Items]
Investment in variable interest entity		$ 103,100,000
Subsequent Event | Mona Lisa Re | Not Primary Beneficiary
Subsequent Event [Line Items]
Number of series of notes | series	2
Face amount	$ 400,000,000
Other liabilities | Upsilon RFO Re Ltd. | Primary Beneficiary | Investor | Non-voting preference shares
Subsequent Event [Line Items]
Investment in variable interest entity			$ 462,800,000

Schedule I. Summary of Invest_2

Schedule I. Summary of Investments Other Than Investments in Related Parties (Details) $ in Thousands	Dec. 31, 2019USD ($)
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Fair Value	$ 17,368,789
Amount at which shown in the Balance Sheet	17,368,789
U.S. treasuries
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	4,439,533
Fair Value	4,467,345
Amount at which shown in the Balance Sheet	4,467,345
Agencies
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	342,162
Fair Value	343,031
Amount at which shown in the Balance Sheet	343,031
Non-U.S. government
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	495,465
Fair Value	497,392
Amount at which shown in the Balance Sheet	497,392
Non-U.S. government-backed corporate
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	321,303
Fair Value	321,356
Amount at which shown in the Balance Sheet	321,356
Corporate
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	3,010,615
Fair Value	3,075,660
Amount at which shown in the Balance Sheet	3,075,660
Agency mortgage-backed
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	1,130,746
Fair Value	1,148,499
Amount at which shown in the Balance Sheet	1,148,499
Non-agency mortgage-backed
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	282,267
Fair Value	294,604
Amount at which shown in the Balance Sheet	294,604
Commercial mortgage-backed
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	489,352
Fair Value	468,698
Amount at which shown in the Balance Sheet	468,698
Asset-backed
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	555,971
Fair Value	555,070
Amount at which shown in the Balance Sheet	555,070
Fixed maturity investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Amortized Cost or Cost	11,067,414
Fair Value	11,171,655
Amount at which shown in the Balance Sheet	11,171,655
Short term investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Fair Value	4,566,277
Amount at which shown in the Balance Sheet	4,566,277
Equity investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Fair Value	436,931
Amount at which shown in the Balance Sheet	436,931
Other investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Fair Value	1,087,377
Amount at which shown in the Balance Sheet	1,087,377
Investments in other ventures, under equity method
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Fair Value	106,549
Amount at which shown in the Balance Sheet	$ 106,549

Schedule II. Condensed Financ_2

Schedule II. Condensed Financial Information Of Registrant (Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets
Fixed maturity investments	$ 11,171,655	$ 8,088,870
Cash and cash equivalents	1,379,068	1,107,922
Investments in subsidiaries	0	0
Accrued investment income	72,461	51,311
Receivable for investments sold	78,369	256,416
Other assets	346,216	135,127
Goodwill and other intangible assets	262,226	237,418
Total assets	26,330,094	18,676,196
Liabilities
Due to subsidiaries	0	0
Other liabilities	932,024	513,609
Total liabilities	17,287,419	11,579,416
Shareholders’ Equity
Preference shares: $1.00 par value – 16,010,000 shares issued and outstanding at December 31, 2019 (2018 – 16,010,000)	650,000	650,000
Common shares: $1.00 par value – 44,148,116 shares issued and outstanding at December 31, 2019 (2018 – 42,207,390)	44,148	42,207
Additional paid-in capital	568,277	296,099
Accumulated other comprehensive loss	(1,939)	(1,433)
Retained earnings	4,710,881	4,058,207
Total shareholders’ equity attributable to RenaissanceRe	5,971,367	5,045,080	$ 4,391,375
Total liabilities, noncontrolling interests and shareholders’ equity	26,330,094	18,676,196
Parent Company
Assets
Fixed maturity investments	1,005	240,443
Short term investments, at fair value (Notes 4 and 5)	189,446	72,917
Cash and cash equivalents	26,460	3,534
Investments in subsidiaries	5,204,260	4,414,475
Due from subsidiaries	10,725	57,039
Accrued investment income	0	1,046
Receivable for investments sold	173	203
Other assets	847,406	458,842
Goodwill and other intangible assets	116,212	120,476
Total assets	6,395,687	5,368,975
Liabilities
Notes and bank loans payable	391,475	300,000
Due to subsidiaries	6,708	6,453
Other liabilities	26,137	17,442
Total liabilities	424,320	323,895
Shareholders’ Equity
Preference shares: $1.00 par value – 16,010,000 shares issued and outstanding at December 31, 2019 (2018 – 16,010,000)	650,000	650,000
Common shares: $1.00 par value – 44,148,116 shares issued and outstanding at December 31, 2019 (2018 – 42,207,390)	44,148	42,207
Additional paid-in capital	568,277	296,099
Accumulated other comprehensive loss	(1,939)	(1,433)
Retained earnings	4,710,881	4,058,207
Total shareholders’ equity attributable to RenaissanceRe	5,971,367	5,045,080
Total liabilities, noncontrolling interests and shareholders’ equity	$ 6,395,687	$ 5,368,975

Schedule II. Condensed Financ_3

Schedule II. Condensed Financial Information Of Registrant (Balance Sheets Parenthetical) (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Fixed maturity investments trading, amortized cost	$ 11,067,414	$ 8,163,962
Preference shares, par value (in usd per share)	$ 1	$ 1
Preference shares, shares issued (in shares)	16,010,000	16,010,000
Preference shares, shares outstanding (in shares)	16,010,000	16,010,000
Common shares, par value (in usd per share)	$ 1	$ 1
Common shares, shares issued (in shares)	44,148,116	42,207,390
Common shares, shares outstanding (in shares)	44,148,116	42,207,390
Parent Company
Condensed Financial Statements, Captions [Line Items]
Fixed maturity investments trading, amortized cost	$ 998	$ 238,989
Preference shares, par value (in usd per share)	$ 1	$ 1
Preference shares, shares issued (in shares)	16,010,000	16,010,000
Preference shares, shares outstanding (in shares)	16,010,000	16,010,000
Common shares, par value (in usd per share)	$ 1	$ 1
Common shares, shares issued (in shares)	44,148,116	42,207,390
Common shares, shares outstanding (in shares)	44,148,116	42,207,390

Schedule II. Condensed Financ_4

Schedule II. Condensed Financial Information Of Registrant (Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues
Net investment income	$ 112,695	$ 113,844	$ 115,832	$ 81,462	$ 53,338	$ 80,696	$ 71,356	$ 56,476	$ 423,833	$ 261,866	$ 222,209
Net foreign exchange gains (losses)	(1,126)	(8,275)	9,309	(2,846)	(932)	(4,566)	(10,687)	3,757	(2,938)	(12,428)	10,628
Net realized and unrealized gains (losses) on investments	17,897	31,938	194,003	170,645	(88,654)	13,630	(17,901)	(82,144)	414,483	(175,069)	135,822
Total revenues	1,105,305	1,051,148	1,238,380	807,121	547,997	629,754	479,204	417,986	4,201,954	2,074,941	2,103,679
Expenses
Interest expense	15,496	15,580	15,534	11,754	11,765	11,769	11,768	11,767	58,364	47,069	44,193
Operational expenses	64,571	53,415	59,814	44,933	58,859	40,593	37,543	41,272	222,733	178,267	160,778
Corporate expenses	17,642	13,844	23,847	38,789	12,108	6,841	8,301	6,733	94,122	33,983	18,572
Total expenses	1,068,420	939,540	780,050	446,462	680,835	579,474	222,831	329,186	3,234,472	1,812,326	2,431,863
Loss before equity in net income (loss) of subsidiaries									967,482	262,615	(328,184)
Equity in net income (loss) of subsidiaries									0	0	0
Net income (loss) attributable to RenaissanceRe	42,962	45,887	377,043	282,906	(74,717)	42,389	197,384	62,308	748,798	227,364	(222,389)
Dividends on preference shares	(9,189)	(9,189)	(9,189)	(9,189)	(9,189)	(9,708)	(5,596)	(5,595)	(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders	$ 33,773	$ 36,698	$ 367,854	$ 273,717	$ (83,906)	$ 32,681	$ 191,788	$ 56,713	712,042	197,276	(244,770)
Parent Company
Revenues
Net investment income									39,629	24,791	23,109
Net foreign exchange gains (losses)									7,342	(3)	(1)
Net realized and unrealized gains (losses) on investments									12,393	633	(1,357)
Total revenues									59,364	25,421	21,751
Expenses
Interest expense									18,086	5,683	1,572
Operational expenses									7,506	7,679	11,314
Corporate expenses									58,393	25,190	18,546
Total expenses									83,985	38,552	31,432
Loss before equity in net income (loss) of subsidiaries									(24,621)	(13,131)	(9,681)
Equity in net income (loss) of subsidiaries									773,419	240,495	(212,708)
Net income (loss) attributable to RenaissanceRe									748,798	227,364	(222,389)
Dividends on preference shares									(36,756)	(30,088)	(22,381)
Net income (loss) available (attributable) to RenaissanceRe common shareholders									$ 712,042	$ 197,276	$ (244,770)

Schedule II. Condensed Financ_5

Schedule II. Condensed Financial Information Of Registrant (Statements of Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ 42,962	$ 45,887	$ 377,043	$ 282,906	$ (74,717)	$ 42,389	$ 197,384	$ 62,308	$ 748,798	$ 227,364	$ (222,389)
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)	0	0
Comprehensive income (loss) attributable to RenaissanceRe									748,292	225,707	(223,298)
Parent Company
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									748,798	227,364	(222,389)
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)	0		$ 0
Comprehensive income (loss) attributable to RenaissanceRe									$ 748,292	$ 225,707	$ (223,298)

Schedule II. Condensed Financ_6

Schedule II. Condensed Financial Information Of Registrant (Statements of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows (used in) provided by operating activities
Net income (loss) attributable to RenaissanceRe	$ 42,962	$ 45,887	$ 377,043	$ 282,906	$ (74,717)	$ 42,389	$ 197,384	$ 62,308	$ 748,798	$ 227,364	$ (222,389)
Less: equity in net (income) loss of subsidiaries									0	0	0
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Net realized and unrealized (gains) losses on investments	(17,897)	$ (31,938)	$ (194,003)	(170,645)	88,654	$ (13,630)	$ 17,901	82,144	(414,483)	175,069	(135,822)
Other									251,351	(223,280)	518,100
Net cash provided by operating activities									2,137,195	1,221,701	1,025,787
Cash flows used in investing activities
Proceeds from maturities and sales of fixed maturity investments trading									17,313,940	11,585,576	9,490,669
Purchases of fixed maturity investments trading									(17,919,343)	(12,489,972)	(10,093,532)
Net sales (purchases) of short term investments									(1,900,741)	(1,436,389)	364,011
Dividends and return of capital from subsidiaries									0	0	0
Net cash used in investing activities									(2,988,644)	(2,536,613)	(122,434)
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares									(59,368)	(52,841)	(51,370)
Dividends paid – preference shares									(36,756)	(30,088)	(22,381)
Issuance of debt, net of expenses									396,411	0	295,866
RenaissanceRe common share repurchases									0	0	(188,591)
RenaissanceRe common share issuance									0	250,000	0
Issuance of preference shares, net of expenses									0	241,448	0
Taxes paid on withholding shares									(7,253)	(7,862)	(15,139)
Net cash provided by financing activities									1,120,117	1,066,340	28,860
Cash and cash equivalents, beginning of year				1,107,922				1,361,592	1,107,922	1,361,592	421,157
Cash and cash equivalents, end of year	1,379,068				1,107,922				1,379,068	1,107,922	1,361,592
Parent Company
Cash flows (used in) provided by operating activities
Net income (loss) attributable to RenaissanceRe									748,798	227,364	(222,389)
Less: equity in net (income) loss of subsidiaries									(773,419)	(240,495)	212,708
Loss before equity in net income of subsidiaries									(24,621)	(13,131)	(9,681)
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Net realized and unrealized (gains) losses on investments									(12,393)	(633)	1,357
Other									34,153	30,951	29,442
Net cash provided by operating activities									(2,861)	17,187	21,118
Cash flows used in investing activities
Proceeds from maturities and sales of fixed maturity investments trading									306,579	384,818	261,601
Purchases of fixed maturity investments trading									(66,740)	(520,935)	(344,463)
Net sales (purchases) of short term investments									(116,499)	48,600	243,571
Dividends and return of capital from subsidiaries									1,400,944	672,098	478,496
Contributions to subsidiaries									(1,165,607)	(785,785)	(669,672)
Due to (from) subsidiary									(625,924)	(227,762)	294,419
Net cash used in investing activities									(267,247)	(428,966)	263,952
Cash flows provided by financing activities
Dividends paid – RenaissanceRe common shares									(59,368)	(52,841)	(51,370)
Dividends paid – preference shares									(36,756)	(30,088)	(22,381)
Issuance of debt, net of expenses									396,411	0	0
RenaissanceRe common share repurchases									0	0	(188,591)
RenaissanceRe common share issuance									0	250,000	0
Issuance of preference shares, net of expenses									0	241,448	0
Taxes paid on withholding shares									(7,253)	(7,862)	(15,139)
Net cash provided by financing activities									293,034	400,657	(277,481)
Net (decrease) increase in cash and cash equivalents									22,926	(11,122)	7,589
Cash and cash equivalents, beginning of year				$ 3,534				$ 14,656	3,534	14,656	7,067
Cash and cash equivalents, end of year	$ 26,460				$ 3,534				$ 26,460	$ 3,534	$ 14,656

Schedule III. Supplementary I_2

Schedule III. Supplementary Insurance Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Deferred Policy Acquisition Costs	$ 663,991	$ 476,661	$ 426,551
Future Policy Benefits, Losses, Claims and Loss Expenses	9,384,349	6,076,271	5,080,408
Unearned Premiums	2,530,975	1,716,021	1,477,609
Premium Revenue	3,338,403	1,976,129	1,717,575
Net Investment Income	423,833	261,866	222,209
Benefits, Claims, Losses and Settlement Expenses	2,097,021	1,120,018	1,861,428
Amortization of Deferred Policy Acquisition Costs	762,232	432,989	346,892
Other Operating Expenses	222,733	178,267	160,778
Net Written Premiums	3,381,493	2,131,902	1,871,325
Property
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Deferred Policy Acquisition Costs	79,795	66,656	63,583
Future Policy Benefits, Losses, Claims and Loss Expenses	4,073,850	3,086,254	2,486,390
Unearned Premiums	539,183	379,943	347,032
Premium Revenue	1,627,494	1,050,831	931,070
Net Investment Income	0	0	0
Benefits, Claims, Losses and Settlement Expenses	965,424	497,895	1,297,985
Amortization of Deferred Policy Acquisition Costs	313,761	177,912	113,816
Other Operating Expenses	139,015	112,954	94,194
Net Written Premiums	1,654,259	1,055,188	978,014
Casualty and Specialty
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Deferred Policy Acquisition Costs	584,196	410,005	362,968
Future Policy Benefits, Losses, Claims and Loss Expenses	5,310,059	2,985,393	2,575,492
Unearned Premiums	1,991,792	1,336,078	1,130,577
Premium Revenue	1,710,909	925,298	786,501
Net Investment Income	0	0	0
Benefits, Claims, Losses and Settlement Expenses	1,131,637	622,320	565,026
Amortization of Deferred Policy Acquisition Costs	448,678	255,079	233,077
Other Operating Expenses	84,546	64,883	66,548
Net Written Premiums	1,727,234	1,076,714	893,307
Other
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
Deferred Policy Acquisition Costs	0	0	0
Future Policy Benefits, Losses, Claims and Loss Expenses	440	4,624	18,526
Unearned Premiums	0	0	0
Premium Revenue	0	0	4
Net Investment Income	423,833	261,866	222,209
Benefits, Claims, Losses and Settlement Expenses	(40)	(197)	(1,583)
Amortization of Deferred Policy Acquisition Costs	(207)	(2)	(1)
Other Operating Expenses	(828)	430	36
Net Written Premiums	$ 0	$ 0	$ 4

Schedule IV. Supplemental Sch_2

Schedule IV. Supplemental Schedule of Reinsurance Premiums (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]
Gross Amounts									$ 404,525	$ 292,219	$ 244,285
Ceded to Other Companies									1,414,383	1,095,886	833,929
Assumed									4,348,261	2,779,796	2,307,219
Net premiums earned (Note 7)	$ 970,125	$ 906,748	$ 911,502	$ 550,028	$ 574,613	$ 531,849	$ 429,385	$ 440,282	$ 3,338,403	$ 1,976,129	$ 1,717,575
Percentage of Amount Assumed to Net									130.00%	141.00%	134.00%

Schedule VI. Supplementary In_2

Schedule VI. Supplementary Insurance Information Concerning Property-Casualty Insurance Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Line Items]
Current year	$ 2,123,876	$ 1,390,767	$ 1,902,424
Prior years	(26,855)	(270,749)	(40,996)
Consolidated Subsidiaries
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Line Items]
Deferred Policy Acquisition Costs	663,991	476,661	426,551
Reserves for Unpaid Claims and Claim Adjustment Expenses	9,384,349	6,076,271	5,080,408
Discount, if any, Deducted	0	0	0
Unearned Premiums	2,530,975	1,716,021	1,477,609
Earned Premiums	3,338,403	1,976,129	1,717,575
Net Investment Income	423,833	261,866	222,209
Current year	2,123,876	1,390,767	1,902,424
Prior years		(270,749)	(40,996)
Amortization of Deferred Policy Acquisition Costs	762,232	432,989	346,892
Paid Claims and Claim Adjustment Expenses	1,098,054	894,769	974,825
Net Premiums Written	$ 3,381,493	$ 2,131,902	$ 1,871,325

Uncategorized Items - rnr10-k20

Label	Element	Value
Equity Method Investments [Member]
Intangible Assets, Net (Including Goodwill)	us-gaap_IntangibleAssetsNetIncludingGoodwill	$ 24,924,000
Intangible Assets, Net (Excluding Goodwill)	us-gaap_IntangibleAssetsNetExcludingGoodwill	14,326,000
Excluding Equity Method Investments [Member]
Intangible Assets, Net (Including Goodwill)	us-gaap_IntangibleAssetsNetIncludingGoodwill	262,226,000
Intangible Assets, Net (Excluding Goodwill)	us-gaap_IntangibleAssetsNetExcludingGoodwill	$ 51,542,000