XML 107 R89.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Reserve for Claims and Claim Expenses - Schedule of Incurred and Paid Claims Development (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | $ 33,925,137 |  |  |  |  |  |  |  |  |
IBNR and ACR | 11,098,566 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 19,053,753 |  |  |  |  |  |  |  |  |
Outstanding liabilities from accident year 2013 and prior, net of reinsurance | 403,209 |  |  |  |  |  |  |  |  |
Adjustment for unallocated loss adjustment expenses | 90,185 |  |  |  |  |  |  |  |  |
Unamortized fair value adjustments recorded in connection with acquisitions | (222,195) |  |  |  |  |  |  |  |  |
Liability for claims and claim expenses, net of reinsurance | 15,142,583 |  |  |  |  |  |  |  |  |
Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 13,527,160 |  |  |  |  |  |  |  |  |
IBNR and ACR | 3,341,206 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 8,469,660 |  |  |  |  |  |  |  |  |
Outstanding liabilities from accident year 2013 and prior, net of reinsurance | 77,214 |  |  |  |  |  |  |  |  |
Adjustment for unallocated loss adjustment expenses | 13,949 |  |  |  |  |  |  |  |  |
Unamortized fair value adjustments recorded in connection with acquisitions | (51,689) |  |  |  |  |  |  |  |  |
Liability for claims and claim expenses, net of reinsurance | 5,096,974 |  |  |  |  |  |  |  |  |
Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 20,397,977 |  |  |  |  |  |  |  |  |
IBNR and ACR | 7,757,360 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 10,584,093 |  |  |  |  |  |  |  |  |
Outstanding liabilities from accident year 2013 and prior, net of reinsurance | 325,995 |  |  |  |  |  |  |  |  |
Adjustment for unallocated loss adjustment expenses | 76,236 |  |  |  |  |  |  |  |  |
Unamortized fair value adjustments recorded in connection with acquisitions | (170,506) |  |  |  |  |  |  |  |  |
Liability for claims and claim expenses, net of reinsurance | 10,045,609 |  |  |  |  |  |  |  |  |
Accident Year 2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,168,571 | $ 1,180,232 | $ 1,189,016 | $ 1,199,667 | $ 1,229,153 | $ 1,216,176 | $ 1,231,639 | $ 1,261,814 | $ 1,292,051 | $ 1,349,682
IBNR and ACR | 37,966 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,090,421 | 1,085,206 | 1,067,201 | 1,037,804 | 1,008,653 | 953,310 | 886,043 | 800,559 | 651,426 | 351,514
Accident Year 2014 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 315,158 | 317,076 | 319,529 | 325,325 | 331,347 | 331,610 | 326,513 | 331,455 | 352,583 | 380,622
IBNR and ACR | 1,284 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 313,571 | 311,424 | 311,708 | 308,420 | 308,616 | 301,017 | 292,484 | 276,964 | 229,525 | 125,296
Accident Year 2014 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 853,413 | 863,156 | 869,487 | 874,342 | 897,806 | 884,566 | 905,126 | 930,359 | 939,468 | 969,060
IBNR and ACR | 36,682 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 776,850 | 773,782 | 755,493 | 729,384 | 700,037 | 652,293 | 593,559 | 523,595 | 421,901 | $ 226,218
Accident Year 2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,495,256 | 1,497,021 | 1,504,626 | 1,502,100 | 1,512,704 | 1,534,787 | 1,580,294 | 1,612,942 | 1,682,812 |
IBNR and ACR | 33,929 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,425,849 | 1,399,216 | 1,361,819 | 1,311,496 | 1,246,427 | 1,144,296 | 1,015,747 | 792,149 | 458,736 |
Accident Year 2015 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 376,792 | 377,861 | 375,769 | 384,744 | 389,650 | 399,498 | 416,585 | 459,762 | 511,360 |
IBNR and ACR | 3,095 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 373,247 | 369,281 | 366,340 | 363,600 | 359,414 | 348,033 | 324,960 | 279,692 | 142,694 |
Accident Year 2015 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,118,464 | 1,119,160 | 1,128,857 | 1,117,356 | 1,123,054 | 1,135,289 | 1,163,709 | 1,153,180 | 1,171,452 |
IBNR and ACR | 30,834 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,052,602 | 1,029,935 | 995,479 | 947,896 | 887,013 | 796,263 | 690,787 | 512,457 | $ 316,042 |
Accident Year 2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,782,676 | 1,804,992 | 1,770,150 | 1,755,166 | 1,837,107 | 1,870,041 | 1,907,527 | 1,897,875 |  |
IBNR and ACR | 18,118 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,633,339 | 1,603,460 | 1,537,961 | 1,432,356 | 1,296,066 | 1,118,420 | 907,567 | 473,090 |  |
Accident Year 2016 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 530,843 | 541,396 | 522,330 | 526,318 | 554,287 | 576,902 | 607,340 | 588,366 |  |
IBNR and ACR | 3,114 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 487,678 | 491,344 | 486,482 | 475,616 | 449,190 | 415,348 | 332,918 | 146,671 |  |
Accident Year 2016 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,251,833 | 1,263,596 | 1,247,820 | 1,228,848 | 1,282,820 | 1,293,139 | 1,300,187 | 1,309,509 |  |
IBNR and ACR | 15,004 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,145,661 | 1,112,116 | 1,051,479 | 956,740 | 846,876 | 703,072 | 574,649 | $ 326,419 |  |
Accident Year 2017 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 3,180,295 | 3,190,159 | 3,255,713 | 3,285,056 | 3,357,851 | 3,443,204 | 3,697,137 |  |  |
IBNR and ACR | 201,303 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 2,745,342 | 2,600,250 | 2,436,312 | 2,248,481 | 1,878,698 | 1,513,515 | 973,719 |  |  |
Accident Year 2017 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,532,082 | 1,559,925 | 1,624,156 | 1,681,670 | 1,698,844 | 1,824,613 | 2,018,855 |  |  |
IBNR and ACR | 127,946 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,323,458 | 1,300,750 | 1,252,995 | 1,232,669 | 1,123,051 | 939,895 | 663,451 |  |  |
Accident Year 2017 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,648,213 | 1,630,234 | 1,631,557 | 1,603,386 | 1,659,007 | 1,618,591 | 1,678,282 |  |  |
IBNR and ACR | 73,357 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,421,884 | 1,299,500 | 1,183,317 | 1,015,812 | 755,647 | 573,620 | $ 310,268 |  |  |
Accident Year 2018 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 3,112,753 | 3,081,439 | 3,075,000 | 3,205,113 | 3,266,784 | 3,030,203 |  |  |  |
IBNR and ACR | 406,074 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 2,374,401 | 2,252,816 | 2,029,342 | 1,719,662 | 1,300,839 | 676,031 |  |  |  |
Accident Year 2018 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,216,792 | 1,267,732 | 1,280,066 | 1,408,253 | 1,465,633 | 1,374,423 |  |  |  |
IBNR and ACR | 171,088 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 971,282 | 1,032,771 | 990,041 | 954,175 | 776,630 | 454,838 |  |  |  |
Accident Year 2018 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,895,961 | 1,813,707 | 1,794,934 | 1,796,860 | 1,801,151 | 1,655,780 |  |  |  |
IBNR and ACR | 234,986 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,403,119 | 1,220,045 | 1,039,301 | 765,487 | 524,209 | $ 221,193 |  |  |  |
Accident Year 2019 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 2,613,203 | 2,600,638 | 2,669,111 | 2,754,429 | 2,765,868 |  |  |  |  |
IBNR and ACR | 355,502 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 2,042,749 | 1,723,144 | 1,390,797 | 1,019,032 | 386,711 |  |  |  |  |
Accident Year 2019 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 953,986 | 1,017,085 | 1,103,449 | 1,191,214 | 1,203,828 |  |  |  |  |
IBNR and ACR | 123,856 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 813,107 | 748,804 | 660,693 | 475,613 | 165,811 |  |  |  |  |
Accident Year 2019 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,659,217 | 1,583,553 | 1,565,662 | 1,563,215 | 1,562,040 |  |  |  |  |
IBNR and ACR | 231,646 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,229,642 | 974,340 | 730,104 | 543,419 | $ 220,900 |  |  |  |  |
Accident Year 2020 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 4,408,976 | 4,423,413 | 4,429,197 | 4,435,130 |  |  |  |  |  |
IBNR and ACR | 1,079,825 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 2,788,153 | 2,296,810 | 1,773,193 | 761,877 |  |  |  |  |  |
Accident Year 2020 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 2,036,200 | 2,092,021 | 2,098,289 | 1,989,861 |  |  |  |  |  |
IBNR and ACR | 428,120 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,317,414 | 1,109,201 | 836,501 | 283,840 |  |  |  |  |  |
Accident Year 2020 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 2,372,776 | 2,331,392 | 2,330,908 | 2,445,269 |  |  |  |  |  |
IBNR and ACR | 651,705 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,470,739 | 1,187,609 | 936,692 | $ 478,037 |  |  |  |  |  |
Accident Year 2021 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 5,178,965 | 5,378,071 | 5,552,945 |  |  |  |  |  |  |
IBNR and ACR | 1,413,339 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 2,966,887 | 2,116,223 | 892,239 |  |  |  |  |  |  |
Accident Year 2021 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 2,628,136 | 2,713,942 | 2,744,649 |  |  |  |  |  |  |
IBNR and ACR | 301,855 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,862,525 | 1,366,213 | 580,026 |  |  |  |  |  |  |
Accident Year 2021 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 2,550,829 | 2,664,129 | 2,808,296 |  |  |  |  |  |  |
IBNR and ACR | 1,111,484 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,104,362 | 750,010 | $ 312,213 |  |  |  |  |  |  |
Accident Year 2022 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 5,680,547 | 5,966,078 |  |  |  |  |  |  |  |
IBNR and ACR | 3,271,322 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 1,463,927 | 285,530 |  |  |  |  |  |  |  |
Accident Year 2022 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 2,463,435 | 2,584,543 |  |  |  |  |  |  |  |
IBNR and ACR | 1,134,057 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 772,239 | 79,480 |  |  |  |  |  |  |  |
Accident Year 2022 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 3,217,112 | 3,381,535 |  |  |  |  |  |  |  |
IBNR and ACR | 2,137,265 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 691,688 | $ 206,050 |  |  |  |  |  |  |  |
Accident Year 2023 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 5,303,895 |  |  |  |  |  |  |  |  |
IBNR and ACR | 4,281,188 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 522,685 |  |  |  |  |  |  |  |  |
Accident Year 2023 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 1,473,736 |  |  |  |  |  |  |  |  |
IBNR and ACR | 1,046,791 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | 235,139 |  |  |  |  |  |  |  |  |
Accident Year 2023 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Claim Expenses, Net of Reinsurance | 3,830,159 |  |  |  |  |  |  |  |  |
IBNR and ACR | 3,234,397 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Claim Expenses, Net of Reinsurance | $ 287,546 |  |  |  |  |  |  |  |  |

X
- Definition Short-duration Insurance Contracts, Liability for Unpaid Claims and Claim Adjustment Expense, Unamortized Fair Value Adjustments Associated With Acquisition + References No definition available. + Details
Name: | rnr_ShortdurationInsuranceContractsLiabilityforUnpaidClaimsandClaimAdjustmentExpenseUnamortizedFairValueAdjustmentsAssociatedWithAcquisition
Namespace Prefix: | rnr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ClaimsDevelopmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after reinsurance, of paid claims and allocated claim adjustment expense used in claims development for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (b) -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4B + Details
Name: | us-gaap_ShortdurationInsuranceContractsCumulativePaidClaimsAndAllocatedClaimAdjustmentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Undiscounted amount, after reinsurance, of incurred-but-not-reported (IBNR) liabilities plus expected development on reported claims, for claims and allocated claim adjustment expense for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4D -Subparagraph (a) -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4D Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4E -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4E + Details
Name: | us-gaap_ShortdurationInsuranceContractsIncurredButNotReportedIbnrClaimsLiabilityNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Undiscounted amount, after reinsurance, of incurred claims and allocated claim adjustment expense used in claims development for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (a) -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4B + Details
Name: | us-gaap_ShortdurationInsuranceContractsIncurredClaimsAndAllocatedClaimAdjustmentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Undiscounted amount, after reinsurance, of the liability for unpaid claims and allocated claim adjustment expense for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4B -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4B Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4C -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4C + Details
Name: | us-gaap_ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Undiscounted amount, after reinsurance, of the liability for unpaid claims and allocated claim adjustment expense for short-duration insurance contracts for accident years not separately presented in claim development information. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4B -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4B + Details
Name: | us-gaap_ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNetNotSeparatelyPresented
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of liability for unallocated claim adjustment expense for short-duration insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4C -SubTopic 40 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-4C + Details
Name: | us-gaap_ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAccumulatedUnallocatedClaimAdjustmentExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=rnr_PropertySegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=rnr_CasualtyandSpecialtySegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2014Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2015Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2016Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractsAccidentYear2017Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractsAccidentYear2018Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractAccidentYear2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractAccidentYear2020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractAccidentYear2021Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractAccidentYear2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractAccidentYear2023Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |