XML 103 R88.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Reserve for Claims and Claim Expenses (Incurred and Paid Claims Development) (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Dec. 31, 2008 | Dec. 31, 2007
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | $ 7,732,540 |  |  |  |  |  |  |  |  |
IBNR and ACR | 1,641,732 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 5,423,909 |  |  |  |  |  |  |  |  |
Outstanding liabilities from accident year 2006 and prior, net of reinsurance | 226,695 |  |  |  |  |  |  |  |  |
Claims and claim expenses, net of reinsurance, from the Company's former Bermuda-based insurance operations | 2,114 |  |  |  |  |  |  |  |  |
Adjustment for unallocated claim expenses | 20,256 |  |  |  |  |  |  |  |  |
Unamortized fair value adjustments recorded in connection with the acquisition of Platinum | 11,034 |  |  |  |  |  |  |  |  |
Liability for claims and claim expenses, net of reinsurance | 2,568,730 |  |  |  |  |  |  |  |  |
Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 3,600,130 |  |  |  |  |  |  |  |  |
IBNR and ACR | 395,680 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 3,023,772 |  |  |  |  |  |  |  |  |
Outstanding liabilities from accident year 2006 and prior, net of reinsurance | 3,865 |  |  |  |  |  |  |  |  |
Adjustment for unallocated claim expenses | 2,394 |  |  |  |  |  |  |  |  |
Unamortized fair value adjustments recorded in connection with the acquisition of Platinum | 1,419 |  |  |  |  |  |  |  |  |
Liability for claims and claim expenses, net of reinsurance | 584,036 |  |  |  |  |  |  |  |  |
Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 4,132,410 |  |  |  |  |  |  |  |  |
IBNR and ACR | 1,246,052 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 2,400,137 |  |  |  |  |  |  |  |  |
Outstanding liabilities from accident year 2006 and prior, net of reinsurance | 222,830 |  |  |  |  |  |  |  |  |
Adjustment for unallocated claim expenses | 17,862 |  |  |  |  |  |  |  |  |
Unamortized fair value adjustments recorded in connection with the acquisition of Platinum | 9,615 |  |  |  |  |  |  |  |  |
Liability for claims and claim expenses, net of reinsurance | 1,982,580 |  |  |  |  |  |  |  |  |
2007 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 770,219 | $ 774,396 | $ 766,845 | $ 778,185 | $ 806,487 | $ 868,747 | $ 911,337 | $ 958,206 | $ 1,025,247 | $ 1,113,667
IBNR and ACR | 67,726 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 682,644 | 657,017 | 638,348 | 613,200 | 588,997 | 541,511 | 469,657 | 371,280 | 281,119 | 91,877
2007 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 199,383 | 198,666 | 199,792 | 206,168 | 213,228 | 234,120 | 246,823 | 250,975 | 309,228 | 387,866
IBNR and ACR | 397 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 199,893 | 198,654 | 197,735 | 197,533 | 194,327 | 190,603 | 187,998 | 172,512 | 150,938 | 45,530
2007 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 570,836 | 575,730 | 567,053 | 572,017 | 593,259 | 634,627 | 664,514 | 707,231 | 716,019 | 725,801
IBNR and ACR | 67,329 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 482,751 | 458,363 | 440,613 | 415,667 | 394,670 | 350,908 | 281,659 | 198,768 | 130,181 | $ 46,347
2008 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 1,247,506 | 1,262,048 | 1,272,298 | 1,294,396 | 1,317,055 | 1,390,282 | 1,408,748 | 1,429,241 | 1,469,251 |
IBNR and ACR | 48,658 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 1,140,094 | 1,118,434 | 1,090,977 | 1,060,160 | 1,013,041 | 937,678 | 797,242 | 591,482 | 275,968 |
2008 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 684,281 | 683,658 | 691,030 | 700,312 | 715,285 | 748,918 | 752,501 | 752,349 | 851,049 |
IBNR and ACR | 919 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 682,539 | 681,131 | 679,303 | 675,595 | 661,664 | 628,673 | 538,944 | 391,008 | 247,162 |
2008 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 563,225 | 578,390 | 581,268 | 594,084 | 601,770 | 641,364 | 656,247 | 676,892 | 618,202 |
IBNR and ACR | 47,739 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 457,555 | 437,303 | 411,674 | 384,565 | 351,377 | 309,005 | 258,298 | 200,474 | $ 28,806 |
2009 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 522,566 | 527,374 | 536,393 | 557,623 | 582,725 | 622,181 | 639,182 | 704,560 |  |
IBNR and ACR | 30,006 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 462,192 | 455,919 | 434,257 | 395,580 | 363,190 | 319,313 | 267,983 | 96,378 |  |
2009 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 134,359 | 134,059 | 134,722 | 134,013 | 138,131 | 144,352 | 163,124 | 218,607 |  |
IBNR and ACR | 411 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 132,731 | 131,823 | 130,858 | 126,433 | 120,839 | 113,279 | 99,400 | 56,065 |  |
2009 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 388,207 | 393,315 | 401,671 | 423,610 | 444,594 | 477,829 | 476,058 | 485,953 |  |
IBNR and ACR | 29,595 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 329,461 | 324,096 | 303,399 | 269,147 | 242,351 | 206,034 | 168,583 | $ 40,313 |  |
2010 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 863,129 | 854,924 | 864,328 | 867,523 | 898,572 | 946,271 | 988,403 |  |  |
IBNR and ACR | 79,809 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 709,672 | 620,545 | 549,898 | 495,847 | 425,914 | 309,807 | 126,401 |  |  |
2010 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 558,982 | 549,097 | 545,333 | 527,126 | 522,678 | 557,062 | 605,753 |  |  |
IBNR and ACR | 35,715 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 469,028 | 393,497 | 367,495 | 332,275 | 289,918 | 211,124 | 91,585 |  |  |
2010 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 304,147 | 305,827 | 318,995 | 340,397 | 375,894 | 389,209 | 382,650 |  |  |
IBNR and ACR | 44,094 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 240,644 | 227,048 | 182,403 | 163,572 | 135,996 | 98,683 | $ 34,816 |  |  |
2011 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 1,314,451 | 1,349,227 | 1,377,450 | 1,454,063 | 1,533,946 | 1,611,509 |  |  |  |
IBNR and ACR | 113,383 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 1,145,239 | 1,101,596 | 1,013,577 | 861,359 | 522,071 | 249,556 |  |  |  |
2011 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 1,007,368 | 1,036,122 | 1,056,822 | 1,103,441 | 1,153,960 | 1,230,463 |  |  |  |
IBNR and ACR | 48,082 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 921,820 | 896,001 | 838,968 | 716,364 | 409,111 | 201,650 |  |  |  |
2011 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 307,083 | 313,105 | 320,628 | 350,622 | 379,986 | 381,046 |  |  |  |
IBNR and ACR | 65,301 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 223,419 | 205,595 | 174,609 | 144,995 | 112,960 | $ 47,906 |  |  |  |
2012 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 651,764 | 679,446 | 705,316 | 767,534 | 862,333 |  |  |  |  |
IBNR and ACR | 132,561 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 459,269 | 415,911 | 356,102 | 265,612 | 165,581 |  |  |  |  |
2012 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 275,504 | 293,136 | 310,842 | 343,561 | 436,244 |  |  |  |  |
IBNR and ACR | 38,243 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 218,060 | 208,115 | 188,744 | 144,861 | 100,044 |  |  |  |  |
2012 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 376,260 | 386,310 | 394,474 | 423,973 | 426,089 |  |  |  |  |
IBNR and ACR | 94,318 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 241,209 | 207,796 | 167,358 | 120,751 | $ 65,537 |  |  |  |  |
2013 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 465,948 | 504,401 | 552,965 | 614,066 |  |  |  |  |  |
IBNR and ACR | 127,969 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 283,707 | 240,046 | 177,423 | 86,344 |  |  |  |  |  |
2013 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 149,197 | 170,629 | 192,681 | 223,542 |  |  |  |  |  |
IBNR and ACR | 15,879 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 125,744 | 115,043 | 91,436 | 48,550 |  |  |  |  |  |
2013 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 316,751 | 333,772 | 360,284 | 390,524 |  |  |  |  |  |
IBNR and ACR | 112,090 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 157,963 | 125,003 | 85,987 | $ 37,794 |  |  |  |  |  |
2014 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 600,956 | 613,360 | 657,958 |  |  |  |  |  |  |
IBNR and ACR | 155,602 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 268,806 | 199,632 | 110,863 |  |  |  |  |  |  |
2014 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 146,689 | 153,770 | 182,518 |  |  |  |  |  |  |
IBNR and ACR | 14,820 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 118,304 | 95,758 | 55,101 |  |  |  |  |  |  |
2014 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 454,267 | 459,590 | 475,440 |  |  |  |  |  |  |
IBNR and ACR | 140,782 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 150,502 | 103,874 | $ 55,762 |  |  |  |  |  |  |
2015 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 620,623 | 635,553 |  |  |  |  |  |  |  |
IBNR and ACR | 343,935 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 192,864 | 95,712 |  |  |  |  |  |  |  |
2015 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 192,593 | 224,669 |  |  |  |  |  |  |  |
IBNR and ACR | 62,748 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 108,173 | 62,173 |  |  |  |  |  |  |  |
2015 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 428,030 | 410,884 |  |  |  |  |  |  |  |
IBNR and ACR | 281,187 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 84,691 | $ 33,539 |  |  |  |  |  |  |  |
2016 |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 675,378 |  |  |  |  |  |  |  |  |
IBNR and ACR | 542,083 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 79,422 |  |  |  |  |  |  |  |  |
2016 | Property |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 251,774 |  |  |  |  |  |  |  |  |
IBNR and ACR | 178,466 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | 47,480 |  |  |  |  |  |  |  |  |
2016 | Casualty and Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred claims and claim expenses, net of reinsurance | 423,604 |  |  |  |  |  |  |  |  |
IBNR and ACR | 363,617 |  |  |  |  |  |  |  |  |
Cumulative paid claims and claim expenses, net of reinsurance | $ 31,942 |  |  |  |  |  |  |  |  |

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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671311-158438 + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4D -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671317-158438 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4E -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671321-158438 + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671311-158438 + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671311-158438 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671315-158438 + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671311-158438 + Details
Name: | us-gaap_ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNetNotSeparatelyPresented
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of reconciling item for the reconciliation of the liability in the disclosure of claims development (in excess of) less than the liability for unpaid claims and claims adjustment expense for short-duration insurance contracts, classified as other. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671315-158438 + Details
Name: | us-gaap_ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimAdjustmentExpenseOtherReconcilingItem
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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671315-158438 + 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_ShortdurationInsuranceContractsAccidentYear2007Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2008Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2009Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2010Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2011Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2012Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2013Member
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: |