Schedule II. Condensed Financial Information Of Registrant (Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues
Net investment income	$ 47,316	$ 51,423	$ 54,124	$ 28,863	$ 45,918	$ 28,338	$ 38,604	$ 39,707	$ 181,726	$ 152,567	$ 124,316
Net foreign exchange gains (losses)	(5,420)	(5,986)	(690)	(1,692)	1,203	616	(1,740)	(3,130)	(13,788)	(3,051)	6,260
Other income	5,177	2,268	2,654	4,079	8,200	2,306	1,427	1,539	14,178	13,472	(423)
Net realized and unrealized gains (losses) on investments	(49,967)	59,870	69,772	61,653	(42,817)	(41,138)	(26,712)	41,749	141,328	(68,918)	41,433
Total revenues	353,967	442,466	483,284	448,120	377,375	358,240	397,567	381,920	1,727,837	1,515,102	1,260,077
Expenses
Interest expense	10,534	10,536	10,536	10,538	10,550	10,542	9,862	5,316	42,144	36,270	17,402
Operational expenses	49,948	40,493	51,073	56,235	64,300	54,518	54,673	45,621	197,749	219,112	190,639
Operating and corporate expenses	11,888	11,537	5,752	8,225	10,791	7,322	12,868	45,533	37,402	76,514	22,749
Total expenses	270,417	255,721	304,116	267,195	243,053	250,536	308,413	216,724	1,097,449	1,018,726	573,213
Loss before equity in net income of subsidiaries									630,388	496,376	686,864
Equity in net income of subsidiaries									0	0	0
Net income attributable to RenaissanceRe	75,031	152,420	141,921	133,590	97,801	81,124	78,829	173,438	502,962	431,192	532,718
Dividends on preference shares	(5,595)	(5,595)	(5,596)	(5,595)	(5,595)	(5,595)	(5,596)	(5,595)	(22,381)	(22,381)	(22,381)
Net income available to RenaissanceRe common shareholders	$ 69,436	$ 146,825	$ 136,325	$ 127,995	$ 92,206	$ 75,529	$ 73,233	$ 167,843	480,581	408,811	510,337
Parent Company
Revenues
Net investment income									24,178	15,391	2,706
Net foreign exchange gains (losses)									(2)	4	(13)
Other income									(772)	663	0
Net realized and unrealized gains (losses) on investments									4,151	(2,080)	83
Total revenues									27,555	13,978	2,776
Expenses
Interest expense									562	1,255	0
Operational expenses									13,716	4,249	(4,890)
Operating and corporate expenses									26,848	40,808	20,787
Total expenses									41,126	46,312	15,897
Loss before equity in net income of subsidiaries									(13,571)	(32,334)	(13,121)
Equity in net income of subsidiaries									516,533	463,526	545,839
Net income attributable to RenaissanceRe									502,962	431,192	532,718
Dividends on preference shares									(22,381)	(22,381)	(22,381)
Net income available to RenaissanceRe common shareholders									$ 480,581	$ 408,811	$ 510,337