Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows (used in) provided by operating activities
Net income	$ 92,207	$ 132,274
Adjustments to reconcile net income to net cash (used in) provided by operating activities
Amortization, accretion and depreciation	13,740	6,390
Equity in undistributed earnings (losses) of other ventures	(314)	4,818
Net realized and unrealized losses (gains) on investments	82,144	(43,373)
Net unrealized (gains) losses included in net investment income	(1,465)	(6,863)
Change in:
Premiums receivable	(380,008)	(295,952)
Prepaid reinsurance premiums	(261,375)	(186,831)
Reinsurance recoverable	14,309	(46,255)
Deferred acquisition costs	(50,459)	(53,356)
Reserve for claims and claim expenses	(167,681)	86,394
Unearned premiums	484,137	364,922
Reinsurance balances payable	769,858	298,283
Other	(632,442)	(59,412)
Net cash (used in) provided by operating activities	(37,349)	201,039
Cash flows used in investing activities
Proceeds from sales and maturities of fixed maturity investments trading	2,318,859	2,682,386
Purchases of fixed maturity investments trading	(2,312,461)	(3,007,124)
Net sales of equity investments trading	137	13,747
Net (purchases) sales of short term investments	(594,641)	245,693
Net (purchases) sales of other investments	(98,639)	36,402
Net purchases of investments in other ventures	(17,974)	0
Return of investment from investment in other ventures	0	20,000
Net cash used in investing activities	(704,719)	(8,896)
Cash flows provided by (used in) financing activities
Dividends paid – RenaissanceRe common shares	(13,224)	(13,027)
Dividends paid – preference shares	(5,595)	(5,595)
RenaissanceRe common share repurchases	0	(80,009)
Net third party redeemable noncontrolling interest share transactions	52,759	(51,166)
Taxes paid on withholding shares	(7,034)	(11,018)
Net cash provided by (used in) financing activities	26,906	(160,815)
Effect of exchange rate changes on foreign currency cash	1,543	1,602
Net (decrease) increase in cash and cash equivalents	(713,619)	32,930
Cash and cash equivalents, beginning of period	1,361,592	421,157
Cash and cash equivalents, end of period	$ 647,973	$ 454,087