Basis of preparation and consolidation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Balance sheet
Assets	$ 10,515,812				$ 10,112,564				$ 10,515,812	$ 10,112,564
Liabilities	5,610,461				5,615,913				5,610,461	5,615,913
Redeemable noncontrolling interest	1,111,714				617,791				1,111,714	617,791
Total shareholders' equity available to Validus	3,638,975				3,586,586				3,638,975	3,586,586	$ 3,704,094
Noncontrolling interest	154,662				292,274				154,662	292,274	375,026
Total shareholders' equity	3,793,637				3,878,860				3,793,637	3,878,860	4,079,120
Total liabilities, noncontrolling interests and shareholders’ equity	10,515,812				10,112,564				10,515,812	10,112,564
Statement of comprehensive income
Total revenues									2,345,277	2,102,675	2,143,833
Total expenses									1,864,683	1,543,337	1,548,844
Net income	95,038	$ 92,879	$ 88,351	$ 191,589	146,492	$ 55,342	$ 171,216	$ 181,793	467,857	554,843	595,148
Net (income) attributable to noncontrolling interest	(25,996)	(26,229)	(22,561)	(18,178)	(20,584)	(15,670)	(17,849)	(20,777)	(92,964)	(74,880)	(62,482)
Net income available to Validus	$ 69,042	$ 66,650	$ 65,790	$ 173,411	$ 125,908	$ 39,672	$ 153,367	$ 161,016	374,893	479,963	532,666
Comprehensive income available to Validus									$ 370,880	$ 472,024	$ 530,712
Basic earnings per share available to common shareholders	$ 0.84	$ 0.79	$ 0.77	$ 2.07	$ 1.44	$ 0.42	$ 1.67	$ 1.71	$ 4.47	$ 5.24	$ 5.02
Earnings per diluted share available to common shareholders	$ 0.81	$ 0.78	$ 0.75	$ 1.98	$ 1.38	$ 0.41	$ 1.61	$ 1.65	$ 4.34	$ 5.07	$ 4.94
Statement of cash flows
Net cash provided by operating activities									$ 334,506	$ 340,161	$ 235,366
Net cash (used in) provided by investing activities									(370,834)	(162,681)	253,813
Net cash provided by (used in) financing activities									226,641	(331,102)	(864,048)
Effect of foreign currency rate changes on cash and cash equivalents									(17,605)	(25,310)	(6,364)
Net increase (decrease) in cash									172,708	(178,932)	(381,233)
Cash and cash equivalents - beginning of year				$ 550,401				$ 729,333	550,401	729,333	1,110,566
Cash and cash equivalents - end of year	$ 723,109				$ 550,401				723,109	550,401	729,333
Adjustments for New Accounting Principle, Early Adoption
New Accounting Pronouncement, Early Adoption [Line Items]
Cumulative effect of change on retained earnings	$ 405								405
Adjustments for New Accounting Principle, Early Adoption | As previously reported
Balance sheet
Assets					10,311,621					10,311,621
Liabilities					6,185,112					6,185,112
Redeemable noncontrolling interest					79,956					79,956
Total shareholders' equity available to Validus					3,587,958					3,587,958
Noncontrolling interest					458,595					458,595
Total shareholders' equity					4,046,553					4,046,553
Total liabilities, noncontrolling interests and shareholders’ equity					10,311,621					10,311,621
Statement of comprehensive income
Total revenues										2,085,122	2,158,532
Total expenses										1,547,420	1,561,314
Net income										445,871	542,361
Net (income) attributable to noncontrolling interest										35,464	(9,695)
Net income available to Validus										481,335	532,666
Comprehensive income available to Validus										$ 473,396	$ 530,712
Basic earnings per share available to common shareholders										$ 5.26	$ 5.02
Earnings per diluted share available to common shareholders										$ 5.08	$ 4.94
Statement of cash flows
Net cash provided by operating activities										$ 241,781	$ 265,274
Net cash (used in) provided by investing activities										121,582	(321,436)
Net cash provided by (used in) financing activities										(489,507)	(264,048)
Effect of foreign currency rate changes on cash and cash equivalents										(30,764)	(6,364)
Net increase (decrease) in cash										(156,908)	(326,574)
Cash and cash equivalents - beginning of year				577,240				734,148	577,240	734,148	1,060,722
Cash and cash equivalents - end of year					577,240					577,240	734,148
Adjustments for New Accounting Principle, Early Adoption | Adjustment for adoption of new consolidation guidance
Balance sheet
Assets					(199,057)					(199,057)
Liabilities					(569,199)					(569,199)
Redeemable noncontrolling interest					537,835					537,835
Total shareholders' equity available to Validus					(1,372)					(1,372)
Noncontrolling interest					(166,321)					(166,321)
Total shareholders' equity					(167,693)					(167,693)
Total liabilities, noncontrolling interests and shareholders’ equity					(199,057)					(199,057)
Statement of comprehensive income
Total revenues										17,553	(14,699)
Total expenses										(4,083)	(12,470)
Net income										108,972	52,787
Net (income) attributable to noncontrolling interest										(110,344)	(52,787)
Net income available to Validus										(1,372)	0
Comprehensive income available to Validus										$ (1,372)	$ 0
Basic earnings per share available to common shareholders										$ (0.02)	$ 0.00
Earnings per diluted share available to common shareholders										$ (0.01)	$ 0.00
Statement of cash flows
Net cash provided by operating activities										$ 98,380	$ (29,908)
Net cash (used in) provided by investing activities										(284,263)	575,249
Net cash provided by (used in) financing activities										158,405	(600,000)
Effect of foreign currency rate changes on cash and cash equivalents										5,454	0
Net increase (decrease) in cash										(22,024)	(54,659)
Cash and cash equivalents - beginning of year				$ (26,839)				$ (4,815)	$ (26,839)	(4,815)	49,844
Cash and cash equivalents - end of year					$ (26,839)					$ (26,839)	$ (4,815)