Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
NET INCOME	$ 532,449	$ 259,847	$ 393,692
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX:
Currency translation adjustments	(46,602)	71,669	(57,920)
Employee benefit plans:
Prior service costs (net of tax benefit of $543 for the year ended December 31, 2018)	(2,653)
Actuarial gain (loss) (net of tax expense (benefit) of $131, $(3,507) and $(5,205) for the years ended December 31, 2018, 2017 and 2016, respectively)	(2,781)	2,085	(24,473)
Adjustment for items reclassified to earnings (net of tax expense of $2,335, $2,220 and $1,757 for the years ended December 31, 2018, 2017 and 2016, respectively)	10,735	7,951	2,526
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	(41,301)	81,705	(79,867)
COMPREHENSIVE INCOME	491,148	341,552	313,825
LESS - COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	5,323	6,265	5,993
COMPREHENSIVE INCOME ATTRIBUTABLE TO LAZARD LTD	$ 485,825	$ 335,287	$ 307,832