Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
REVENUE
Interest income	$ 3,962	$ 3,029	$ 11,775	$ 7,877
Total revenue	611,073	640,800	1,923,552	2,180,533
Interest expense	20,005	14,319	58,120	41,416
Net revenue	591,068	626,481	1,865,432	2,139,117
OPERATING EXPENSES
Compensation and benefits	391,363	343,987	1,136,087	1,165,193
Occupancy and equipment	29,856	28,848	89,104	88,326
Marketing and business development	27,318	21,868	84,086	75,755
Technology and information services	34,076	36,394	104,956	102,173
Professional services	15,105	13,353	48,466	42,498
Fund administration and outsourced services	28,425	34,748	85,848	103,159
Amortization and other acquisition-related (benefits) costs	1,022	(5,851)	9,534	(13,468)
Other	11,530	14,453	33,630	51,032
Total operating expenses	538,695	487,800	1,591,711	1,614,668
OPERATING INCOME	52,373	138,681	273,721	524,449
Provision for income taxes	4,177	29,956	55,536	105,684
NET INCOME	48,196	108,725	218,185	418,765
LESS - NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	1,492	1,651	8,662	5,036
NET INCOME ATTRIBUTABLE TO LAZARD LTD	$ 46,704	$ 107,074	$ 209,523	$ 413,729
WEIGHTED AVERAGE SHARES OF COMMON STOCK OUTSTANDING:
Basic	109,285,727	119,456,516	111,070,395	119,897,626
Diluted	113,881,690	129,859,728	116,959,041	130,750,392
NET INCOME PER SHARE OF COMMON STOCK:
Basic	$ 0.42	$ 0.90	$ 1.87	$ 3.45
Diluted	$ 0.40	$ 0.82	$ 1.77	$ 3.16
Investment Banking and Other Advisory Fees [Member]
REVENUE
Revenue	$ 305,303	$ 309,690	$ 970,081	$ 1,139,860
Asset Management Fees [Member]
REVENUE
Revenue	287,140	312,790	876,159	986,777
Other [Member]
REVENUE
Revenue	$ 14,668	$ 15,291	$ 65,537	$ 46,019