Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
REVENUE
Interest income	$ 1,340	$ 4,013	$ 3,752	$ 7,813
Total revenue	592,264	650,801	1,150,421	1,312,479
Interest expense	19,972	20,111	40,115	38,115
Net revenue	572,292	630,690	1,110,306	1,274,364
OPERATING EXPENSES
Compensation and benefits	351,568	372,470	671,323	744,724
Occupancy and equipment	30,574	30,953	62,772	59,248
Marketing and business development	6,517	28,784	26,703	56,768
Technology and information services	32,629	38,825	63,987	70,880
Professional services	16,728	19,144	31,273	33,361
Fund administration and outsourced services	24,053	28,493	50,443	57,423
Amortization and other acquisition-related costs	455	5,042	901	8,512
Other	13,903	5,294	22,942	22,100
Total operating expenses	476,427	529,005	930,344	1,053,016
OPERATING INCOME	95,865	101,685	179,962	221,348
Provision for income taxes	22,789	28,172	48,555	51,359
NET INCOME	73,076	73,513	131,407	169,989
LESS - NET INCOME (LOSS) ATTRIBUTABLE TO NONCONTROLLING INTERESTS	(382)	7,736	(6,073)	7,170
NET INCOME ATTRIBUTABLE TO LAZARD LTD	$ 73,458	$ 65,777	$ 137,480	$ 162,819
WEIGHTED AVERAGE SHARES OF COMMON STOCK OUTSTANDING:
Basic	106,662,064	111,981,204	106,483,013	111,962,729
Diluted	111,487,749	116,175,349	112,803,964	118,497,717
NET INCOME PER SHARE OF COMMON STOCK:
Basic	$ 0.68	$ 0.57	$ 1.27	$ 1.44
Diluted	$ 0.66	$ 0.55	$ 1.22	$ 1.36
Investment Banking and Other Advisory Fees [Member]
REVENUE
Revenue	$ 304,259	$ 328,974	$ 601,928	$ 664,778
Asset Management Fees [Member]
REVENUE
Revenue	245,291	296,581	514,509	589,019
Other [Member]
REVENUE
Revenue	$ 41,374	$ 21,233	$ 30,232	$ 50,869