Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
REVENUE
Interest income	$ 13,127	$ 7,144	$ 5,233
Total revenue	2,884,833	2,697,829	2,383,663
Interest expense	58,481	53,518	50,292
Net revenue	2,826,352	2,644,311	2,333,371
OPERATING EXPENSES
Compensation and benefits	1,514,735	1,512,873	1,340,543
Occupancy and equipment	121,107	124,842	109,305
Marketing and business development	108,644	89,205	83,202
Technology and information services	139,693	121,671	97,461
Professional services	61,349	47,932	45,512
Fund administration and outsourced services	132,964	71,305	63,421
Amortization and other acquisition-related (benefits) costs	(15,897)	9,514	35,247
Benefit pursuant to tax receivable agreement	(6,495)	(202,546)
Other	89,486	44,069	41,219
Total operating expenses	2,145,586	1,818,865	1,815,910
OPERATING INCOME	680,766	825,446	517,461
Provision for income taxes	148,317	565,599	123,769
NET INCOME	532,449	259,847	393,692
LESS - NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	5,324	6,264	5,994
NET INCOME ATTRIBUTABLE TO LAZARD LTD	$ 527,125	$ 253,583	$ 387,698
WEIGHTED AVERAGE SHARES OF COMMON STOCK OUTSTANDING:
Basic	119,006,531	121,573,442	124,770,401
Diluted	129,767,592	132,479,728	132,633,630
NET INCOME PER SHARE OF COMMON STOCK:
Basic	$ 4.43	$ 2.09	$ 3.11
Diluted	$ 4.06	$ 1.91	$ 2.92
Investment Banking and Other Advisory Fees [Member]
REVENUE
Revenue	$ 1,554,114	$ 1,385,536	$ 1,298,364
Asset Management Fees [Member]
REVENUE
Revenue	1,268,399	1,195,550	998,887
Other [Member]
REVENUE
Revenue	$ 49,193	$ 109,599	$ 81,179