Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands		Total	Common Stock [Member]		Additional Paid-In-Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), Net of Tax [Member]	Class A Common Stock Held By Subsidiaries [Member]	Total Lazard Ltd Stockholders' Equity [Member]	Noncontrolling Interests [Member]	Series A Preferred Stock [Member]
Balance at Dec. 31, 2012		$ 651,540	$ 1,282		$ 846,050	$ 182,647	$ (110,541)	$ (349,782)	$ 569,656	$ 81,884
Balance (in shares) at Dec. 31, 2012			128,216,424	[1]				12,802,938			7,921
Comprehensive income (loss):
NET INCOME		165,114				160,212			160,212	4,902
Other comprehensive loss - net of tax		(21,929)					(21,796)		(21,796)	(133)
Amortization of share-based incentive compensation		235,898			234,608				234,608	1,290
Dividend-equivalents		(290)			16,927	(17,215)			(288)	(2)
Class A common stock dividends		(121,620)				(121,620)			(121,620)
Purchase of Class A common stock		(132,477)						$ (132,477)	(132,477)
Purchase of Class A common stock (in shares)								3,488,101
Delivery of Class A common stock in connection with shared-based incentive compensation and related tax benefit		(132,493)			(357,858)	(609)		$ 225,974	(132,493)
Delivery of Class A common stock in connection with shared-based incentive compensation and related tax benefit (in shares)								(7,745,699)
Class A common stock issued in exchange for Lazard Group common membership interests			$ 9		(9)
Class A common stock issued in exchange for Lazard Group common membership interests (in shares)	[1]		839,658
Business acquisitions and related equity transactions:
Class A common stock issuable (including related amortization)		790			786				786	4
Delivery of Class A common stock					(6,893)	(179)		$ 7,072
Delivery of Class A common stock (in shares)								(228,275)
Distributions to noncontrolling interests, net		(13,535)								(13,535)
Adjustments related to noncontrolling interests		(1,000)			4,288		(667)		3,621	(4,621)
Balance at Dec. 31, 2013		629,998	$ 1,291		737,899	203,236	(133,004)	$ (249,213)	560,209	69,789
Balance (in shares) at Dec. 31, 2013			129,056,082	[1]				8,317,065			7,921
Comprehensive income (loss):
NET INCOME		434,063				427,277			427,277	6,786
Other comprehensive loss - net of tax		(67,205)					(67,204)		(67,204)	(1)
Amortization of share-based incentive compensation		206,195			206,195				206,195
Dividend-equivalents		(2,081)			17,536	(19,617)			(2,081)
Class A common stock dividends		(146,241)				(146,241)			(146,241)
Purchase of Class A common stock		(192,657)						$ (192,657)	(192,657)
Purchase of Class A common stock (in shares)								4,114,206
Delivery of Class A common stock in connection with shared-based incentive compensation and related tax benefit		(80,659)			(258,798)			$ 178,139	(80,659)
Delivery of Class A common stock in connection with shared-based incentive compensation and related tax benefit (in shares)								(4,923,252)
Class A common stock issued in exchange for Lazard Group common membership interests			$ 7		(7)
Class A common stock issued in exchange for Lazard Group common membership interests (in shares)	[1]		710,009
Business acquisitions and related equity transactions:
Class A common stock issuable (including related amortization)		570			570				570
Delivery of Class A common stock					(2,488)			$ 2,488
Delivery of Class A common stock (in shares)								(57,274)
Distributions to noncontrolling interests, net		(11,926)								(11,926)
Adjustments related to noncontrolling interests					1,893		(558)		1,335	(1,335)
Balance at Dec. 31, 2014		770,057	$ 1,298		702,800	464,655	(200,766)	$ (261,243)	706,744	63,313
Balance (in shares) at Dec. 31, 2014			129,766,091	[1]				7,450,745			7,921
Comprehensive income (loss):
NET INCOME		992,932				986,373			986,373	6,559
Other comprehensive loss - net of tax		(33,590)					(33,590)		(33,590)
Amortization of share-based incentive compensation		226,723			226,723				226,723
Dividend-equivalents		(2,361)			34,255	(36,616)			(2,361)
Class A common stock dividends		(290,684)				(290,684)			(290,684)
Purchase of Class A common stock		(172,772)						$ (172,772)	(172,772)
Purchase of Class A common stock (in shares)								3,438,789
Delivery of Class A common stock in connection with shared-based incentive compensation and related tax benefit		(106,978)			(362,417)			$ 255,439	(106,978)
Delivery of Class A common stock in connection with shared-based incentive compensation and related tax benefit (in shares)								(6,608,837)
Business acquisitions and related equity transactions:
Delivery of Class A common stock					(1,327)			$ 1,327
Delivery of Class A common stock (in shares)								(27,316)
Distributions to noncontrolling interests, net		(16,021)								(16,021)
Balance at Dec. 31, 2015		$ 1,367,306	$ 1,298		$ 600,034	$ 1,123,728	$ (234,356)	$ (177,249)	$ 1,313,455	$ 53,851
Balance (in shares) at Dec. 31, 2015			129,766,091					4,253,381			7,921

[1] Includes 129,056,081, 129,766,091 and 129,766,091 shares of the Company's Class A common stock issued at December 31, 2013, 2014 and 2015, respectively, and 1 share of the Company's Class B common stock issued at December 31, 2013.