Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 434,063us-gaap_ProfitLoss	$ 165,114us-gaap_ProfitLoss	$ 92,785us-gaap_ProfitLoss
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX:
Currency translation adjustments	(49,971)	(15,536)	15,686
Amortization of interest rate hedge		2,502	1,055
Employee benefit plans:
Actuarial loss (net of tax benefit of $9,045, $6,388 and $12,950 for the years ended December 31, 2014, 2013 and 2012, respectively)	(21,983)	(13,500)	(40,298)
Adjustment for items reclassified to earnings (net of tax expense of $1,923, $1,929 and $1,145 for the years ended December 31, 2014, 2013 and 2012, respectively)	4,749	4,605	4,399
OTHER COMPREHENSIVE LOSS, NET OF TAX	(67,205)	(21,929)	(19,158)
COMPREHENSIVE INCOME	366,858	143,185	73,627
LESS - COMPREHENSIVE INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	6,785	4,769	8,315
COMPREHENSIVE INCOME ATTRIBUTABLE TO LAZARD LTD	$ 360,073us-gaap_ComprehensiveIncomeNetOfTax	$ 138,416us-gaap_ComprehensiveIncomeNetOfTax	$ 65,312us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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