Stockholders' Equity - Changes in Ownership Interests (Detail)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Lazard Ltd [Member]
Change In Ownership Interest [Line Items]
Ending balance (in shares)	129,056,081	128,216,423	123,009,311
Percentage of Ownership, Ending Balance	99.50%	98.80%	94.80%
LAZ-MD Holdings [Member]
Change In Ownership Interest [Line Items]
Ending balance (in shares)	710,009	1,549,667	6,756,779
Percentage of Ownership, Ending Balance	0.50%	1.20%	5.20%
Total Lazard Group Common Membership Interests [Member]
Change In Ownership Interest [Line Items]
Ending balance (in shares)	129,766,090	129,766,090	129,766,090