Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Mar. 22, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	true
Amendment Description	Iconix Brand Group, Inc. (the “Company”) is filing this Amendment No. 1 on Form 10-K/A (the “Amended Filing”) to correct an error in the Supplemental Disclosure of Cash Flow Information for the year ended December 31, 2015 contained in the Company’s Consolidated Statements of Cash Flows. Additionally, the Company corrected two typographical errors in Footnote 1 to the Company’s Notes to Consolidated Financial Statements under the captions “Concentration of Credit Risk” and “Accounts Receivable.” Except as described above, no other amendments are being made to the Annual Report on Form 10-K. This Form 10-K/A does not reflect events occurring after the filing of the Company’s Annual Report on Form 10-K or modify or update the disclosures contained in the Annual Report on Form 10-K in any way other than as set forth above.
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Trading Symbol	ICON
Entity Registrant Name	ICONIX BRAND GROUP, INC.
Entity Central Index Key	0000857737
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		48,537,725
Entity Public Float			$ 1,204.6