Document And Entity Information - shares	9 Months Ended
	Mar. 31, 2016	Sep. 15, 2016
Document Information [Line Items]
Document Type	10-Q/A
Amendment Flag	true
Document Period End Date	Mar. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q3
Entity Registrant Name	AUTHENTIDATE HOLDING CORP
Entity Central Index Key	0000885074
Current Fiscal Year End Date	--06-30
Entity Filer Category	Smaller Reporting Company
Trading Symbol	ADAT
Entity Common Stock, Shares Outstanding		5,772,258
Amendment Description	Authentidate Holding Corp. (the “Company”) is filing this Amendment No. 1 to its Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2016 previously filed with the Securities and Exchange Commission on September 27, 2016 (the “Original Form 10-Q”) to amend and restate in their entirety the following items in the Original Form 10-Q: (i) the unaudited interim financial statements as of and for the fiscal quarter ended March 31, 2016 set forth in Item 1 of Part 1; (ii) the “Management's Discussion and Analysis of Financial Condition and Results of Operation” set forth in Item 2 of Part 1, and (iii) the discussion involving the Company’s disclosure controls and internal control over financial reporting, set forth in Item 4 of Part 1. We have also updated the signature page, the certifications of our Chief Executive Officer and our financial statements formatted in Extensible Business Reporting Language (XBRL). The restatement and the other aforementioned matters are described in Note 2 to the unaudited consolidated financial statements included in this Amendment No. 1 on Form 10-Q/A (the “Amended Form 10-Q”). As described in more detail in Note 2 to the unaudited consolidated financial statements included in this Amended Form 10-Q, the restatement of the unaudited interim financial statements included in the Original Form 10-Q corrects an error in the Company’s accounting for changes in reimbursement rates and payment adjudication processes which resulted in an overstatement of revenues and accounts receivable balances for the three and nine-month periods ended March 31, 2016. In addition, certain adjustments to correct the provision for income taxes and certain immaterial grammatical and formatting changes were made to this Amended Form 10-Q. The information in the Original Form 10-Q is amended to read in its entirety as set forth in this Amended Form 10-Q. Except to reflect the restatement of the interim financial statements and other matters specifically identified as amended or restated in the first paragraph of this Explanatory Note, the information in the Original Form 10-Q and this Amended Form 10-Q has not been updated or otherwise changed to reflect any events, conditions or other developments that have occurred or existed since September 27, 2016, the date the Original Form 10-Q was filed with the SEC. Accordingly, except solely with regard to the restatement and the other matters specifically identified as amended or restated in the first paragraph of this Explanatory Note, all information in this Amended Form 10-Q speaks only as of September 27, 2016. References made in this Amended Form 10-Q to “this Form 10-Q” or similar statements, means this Amendment on Form 10-Q/A unless the context requires otherwise. For more information about the restatement, please see the Company’s Current Report on Form 8-K filed on February 22, 2017.