Document and Entity Information (USD $)	12 Months Ended
Dec. 31, 2012	Mar. 08, 2013	Jun. 29, 2012
Document And Entity Information
Entity Registrant Name	RadNet, Inc.
Entity Central Index Key	0000790526
Document Type	10-K
Document Period End Date	Dec. 31, 2012
Amendment Flag	true
Amendment Description	We are filing this Form 10-K/A (Amendment No. 1) to our Annual Report on Form 10-K for the fiscal year ended December 31, 2012, originally filed with the U.S. Securities and Exchange Commission on March 18, 2013 (the "Original Filing"), solely for the purpose of complying with Rule 3-09 of Regulation S-X. Rule 3-09 requires that we file financial statements of certain unconsolidated joint ventures in which we hold equity interests of 50% or less and account for them under the equity method to the extent that the unconsolidated joint ventures are individually significant. Under Rule 3-09 of Regulation S-X, we are permitted to file combined financial statements for individually significant unconsolidated joint ventures which are in the same line of business. We have determined that as of and for the year ended December 31, 2012, four of our unconsolidated joint venture interests including Franklin Imaging Joint Venture, Carroll County Radiology, LLC, MRI at St. Joseph Medical Center, LLC and Greater Baltimore Diagnostic Imaging Partnership, (collectively, the “Group”), were significant unconsolidated joint ventures under Rule 3-09. Accordingly, we are filing in this Amendment No. 1 to include the combined financial statements of the Group under Item 8 – Financial Statements and Supplementary Data, and we are amending Item 15 - Exhibits and Financial Statement Schedules, to include a list of the financial statements and exhibits being filed herewith. We are also filing updated Certificates of our Chief Executive Officer and Chief Financial Officer under Sections 302 and 906 of the Sarbanes Oxley Act of 2002. Except as described above, no other changes have been made to the Original Filing, and this Form 10-K/A does not amend, update or change any other items or disclosures in the Original Filing. This Form 10-K/A does not reflect events occurring after the Original Filing. Accordingly, this Amendment should be read in conjunction with the Original Filing and our other filings with the SEC subsequent to the Original Filing
Current Fiscal Year End Date	--12-31
Is Entity a Well-known Seasoned Issuer?	No
Is Entity a Voluntary Filer?	No
Is Entity's Reporting Status Current?	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 81,917,304
Entity Common Stock, Shares Outstanding		38,990,482
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2012

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