8. SUPPLEMENTAL GUARANTOR INFORMATION (Details 1) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
CURRENT ASSETS
Cash and cash equivalents	$ 431	$ 362	$ 1,834	$ 2,455
Accounts receivable, net	134,939	129,194
Current deferred tax assets	8,792	7,607
Prepaid expenses and other current assets	20,213	18,737
Total current assets	164,375	155,900
PROPERTY AND EQUIPMENT, NET	217,443	216,560
OTHER ASSETS
Goodwill	197,090	193,871
Other intangible assets	52,236	51,674
Deferred financing costs, net	11,387	11,977
Investment in joint ventures	27,959	28,598
Deferred tax assets, net of current portion	53,054	52,790
Deposits and other	3,590	3,749
Total assets	727,134	715,119
LIABILITIES AND STOCKHOLDERS' EQUITY DEFICIT
Accounts payable, accrued expenses and other	112,808	105,929
Due to affiliates	1,495	1,602
Deferred revenue	1,276	1,273
Current portion of deferred rent	1,262	1,164
Current portion of notes payable	5,226	4,703
Current portion of obligations under capital leases	3,138	3,942
Total current liabilities	125,205	118,613
LONG-TERM LIABILITIES
Deferred rent, net of current portion	16,185	15,850
Line of credit	34,500	33,000
Notes payable, net of current portion	537,799	537,009
Obligations under capital lease, net of current portion	3,350	3,753
Other non-current liabilities	8,481	8,895
Total liabilities	725,520	717,120
EQUITY (DEFICIT)
Total RadNet, Inc.'s equity (deficit)	(414)	(2,635)
Noncontrolling interests	2,028	634
Total equity (deficit)	1,614	(2,001)
Total liabilities and stockholders' equity (deficit)	727,134	715,119
Parent [Member]
OTHER ASSETS
Investment in subsidiaries	(414)	(2,635)
Total assets	(414)	(2,635)
EQUITY (DEFICIT)
Total RadNet, Inc.'s equity (deficit)	(414)	(2,635)
Total equity (deficit)	(414)	(2,635)
Total liabilities and stockholders' equity (deficit)	(414)	(2,635)
Subsidiary Issuer [Member]
CURRENT ASSETS
Cash and cash equivalents		362		1,366
Prepaid expenses and other current assets	13,382	9,735
Total current assets	13,382	10,097
PROPERTY AND EQUIPMENT, NET	49,203	48,025
OTHER ASSETS
Goodwill	49,139	48,954
Other intangible assets	160	170
Deferred financing costs, net	11,387	11,977
Investment in subsidiaries	350,608	342,796
Deposits and other	1,596	1,821
Total assets	475,475	463,840
LIABILITIES AND STOCKHOLDERS' EQUITY DEFICIT
Intercompany	(165,623)	(176,217)
Accounts payable, accrued expenses and other	56,129	57,939
Current portion of deferred rent	605	574
Current portion of notes payable	3,500	3,500
Current portion of obligations under capital leases	947	1,186
Total current liabilities	(104,442)	(113,018)
LONG-TERM LIABILITIES
Deferred rent, net of current portion	9,703	9,579
Line of credit	34,500	33,000
Notes payable, net of current portion	535,640	536,248
Obligations under capital lease, net of current portion	488	666
Total liabilities	475,889	466,475
EQUITY (DEFICIT)
Total RadNet, Inc.'s equity (deficit)	(414)	(2,635)
Total equity (deficit)	(414)	(2,635)
Total liabilities and stockholders' equity (deficit)	475,475	463,840
Guarantor Subsidiaries [Member]
CURRENT ASSETS
Cash and cash equivalents	431		881
Accounts receivable, net	64,597	76,838
Current deferred tax assets	8,792	7,607
Prepaid expenses and other current assets	6,097	8,308
Total current assets	79,917	92,753
PROPERTY AND EQUIPMENT, NET	161,970	168,401
OTHER ASSETS
Goodwill	143,211	144,072
Other intangible assets	51,974	51,394
Investment in subsidiaries	14,746	9,217
Investment in joint ventures	27,959	28,598
Deferred tax assets, net of current portion	53,054	52,790
Deposits and other	1,935	1,928
Total assets	534,766	549,153
LIABILITIES AND STOCKHOLDERS' EQUITY DEFICIT
Intercompany	112,383	138,223
Accounts payable, accrued expenses and other	48,361	41,696
Due to affiliates	1,495	1,602
Deferred revenue	1,276	1,273
Current portion of deferred rent	611	590
Current portion of notes payable	1,004	1,203
Current portion of obligations under capital leases	1,301	2,756
Total current liabilities	166,431	187,343
LONG-TERM LIABILITIES
Deferred rent, net of current portion	6,290	6,271
Notes payable, net of current portion	638	761
Obligations under capital lease, net of current portion	2,318	3,087
Other non-current liabilities	8,481	8,895
Total liabilities	184,158	206,357
EQUITY (DEFICIT)
Total RadNet, Inc.'s equity (deficit)	350,608	342,796
Total equity (deficit)	350,608	342,796
Total liabilities and stockholders' equity (deficit)	534,766	549,153
Non-Guarantor Subsidiaries [Member]
CURRENT ASSETS
Cash and cash equivalents			953	1,089
Accounts receivable, net	70,342	52,356
Prepaid expenses and other current assets	734	694
Total current assets	71,076	53,050
PROPERTY AND EQUIPMENT, NET	6,270	134
OTHER ASSETS
Goodwill	4,740	845
Other intangible assets	102	110
Deposits and other	59
Total assets	82,247	54,139
LIABILITIES AND STOCKHOLDERS' EQUITY DEFICIT
Intercompany	53,240	37,994
Accounts payable, accrued expenses and other	8,318	6,294
Current portion of deferred rent	46
Current portion of notes payable	722
Current portion of obligations under capital leases	890
Total current liabilities	63,216	44,288
LONG-TERM LIABILITIES
Deferred rent, net of current portion	192
Notes payable, net of current portion	1,521
Obligations under capital lease, net of current portion	544
Total liabilities	65,473	44,288
EQUITY (DEFICIT)
Total RadNet, Inc.'s equity (deficit)	14,746	9,217
Noncontrolling interests	2,028	634
Total equity (deficit)	16,774	9,851
Total liabilities and stockholders' equity (deficit)	82,247	54,139
Eliminations [Member]
OTHER ASSETS
Investment in subsidiaries	(364,940)	(349,378)
Total assets	(364,940)	(349,378)
EQUITY (DEFICIT)
Total RadNet, Inc.'s equity (deficit)	(364,940)	(349,378)
Total equity (deficit)	(364,940)	(349,378)
Total liabilities and stockholders' equity (deficit)	$ (364,940)	$ (349,378)