13. QUARTERLY RESULTS OF OPERATIONS (Details-Statements of Operations) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Results Of Operations Details-statements Of Operations
Net service fee revenue	$ 215,706	$ 208,366	$ 204,289	$ 181,267	$ 185,552	$ 184,059	$ 179,082	$ 168,876	$ 809,628	$ 717,569	$ 702,986
Total operating expenses	205,256	191,137	190,905	183,213	170,676	168,824	163,436	161,328	770,511	664,264	659,383
Total other expenses	10,109	5,731	10,836	6,723	9,951	10,401	10,803	25,468	56,623	43,911
Equity in earnings of joint ventures	(2,626)	(1,992)	(3,207)	(1,102)	(2,248)	(2,009)	(1,646)	(1,067)	(8,927)	(6,970)	(6,194)
Benefit from (provision for) income taxes	(1,707)	(5,199)	(2,192)	3,091	(2,878)	(2,334)	(1,233)	4,478	(6,007)	(1,967)	(3,510)
Net (loss) income	1,260	8,291	3,563	(4,476)	4,295	4,509	5,256	(12,375)	8,638	1,685	2,376
Net income attributable to noncontrolling intersts	379	304	168	78	90	58	112	49	929	309	256
Net (loss) income attributable to Radnet, Inc. common stockholders	$ 881	$ 7,987	$ 3,395	$ (4,554)	$ 4,205	$ 4,451	$ 5,144	$ (12,424)	$ 7,709	$ 1,376	$ 2,120
Basic net (loss) income attributable to Radnet, Inc. common stockholders (loss) earnings per share:	$ .02	$ .18	$ .08	$ (.11)	$ 0.10	$ 0.11	$ 0.13	$ (0.31)	$ 0.18	$ 0.03	$ .05
Diluted net (loss) income attributable to Radnet, Inc. common stockholders (loss) earnings per share:	$ .02	$ .18	$ .08	$ (.11)	$ 0.10	$ 0.10	$ 0.13	$ (0.31)	$ .17	$ 0.03	$ .05
Weighted average shares outstanding - Basic	45,454,000	43,637,000	43,370,000	42,747,000	41,783,000	41,645,000	40,817,000	40,010,000	43,805,794	41,070,077	39,140,480
Weighted average shares outstanding - Diluted	46,545,000	44,752,000	44,686,000	42,747,000	44,182,000	44,034,000	43,263,000	40,010,000	45,171,372	43,149,196	39,814,535