SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details - Earnings Per Share) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Net income attributable to RadNet, Inc. common stockholders	$ 29,136	$ 5,039	$ 5,406	$ (7,338)	$ (7,276)	$ 3,229	$ 5,310	$ (1,210)	$ 32,243	$ 53	$ 7,230
BASIC NET INCOME PER SHARE ATTRIBUTABLE TO RADNET, INC. COMMON STOCKHOLDERS
Weighted average number of common shares outstanding during the period (in shares)	48,633	48,011	47,969	47,823	47,237	46,954	46,756	46,560	48,114,275	46,880,775	46,244,188
Basic net income per share attributable to RadNet, inc. common stockholders (in dollars per share)	$ 0.60	$ 0.10	$ 0.11	$ (0.15)	$ (0.15)	$ 0.07	$ 0.11	$ (0.03)	$ 0.67	$ 0.00	$ 0.16
DILUTED NET INCOME PER SHARE ATTRIBUTABLE TO RADNET, INC. COMMON STOCKHOLDERS
Weighted average number of common shares outstanding during the period (in shares)	48,633	48,011	47,969	47,823	47,237	46,954	46,756	46,560	48,114,275	46,880,775	46,244,188
Add nonvested restricted stock subject only to service vesting (in shares)									180,631	274,940	220,416
Add additional shares issuable upon exercise of stock options and warrants (in shares)									384,093	246,206	190,428
Weighted average number of common shares used in calculating diluted net income per share (in shares)	49,259	48,615	48,526	47,823	47,886	47,578	47,196	46,560	48,678,999	47,401,921	46,655,032
Diluted net income per share attributable to RadNet, Inc. common stockholders (in dollars per share)	$ 0.59	$ 0.10	$ 0.11	$ (0.15)	$ (0.15)	$ 0.07	$ 0.11	$ (0.03)	$ 0.66	$ 0.00	$ 0.15
Stock options excluded from the computation of diluted per share amounts:
Weighted average shares for which the exercise price exceeds average market price of common stock (in shares)									6,250	175,037	245,313