SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details - Key Financial Data on Joint Ventures) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Balance Sheet Data:
Current assets	$ 28,317	$ 47,813
Noncurrent assets	45,912	107,481
Current liabilities	(4,300)	(16,655)
Noncurrent liabilities	(4,898)	(42,072)
Total net assets	65,031	96,567
Book value of RadNet joint venture interests	30,030	45,935
Cost in excess of book value of acquired joint venture interests accounted for as equity method goodwill	7,943	6,500
Cost in excess of book value of acquired joint venture interests accounted for as equity method goodwill	37,973	52,435	$ 43,509
Total book value of other joint venture partner interests	35,001	50,632
Net revenue	155,820	188,849	160,134
Net income	$ 24,596	$ 28,644	$ 21,933