SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details - Key Financial Data on Joint Ventures) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance Sheet Data:
Current assets	$ 270,424	$ 241,174
Current liabilities	(398,114)	(327,428)
Total net assets	61,644	60,375
Book value of RadNet joint venture interests	28,079	28,001
Cost in excess of book value of acquired joint venture interests accounted for as equity method goodwill	6,449	6,469
Total value of RadNet joint venture interests	34,528	34,470	$ 37,973
Net revenue	1,071,840	1,154,179	975,146
Net (loss) income	(1,749)	23,440	38,133
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Balance Sheet Data:
Current assets	27,085	27,427
Noncurrent assets	68,686	61,037
Current liabilities	(12,545)	(9,217)
Noncurrent liabilities	(21,582)	(18,872)
Net revenue	101,921	108,051	155,820
Net (loss) income	$ 16,850	$ 18,624	$ 24,596