SIGNIFICANT ACCOUNTING POLICIES (Details - Revenue) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue from External Customer [Line Items]
Total revenue	$ 292,692	$ 242,148	$ 853,338	$ 717,935
Commercial insurance
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	163,152	135,445	475,064	397,193
Medicare
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	61,599	48,243	175,825	141,348
Medicaid
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	7,128	6,323	21,564	19,129
Workers' compensation/personal injury
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	10,865	8,810	32,950	25,714
Other patient revenue
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	6,085	6,205	17,947	18,318
Management fee revenue
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	1,792	3,615	5,662	11,237
Teleradiology and Software revenue
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	4,412	4,063	12,861	11,879
Other
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	6,875	4,848	20,878	16,318
Service fee revenue
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	261,908	217,552	762,751	641,136
Revenue under capitation arrangements
Revenue from External Customer [Line Items]
Service fee revenue, net of contractual allowances and discounts	$ 30,784	$ 24,596	$ 90,587	$ 76,799