Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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2. SIGNIFICANT ACCOUNTING POLICIES (Details - Goodwill) - USD ($) $ in Thousands	3 Months Ended	8 Months Ended	9 Months Ended
	Apr. 01, 2018	Sep. 01, 2018	Sep. 30, 2018
Goodwill, beginning balance	$ 256,776	$ 256,776	$ 256,776
Goodwill disposed through the transfer			(80)
Goodwill transferred to assets held for sale			(1,059)
Goodwill, ending balance			274,361
Imaging Services Company of New York, LLC [Member]
Goodwill acquired through acquisitions			2,692
MemorialCare Medical Foundation [Member]
Goodwill acquired through acquisitions			10,158
Adjustments to preliminary allocations of purchase price			$ (3,313)
Womens Imaging Specialists [Member]
Goodwill acquired through acquisitions	4,089
Adjustments to preliminary allocations of purchase price	179
Goodwill, ending balance	4,300
Valley Metabolic Imaging LLC [Member]
Goodwill acquired through acquisitions	1,469
Goodwill, ending balance	1,500
Sierra Imaging Associates LLC [Member]
Goodwill acquired through acquisitions	1,147
Goodwill, ending balance	$ 1,100
Washington Heights Medical Management [Member]
Goodwill acquired through acquisitions		2,303
Goodwill, ending balance		$ 2,300