SIGNIFICANT ACCOUNTING POLICIES (Details - Goodwill) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 418,093
Goodwill transferred to assets held for sale	(123)
Goodwill, ending balance	424,308
Medical Arts Radiological Group, PC
Goodwill [Roll Forward]
Goodwill, purchase accounting adjustments	722
Dignity Health
Goodwill [Roll Forward]
Goodwill acquired through acquisitions	1
West Valley Imaging Group, LLC
Goodwill [Roll Forward]
Goodwill acquired through acquisitions	2,490
Hudson Valley Radiology Associates
Goodwill [Roll Forward]
Goodwill acquired through acquisitions	$ 3,125

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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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of divestiture 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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