SUMMARY OF ACCOUNTING POLICIES (Details Narrative)				3 Months Ended		12 Months Ended
	Jan. 01, 2019 USD ($)	Mar. 01, 2018 USD ($)	Feb. 01, 2018 USD ($) shares	Mar. 31, 2019 USD ($) shares	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) joint_venture	Apr. 01, 2017	Mar. 24, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Contracts receivable, factored amount						$ 20,500,000
Contracts receivable, factoring expense						440,000
Contracts receivable, factoring receivable				$ 17,800,000
Deferred financing costs, net of accumulated amortization				1,200,000		1,400,000
Goodwill				424,308,000		418,093,000
Goodwill, impairment loss						3,800,000
Indefinite-lived intangible assets				9,900,000
Impairment of intangible assets						3,900,000
Indefinite-lived trade names						100,000
Income tax expense				$ 1,230,000	$ 2,497,000
Effective tax rate				39.00%	22.40%
Total credit facilities outstanding				$ 0
Investment at cost				31,738,000		30,030,000
Aggregate cost				68,980,000		$ 65,031,000
Number of unconsolidated joint ventures | joint_venture						14
Loss on economic interest transaction				(134,000)
Management service fees				$ 2,100,000	$ 3,400,000
Minimum
Property, Plant and Equipment [Line Items]
Share-based payment award, award vesting period				3 years
Share-based payment award, expiration period				5 years
Maximum
Property, Plant and Equipment [Line Items]
Share-based payment award, award vesting period				5 years
Share-based payment award, expiration period				10 years
Medic Vision
Property, Plant and Equipment [Line Items]
Ownership percentage		14.21%						12.50%
Investment at cost		$ 200,000						$ 1,000,000
Option to purchase additional equity method investment								$ 1,400,000
Additional equity interest acquired		1.96%
Initial qwnership percentage after dilution		12.25%
Aggregate cost				$ 1,200,000
Turner Imaging
Property, Plant and Equipment [Line Items]
Number of shares purchased (in shares) | shares			2,100,000.0
Number of shares purchased, value			$ 2,000,000
Restated Plan
Property, Plant and Equipment [Line Items]
Shares authorized (in shares) | shares				14,000,000
Restated Plan | Minimum
Property, Plant and Equipment [Line Items]
Share-based payment award, award vesting period				3 years
Share-based payment award, expiration period				5 years
Restated Plan | Maximum
Property, Plant and Equipment [Line Items]
Share-based payment award, award vesting period				5 years
Share-based payment award, expiration period				10 years
2016 Caps
Property, Plant and Equipment [Line Items]
Premium liability for 2016 Caps				$ 5,300,000
2016 Caps | September 2020
Property, Plant and Equipment [Line Items]
Notional amounts				150,000,000
2016 Caps | October 2020
Property, Plant and Equipment [Line Items]
Notional amounts				$ 350,000,000
Property and equipment, net | Minimum
Property, Plant and Equipment [Line Items]
PPE estimated useful lives				P3Y
Property and equipment, net | Maximum
Property, Plant and Equipment [Line Items]
PPE estimated useful lives				P15Y
Leasehold Improvements | Minimum
Property, Plant and Equipment [Line Items]
PPE estimated useful lives				P3Y
Leasehold Improvements | Maximum
Property, Plant and Equipment [Line Items]
PPE estimated useful lives				15
2016 Caps | London Interbank Offered Rate (LIBOR)
Property, Plant and Equipment [Line Items]
Basis spread on variable rate				2.00%
Revolving Credit Facility
Property, Plant and Equipment [Line Items]
Deferred financing costs, net of accumulated amortization				$ 1,200,000
Total credit facilities outstanding				41,000,000		$ 28,000,000
RadNet | Santa Monica Imaging Group
Property, Plant and Equipment [Line Items]
Ownership percentage	35.00%						40.00%
Loss on economic interest transaction	$ 2,000
Cedars Sinai Medical Center | Santa Monica Imaging Group
Property, Plant and Equipment [Line Items]
Ownership percentage							60.00%
Additional equity interest acquired	5.00%
Investment owned, value	$ 134,000
Dignity Health | Glendale Advanced Imaging | Joint Venture | Minimum
Property, Plant and Equipment [Line Items]
Variable interest entity, ownership percentage						25.00%
Dignity Health | Glendale Advanced Imaging | Joint Venture | Maximum
Property, Plant and Equipment [Line Items]
Variable interest entity, ownership percentage						55.00%
Promissory Note
Property, Plant and Equipment [Line Items]
Convertible promissory note				$ 100,000		$ 199,000
Promissory Note | Turner Imaging
Property, Plant and Equipment [Line Items]
Convertible promissory note	$ 143,000