CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	DeepHealth, Inc.	Total Radnet, Inc.'s Equity	Common Stock	Common Stock DeepHealth, Inc.	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2018				48,977,485
Beginning balance, value at Dec. 31, 2018	$ 200,253		$ 127,184	$ 5		$ 242,835	$ 2,259	$ (117,915)	$ 73,069
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of options (in shares)				10,000
Issuance of common stock upon exercise of options	50		50			50
Issuance of common stock under the equity compensation plan (in shares)				726,042
Issuance of common stock under the equity compensation plan	0
Stock-based compensation expense	6,993		6,993			6,993
Issuance of common stock for acquisition (in shares)				440,207
Issuance of common stock for acquisition	6,000		6,000			6,000
Forfeiture of restricted stock (in shares)				(1,500)
Forfeiture of restricted stock	(5)		(5)			(5)
Sale of noncontrolling interests, net of taxes	5,098		3,090			3,090			2,008
Purchase of noncontrolling interests	(1,818)								(1,818)
Contribution from noncontrolling partner	750								750
Issuance of common stock for purchase of Nulogix (in shares)				101,902
Issuance of common stock for purchase of Nulogix	1,500		1,500			1,500
Change in cumulative foreign currency translation adjustment	(28)		(28)				(28)
Change in fair value of cash flow hedge, net of taxes	(14,481)		(14,481)				(14,481)
Amount of loss reclassified from accumulated OCI into income (prior period effective portion)	0
Net (loss) income	10,760		4,360					4,360	6,400
Ending balance (in shares) at Sep. 30, 2019				50,254,136
Ending balance, value at Sep. 30, 2019	215,072		134,663	$ 5		260,463	(12,250)	(113,555)	80,409
Beginning balance (in shares) at Jun. 30, 2019				50,127,234
Beginning balance, value at Jun. 30, 2019	212,430		133,918	$ 5		257,607	(6,942)	(116,752)	78,512
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under the equity compensation plan (in shares)				25,000
Issuance of common stock under the equity compensation plan	0
Stock-based compensation expense	1,356		1,356			1,356
Issuance of common stock for purchase of membership interest in HVRA (in shares)				101,902
Issuance of common stock for purchase of membership interest in HVRA	1,500		1,500			1,500
Change in cumulative foreign currency translation adjustment	(23)		(23)				(23)
Change in fair value of cash flow hedge, net of taxes	(5,283)		(5,283)				(5,283)
Amount of loss reclassified from accumulated OCI into income (prior period effective portion)	0
Other	0						(2)	2
Net (loss) income	5,092		3,195					3,195	1,897
Ending balance (in shares) at Sep. 30, 2019				50,254,136
Ending balance, value at Sep. 30, 2019	215,072		134,663	$ 5		260,463	(12,250)	(113,555)	80,409
Beginning balance (in shares) at Dec. 31, 2019				50,314,328
Beginning balance, value at Dec. 31, 2019	233,139		151,685	$ 5		262,865	(8,026)	(103,159)	81,454
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under the equity compensation plan (in shares)				453,817	4,338
Issuance of common stock under the equity compensation plan	0	$ 0
Stock-based compensation expense	10,203		10,203			10,203
Issuance of common stock for acquisition (in shares)				823,615
Issuance of common stock for acquisition	33,011		33,011			33,011
Distributions paid to noncontrolling interests	(601)								(601)
Change in cumulative foreign currency translation adjustment	6		6				6
Change in fair value of cash flow hedge, net of taxes	(18,764)		(18,764)				(18,764)
Amount of loss reclassified from accumulated OCI into income (prior period effective portion)	1,861		1,861				1,861
Net (loss) income	(12,734)		(20,797)					(20,797)	8,063
Ending balance (in shares) at Sep. 30, 2020				51,596,098
Ending balance, value at Sep. 30, 2020	246,121		157,205	$ 5		306,079	(24,923)	(123,956)	88,916
Beginning balance (in shares) at Jun. 30, 2020				51,554,760
Beginning balance, value at Jun. 30, 2020	233,256		147,808	$ 5		304,012	(26,098)	(130,111)	85,448
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under the equity compensation plan (in shares)				37,000	4,338
Issuance of common stock under the equity compensation plan	0	$ 0
Stock-based compensation expense	2,067		2,067			2,067
Distributions paid to noncontrolling interests	(601)								(601)
Change in cumulative foreign currency translation adjustment	11		11				11
Change in fair value of cash flow hedge, net of taxes	195		195				195
Amount of loss reclassified from accumulated OCI into income (prior period effective portion)	969		969				969
Other	(1)		(1)					(1)
Net (loss) income	10,225		6,156					6,156	4,069
Ending balance (in shares) at Sep. 30, 2020				51,596,098
Ending balance, value at Sep. 30, 2020	$ 246,121		$ 157,205	$ 5		$ 306,079	$ (24,923)	$ (123,956)	$ 88,916