CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	$ (1,749)	$ 23,440	$ 38,133
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	86,795	80,607	72,899
Amortization of operating lease right-of-use assets	67,915	66,842	0
Equity in earnings of joint ventures, net of dividends	1,577	248	13,469
Amortization and write off of deferred financing costs and loan discount	4,413	4,184	3,898
Loss (gain) on sale and disposal of equipment and other	1,200	2,383	(2,054)
Gain on extinguishment of debt	(4,047)	0	0
Gain on re-measurement of pre-existing interest	0	(768)	(39,539)
Loss on impairment	4,170	0	3,937
Amortization of cash flow hedge	3,448	0	0
Non-cash change in fair value of interest rate hedge	2,528	0	0
Stock-based compensation	12,405	8,730	7,662
Other non cash item in other expenses	242	(371)	0
Change in value of contingent consideration	0	(3,123)	1,749
Changes in operating assets and liabilities, net of assets acquired and liabilities assumed in purchase transactions:
Accounts receivable	25,206	(17,482)	2,145
Other current assets	6,588	(3,557)	(9,248)
Other assets	(5,425)	(2,326)	(1,687)
Deferred taxes	(611)	(3,888)	(6,935)
Operating lease liability	(53,906)	(66,831)	0
Deferred rent	0	0	6,312
Deferred revenue	37,941	(1,082)	(208)
Accounts payable, accrued expenses and other liabilities	45,069	17,316	26,221
Net cash provided by operating activities	233,759	104,322	116,754
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of imaging facilities	(31,265)	(27,150)	(73,192)
Equity investments at fair value	0	(143)	(2,200)
Purchase of property and equipment	(94,172)	(74,153)	(72,180)
Proceeds from sale of equipment	828	1,160	2,575
Proceeds from the sale of equity interests in a joint venture	0	132	0
Proceeds from sale of internal use software	0	0	248
Nulogix return of capital	0	792	0
Equity contributions in existing and purchase of interest in joint ventures	(1,635)	(103)	(2,000)
Net cash used in investing activities	(126,244)	(99,465)	(146,749)
CASH FLOWS FROM FINANCING ACTIVITIES
Principal payments on notes and leases payable	(3,562)	(6,494)	(6,072)
Payments on term loan debt	(43,296)	(40,742)	(33,830)
Additional deferred finance costs on revolving loan amendment	(741)	0	0
Proceeds from debt issuance, net of issuance costs	0	97,144	0
Proceeds from paycheck protection program loans	4,023	0	0
Distributions paid to noncontrolling interests	(1,985)	(3,057)	(1,427)
Proceeds from sale of noncontrolling interest	0	5,275	0
Contributions from noncontrolling partners	0	750	2,640
Proceeds from revolving credit facility	250,900	261,200	204,300
Payments on revolving credit facility	(250,900)	(289,200)	(176,300)
Purchase of noncontrolling interests	0	0	(200)
Proceeds from issuance of common stock upon exercise of options	0	75	20
Net cash (used in) provided by financing activities	(45,561)	24,951	(10,869)
EFFECT OF EXCHANGE RATE CHANGES ON CASH	(101)	(32)	(69)
NET INCREASE (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	61,853	29,776	(40,933)
CASH AND CASH EQUIVALENTS, beginning of period	40,165	10,389	51,322
CASH AND CASH EQUIVALENTS, end of period	102,018	40,165	10,389
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid during the period for interest	39,521	46,254	37,016
Cash paid during the period for income taxes	5,069	5,884	4,933
Equipment acquired and leasehold improvements	52,000	51,700	47,800
Capital lease debt	20	100	6,700
Gain (loss) on equity method investment		(134)
Contingent consideration liability adjustment	0	(3,123)	1,749
Noncontrolling Interests
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	13,091	8,684	5,890
Radnet, Inc. Stockholders' Equity
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	$ (14,840)	14,756	32,243
Variable Interest Entity, Not Primary Beneficiary | Medical Arts Radiology
Adjustments to reconcile net income to net cash provided by operating activities:
Change in value of contingent consideration			1,700
Contingent consideration liability adjustment			$ 1,700
Business consideration liability adjustment recorded amount		$ 2,400