Changes in Ownership Interest in Consolidated Subsidiaries (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CHANGES IN OWNERSHIP INTEREST IN CONSOLIDATED SUBSIDIARIES
Net loss attributable to American Renal Associates Holdings, Inc.	$ 90	$ 4,777	$ (8,178)	$ (10,479)	$ (572)	$ (734)	$ (23,659)	$ (3,802)	$ (13,790)	$ (28,767)	$ (4,597)
Increase (decrease) in paid-in capital for redemptions of equity of noncontrolling interests									4,735	(891)	231
Decrease in paid-in capital for the purchase of equity of noncontrolling interests and adjustments to ownership interest									(8,048)	(6,645)	(7,566)
Net transfers to noncontrolling interests									(3,313)	(7,536)	(7,335)
Net loss attributable to American Renal Associates Holdings, Inc., net of transfers to noncontrolling interests									$ (17,103)	$ (36,303)	$ (11,932)