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Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended			12 Months Ended			44 Months Ended
	Apr. 26, 2016	Mar. 31, 2018	Apr. 30, 2016	Mar. 31, 2014	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Jan. 31, 2011	May 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term					10 years
Aggregate intrinsic value of stock options exercised					$ 1,048	$ 4,825	$ 10,974
Unamortized stock-based compensation					$ 4,588			$ 4,588
Weighted-average vesting period					2 years 10 months 24 days
Cash dividend (in dollars per share)	$ 1.30
Cash dividend	$ 28,886
Unrecognized non-cash compensation costs	$ 38,877
Compensation costs recognition period, after plan modifications	12 months
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					5 years
American Renal Holdings Inc. 2005 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options to purchase outstanding (in shares)					0			0
Common stock reserved for issuance and remaining for future equity grants (in shares)					0			0
American Renal Associates Holdings, Inc. 2010 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options to purchase outstanding (in shares)					3,519,887			3,519,887
Common stock reserved for issuance and remaining for future equity grants (in shares)					0			0		3,606,251
Authorized additional stock options (in shares)				1,627,258
American Renal Associates Holdings, Inc. 2011 Stock Option Plan for Nonemployee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options to purchase outstanding (in shares)					34,350			34,350
Common stock reserved for issuance and remaining for future equity grants (in shares)					0			0	100,000
2016 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance and remaining for future equity grants (in shares)					1,437,563			1,437,563
Authorized additional stock options (in shares)			4,000,000
Common stock \| 2016 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested (in shares)					1,248,909			1,248,909
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested (in shares)					579,283	441,063		579,283
Unamortized stock-based compensation					$ 4,668			$ 4,668
Weighted-average vesting period					1 year
Awards granted (in shares)					324,801
Awards granted (in USD per share)					$ 10.19
Fair value of restricted stock vested					$ 2,950	$ 1,701	440
Restricted stock \| 2016 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested (in shares)					579,283			579,283
Market and Performance Based Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation					$ 192			$ 192
Performance and Time Based Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation					$ 4,397			$ 4,397
Executive \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Weighted-average vesting period					3 years
Awards granted (in shares)		95,000			51,500
Awards granted (in USD per share)		$ 22.33			$ 10.19
Vested Option Stockholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalent adjustments in the form of cash dividend equivalent payments (in dollars per share)								$ 1.30
Equitable adjustments in the form of cash dividend equivalent payments								$ 5,391
Vested Option Stockholders \| Term Loan Holdings LLC
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equitable adjustments in the form of cash dividend equivalent payments								2,524
Unvested Option Stockholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equitable adjustments in the form of cash dividend equivalent payments								$ 1,247
IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation due to modification							$ 11,749