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STOCKHOLDERS' EQUITY - Narrative (Detail) - USD ($)	3 Months Ended		6 Months Ended
STOCKHOLDERS' EQUITY - Narrative (Detail) - USD ($)	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense, stock options	$ 0		$ 0
Fair value of stock awards vested	887,000		5,292,000
Stock Options
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense	0	$ 0	0	$ 0
Aggregate intrinsic value of options exercised	448,000		448,000
Restricted Stock, Restricted Stock Units And Performance Stock Units
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense	3,044,000	1,763,000	5,928,000	3,277,000
Restricted Stock
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense	108,000		$ 108,000
Restricted Stock \| Non Employee Director
Limited Partners' Capital Account [Line Items]
Options, vesting period			3 years
Restricted Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense	5,315,000		$ 5,315,000
Performance Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense	9,006,000		$ 9,006,000
Weighted average \| Restricted Stock
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation, weighted average period			2 years 3 months 18 days
Weighted average \| Restricted Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation, weighted average period			1 year 10 months 24 days
Weighted average \| Performance Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation, weighted average period			1 year 10 months 24 days
2016 Plan
Limited Partners' Capital Account [Line Items]
Options granted, term			10 years
2016 Plan \| Minimum
Limited Partners' Capital Account [Line Items]
Options, vesting period			1 year
2016 Plan \| Maximum
Limited Partners' Capital Account [Line Items]
Options, vesting period			4 years
Amended and Restated 1997 Employee Stock Purchase Plan
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense	$ 72,000	$ 56,000	$ 128,000	$ 103,000
Class A Common Stock \| 2016 Plan
Limited Partners' Capital Account [Line Items]
Common stock, authorized shares	2,250,000		2,250,000
Number of shares available for future grant	947,000		947,000
Class A Common Stock \| 2006 Incentive Plan
Limited Partners' Capital Account [Line Items]
Common stock, additional authorized shares			2,723,000