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STOCKHOLDERS' EQUITY - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 19, 2024	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Limited Partners' Capital Account [Line Items]
Expiration period					10 years
Unrecognized stock-based compensation, weighted average period					2 years 2 months 12 days
Fair value of stock awards vested			$ 5,396		$ 5,396
Stock Options
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense			136	$ 141	404	$ 443
Unrecognized stock-based compensation expense, stock options			1,124		1,124
Aggregate intrinsic value of options exercised			0		$ 0
Restricted Stock | Non Employee Director
Limited Partners' Capital Account [Line Items]
Award vesting period					3 years
Restricted Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense			7,956		$ 7,956
Restricted Stock Unit | Non Employee Director
Limited Partners' Capital Account [Line Items]
Award service period					3 years
Restricted Stock Awards, Restricted Stock Units And Performance Stock Units
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense			3,539	2,338	$ 10,676	6,563
Performance Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense			10,223		$ 10,223
Market-based Performance Stock Units
Limited Partners' Capital Account [Line Items]
Weighted average fair value of market-based performance (in dollars per share)					$ 118.64
Risk-free interest rate					3.95%
Expected volatility					25.10%
Minimum
Limited Partners' Capital Account [Line Items]
Award vesting period					1 year
Maximum
Limited Partners' Capital Account [Line Items]
Award vesting period					5 years
Weighted average | Restricted Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation, weighted average period					2 years
Weighted average | Performance Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation, weighted average period					1 year 8 months 12 days
Amended and Restated 1997 Employee Stock Purchase Plan
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense			$ 196	$ 145	$ 568	$ 428
Class A Common Stock
Limited Partners' Capital Account [Line Items]
Sale of stock, number of shares issued	5,175	5,175
Public offering price (in dollars per share)		$ 100.00		$ 100.00		$ 100.00
Sale of stock, net proceeds		$ 496,569
Common stock, authorized shares (in shares)							4,000
Class A Common Stock | Amended 2016 Plan
Limited Partners' Capital Account [Line Items]
Common stock, authorized shares (in shares)							1,750
Class A Common Stock | 2016 Plan
Limited Partners' Capital Account [Line Items]
Common stock, authorized shares (in shares)							2,250
Number of shares available for future grant (in shares)			2,018		2,018
Class A Common Stock | 2006 Incentive Plan
Limited Partners' Capital Account [Line Items]
Common stock, additional authorized shares (in shares)							2,723

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