FAIR VALUE MEASUREMENTS - Fair Value of Financial Instruments Not Recorded at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
5.375% senior notes due 2027 | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, interest rate, stated percentage	5.375%
Carrying Value | Fair Value, Nonrecurring | 5.375% senior notes due 2027
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	$ 472,452	$ 471,644
Carrying Value | Fair Value, Nonrecurring | Revolving credit facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	92,000	84,000
Fair Value | Fair Value, Nonrecurring | 5.375% senior notes due 2027
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	501,791	501,439
Fair Value | Fair Value, Nonrecurring | Revolving credit facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, fair value	$ 92,000	$ 84,000