LONG-TERM DEBT - Senior Unsecured Notes (Details) - Senior Unsecured Notes - 2016 Senior Unsecured Notes - USD ($) $ in Millions	1 Months Ended
Oct. 31, 2016	Sep. 30, 2021
Debt Instrument [Line Items]
Loan face amount	$ 500.0
Interest rate, stated	7.875%	7.875%
Redeemable in whole or in part
Debt Instrument [Line Items]
Redemption price (as a percent)	100.00%
Redeemable rate upon change of control
Debt Instrument [Line Items]
Redemption price (as a percent)	101.00%
Redeemable rate upon certain asset sales
Debt Instrument [Line Items]
Redemption price (as a percent)	100.00%
Redemption of debt instrument in period four
Debt Instrument [Line Items]
Redemption price (as a percent)	100.00%

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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