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Applicable interest rate on united states treasury securities.

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Cash payment of consent fee.

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Consent fee paid.

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Consent fee paid in kind.

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Debt covenant consolidated asset coverage ratio.

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Debt Disclosure [Line Items]

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Percentage of holders of notes needed to accelerate repayment should there be an event of default.

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Debt instrument covenant minimum capital expenditure.

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Debt instrument covenant net proceeds in excess of asset disposition to be used for redemption.

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Debt instrument covenant revenue cure period.

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Debt Instrument covenant unrestricted cash and unrestricted permitted investments maximum.

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Debt instrument debt default threshold for acceleration.

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Debt instrument excess cash flow repayment percentage.

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Debt Instrument, Interest Rate, Stated Percentage Increase.

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Debt Instrument, Premium Percentage

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Debt instrument revenue covenant.

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Debt instrument uncured period.

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Minimum operating cash flow amount.

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Percentage of consolidated revenue.

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

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Percentage of principal amount of debt redeemed.

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Fair value amount of debt instrument that was repurchased.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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LONG-TERM DEBT - Additional Information (Detail)			3 Months Ended				9 Months Ended
LONG-TERM DEBT - Additional Information (Detail)	Apr. 01, 2020	Jun. 27, 2019 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Mar. 31, 2021	Dec. 31, 2020
Debt Disclosure [Line Items]
Amortization of deferred financing fees			$ 1,000,000			$ 600,000	$ 2,800,000	$ 4,000,000
Write off unamortized deferred financing fees								$ 6,900,000
Senior Secured Notes
Debt Disclosure [Line Items]
Interest payable, Description							Interest is payable quarterly in arrears on the 30th day of each March, June, September and December, commencing September 30, 2019.
Maturity date		Jun. 30, 2024
Interest payable option, Description							The Senior Secured Notes will require cash interest payments at 9.875% for all interest periods after January 30, 2022.
Applicable interest rate on united states treasury securities		0.50%
Redemptions from asset dispositions		$ 55,000,000
Debt instrument redemption price percentage		2.00%
Redemption of senior secured notes			51,700,000				$ 51,700,000
Percentage of excess cash flow		75.00%
Minimum operating cash flow amount			$ (35,000,000)	$ (35,000,000)			$ (35,000,000)
Debt covenant, aggregate amount of capital expenditures						$ 20,000,000
Debt covenant, unrestricted cash and unrestricted permitted investments				$ 12,500,000	$ 12,500,000
Debt covenant, consolidated asset coverage ratio			1.60				1.60
Uncured period							15 days
Covenant compliance, percentage							25.00%
Percentage of consolidated revenue							15.00%
Debt instrument, revenue covenant							$ 30,000,000
Revenue - cure period							30 days
Interest rate increase percentage							13.50%
Consent fee paid							$ 5,000,000
Cash payment of consent fee							3,500,000
Consent fee paid in kind							$ 1,500,000
Senior Secured Notes \| Maximum
Debt Disclosure [Line Items]
Debt instrument redemption price percentage	11.50%
Debt covenant, consolidated asset coverage ratio			1.40	1.40			1.40
Senior Secured Notes \| Minimum
Debt Disclosure [Line Items]
Debt instrument redemption price percentage	9.875%
Debt instrument, acceleration of or failure to pay			$ 5,000,000				$ 5,000,000
Senior Secured Notes \| Forecast
Debt Disclosure [Line Items]
Debt covenant, consolidated asset coverage ratio										1.40
Senior Secured Notes \| Forecast \| Maximum
Debt Disclosure [Line Items]
Debt covenant, consolidated asset coverage ratio									1.60	1.40
Senior Secured Notes \| Redeemed Before June 27, 2021
Debt Disclosure [Line Items]
Debt instrument redemption price percentage		4.00%
Senior Secured Notes \| Redemption Date Through June 27, 2021
Debt Disclosure [Line Items]
Debt instrument redemption price percentage		11.50%
Senior Secured Notes \| Redeemed On Or After June 27, 2021 and Before June 27, 2022
Debt Disclosure [Line Items]
Debt instrument redemption price percentage		5.00%
Senior Secured Notes \| Redeemed On Or After June 27, 2021 and Before June 27, 2022 \| Maximum
Debt Disclosure [Line Items]
Debt instrument redemption price percentage	5.00%
Senior Secured Notes \| Redeemed On Or After June 27, 2021 and Before June 27, 2022 \| Minimum
Debt Disclosure [Line Items]
Debt instrument redemption price percentage	4.00%
Senior Secured Notes \| Redeemed On Or After June 27, 2022 and Before June 27, 2023
Debt Disclosure [Line Items]
Debt instrument redemption price percentage		3.00%
Senior Secured Notes \| Redeemed On Or After June 27, 2022 and Before June 27, 2023 \| Maximum
Debt Disclosure [Line Items]
Debt instrument redemption price percentage	3.00%
Senior Secured Notes \| Redeemed On Or After June 27, 2022 and Before June 27, 2023 \| Minimum
Debt Disclosure [Line Items]
Debt instrument redemption price percentage	2.00%
Senior Secured Notes \| Redeemed On Or After June 27, 2023
Debt Disclosure [Line Items]
Debt premium percentage		0.00%
Senior Secured Notes \| In Cash
Debt Disclosure [Line Items]
Long-term debt, interest rate		9.875%
Senior Secured Notes \| Option Through January 30, 2022 - In Cash
Debt Disclosure [Line Items]
Long-term debt, interest rate		7.50%	7.50%				7.50%
Senior Secured Notes \| Option Through January 30, 2022 - Payable in Kind
Debt Disclosure [Line Items]
Long-term debt, interest rate		4.00%	4.00%				4.00%
Senior Secured Notes \| Private Placement
Debt Disclosure [Line Items]
Long-term debt, principal amount		$ 385,000,000
Gross proceeds from the sale of the senior secured notes		371,500,000
Long-term debt, debt issuance costs		$ 7,000,000