LONG-TERM DEBT - Outstanding Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Less deferred financing costs, net of accumulated amortization	$ (10,328)	$ (14,657)
Total debt	391,441	321,032
Less current maturities	(1,769)	(317)
Total long-term debt	389,672	320,715
8.500% Senior Secured Notes due 2029
Debt Instrument [Line Items]
Long-term debt, gross	400,000
9.875%/11.500% Senior Secured PIK Toggle Notes, due June 2024
Debt Instrument [Line Items]
Long-term debt, gross		335,328
Insurance and vehicle financing
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,769	$ 361

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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