Deferred federal tax remeasurement rate.

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Deferred federal tax remeasurement value.

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- Definition

Interest expense threshold percentage of adjusted taxable income beyond which interest expense is deductible.

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No definition available.

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Net operating loss expiration period.

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Net operating loss limitation.

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Operating losses carryforward indefinitely with no carryback as percentage of taxable income.

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No definition available.

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Operations and summary of significant accounting policies.

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Period of increase in net operating loss limitation.

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No definition available.

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Refundable unused alternative minimum tax credit carryforward percentage.

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Refundable unused alternative minimum tax credit carryforward valuation allowance.

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Refundable unused alternative minimum tax credit carryforward, valuation allowance, year fully refunded by.

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No definition available.

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Refundable unused alternative minimum tax credit carryforward years.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Fair value of financial and nonfinancial obligations.

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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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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Summary of Significant Accounting Policies - Additional Information 3 (Detail) - USD ($)		1 Months Ended	2 Months Ended	3 Months Ended	7 Months Ended	9 Months Ended		12 Months Ended
	Dec. 31, 2017	Aug. 13, 2018	Sep. 30, 2018	Sep. 30, 2017	Aug. 13, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Operations And Summary Of Significant Accounting Policies [Line Items]
Federal statutory rate			21.00%			21.00%
Operating losses carryforward indefinitely with no carryback as percentage of taxable income						80.00%
Interest expense threshold percentage of adjusted taxable income beyond which interest expense is deductible						30.00%
Deferred federal tax, Remeasurement Rate						21.00%
Refundable unused AMT credit carryforward, Percentage						50.00%
Refundable unused alternative minimum tax credit carryforward years						2018 through 2020
Refundable unused AMT credit carryforward, year fully refunded by						2021
Net operating loss limitation						$ 3,300,000
Period of increase in net operating loss limitation						5 years
Net operating loss expiration period						20 years
Net Fair Value Presented in the Consolidated Balance Sheet, Liabilities Derivatives - current			$ 2,849,000			$ 2,849,000
Fixed Rate Debt
Operations And Summary Of Significant Accounting Policies [Line Items]
Long-term debt, including current portion, Carrying Value			816,300,000			816,300,000
Level 2 \| Fixed Rate Debt
Operations And Summary Of Significant Accounting Policies [Line Items]
Long-term debt, including current portion, Fair Value			850,000,000			850,000,000
Predecessor
Operations And Summary Of Significant Accounting Policies [Line Items]
Federal statutory rate		21.00%		35.00%	21.00%		35.00%	35.00%
Deferred federal tax, Remeasurement Value	$ 140,400,000
Refundable unused AMT credit carryforward, Valuation Allowance	19,100,000							$ 19,100,000
Derivative financial instruments, asset	$ 1,300,000							$ 1,300,000
Predecessor \| Fair Value, Measurements, Recurring \| Level 3
Operations And Summary Of Significant Accounting Policies [Line Items]
Financial assets			0			0
Financial liabilities			$ 0			$ 0