Long-Term Debt - Activity Relating to Third-Party Fees and Costs, Lender Fees and Discount (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)
Debt Disclosure [Abstract]
At beginning of year	$ 11,460
Amortization expense through March 16, 2018	(520)
Add: Second amendment refinancing costs	1,687
Less: Debt extinguishment costs	(3,079)
Less: Amortization expense after refinancing	(645)
At end of period	$ 8,903

Amount of accumulated amortization of debt issuance costs.

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Amount of amortization expense attributable to debt issuance costs.

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

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Gross amount of debt extinguished.

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The cash outflow for loan and debt issuance costs.

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