Debt - Principal Payments on Debt (Detail) $ in Thousands	Sep. 30, 2018 USD ($)
Debt Disclosure [Abstract]
Remainder of 2018	$ 3,922
2019	3,605
2020	3,380
2021	21,667
2022 and thereafter	9,518
Total	42,092
Add: capital lease principal payments	135
Less: unamortized debt discount and debt issuance costs	(1,756)
Total	40,471
Less: current portion of long-term debt	(6,186)
Long-term debt, net of current portion	$ 34,285

Long-term Debt, Maturities, Repayments of Principal in Year Five and Thereafter

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Unamortized debt issuance and debt discount.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease 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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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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