Debt - Principal Payments on Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
2019	$ 3,250
2020	47
2021	2,414
2022	15,148
2023 and thereafter	28,447
Total	49,306
Add: capital lease principal payments	126	$ 222
Less: debt discount	(3,857)	(2,023)
Total	45,575	41,073
Less: current portion of long-term debt	(3,276)	(3,306)
Long-term debt, net of current portion	$ 42,299	$ 37,767

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

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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 accumulated amortization, of debt discount.

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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 fourth 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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