Debt Financing - Summary of Long-Term Debt, Net of Unamortized Debt Discount and Issuance Costs (Detail) - Build to Suit Obligation $ in Thousands	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Build-to-suit obligation principal amount	$ 10,253
Build-to-suit obligation Purchase Option Fees	1,419
Less: Unamortized Purchase Option Fees	(768)
Unamortized fair value of free-standing warrants	(97)
Unamortized debt discount	(147)
Unamortized debt issuance costs	(11)
Build-to-suit obligation, current portion	4,554
Build-to-suit obligation, long-term portion, net of debt issuance costs and discount	6,095
Build-to-suit obligation, net of debt issuance costs and discount	$ 10,649

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 discount.

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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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