Debt - Summary of Long Term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	May 04, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (565)
Financing obligations	5,099		$ 8,631
Total debt	171,539		105,460
Less: Current portion of long-term debt	0		(5,000)
Less: Current portion of financing obligations	(3,700)		(5,432)
Total long-term debt, net	167,839		95,028
Convertible Debt \| 1.25% Convertible Senior Notes
Debt Instrument [Line Items]
Principal	201,250		0
Unamortized debt discount	(34,245)		0
Unamortized debt issuance costs	(565)		0
Long-term debt	$ 166,440		0
Stated interest rate (as a percent)	1.25%	1.25%
Term Loan Facility
Debt Instrument [Line Items]
Principal	$ 0		97,500
Unamortized debt issuance costs	0		(671)
Long-term debt	0		96,829
Financing Obligations
Debt Instrument [Line Items]
Less: Current portion of financing obligations	$ (3,700)		$ (5,432)

Amount of short-term and long-term debt and lease obligation.

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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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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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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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