Debt instrument conversion obligation number of consecutive business days after consecutive trading day period.

No definition available.

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- Definition

Debt instrument conversion obligation period of consecutive trading days.

+ References

No definition available.

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- Definition

Debt instrument conversion obligation trading price as percentage of product common stock closing sale price and conversion rate.

+ References

No definition available.

+ Details

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- Definition

Debt instrument convertible initial conversion price per share of common stock.

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No definition available.

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- Definition

Debt instrument covenant minimum cash and cash equivalents.

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No definition available.

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- Definition

Debt instrument effective interest rate period.

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No definition available.

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- Definition

Debt instrument final payment.

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No definition available.

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- Definition

The final payment, expressed as a percentage of aggregate principal amount, under a debt agreement.

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No definition available.

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- Definition

Debt issuance costs allocated to equity component in reduction to additional paid in capital.

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No definition available.

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- Definition

Debt issuance costs allocated to liability component.

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No definition available.

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- Definition

Line of credit minimum interest description.

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Line of credit termination fee percentage.

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Revolving credit facility minimum interest payment percentage.

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No definition available.

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- Definition

Amount of increase (decrease) in additional paid in capital (APIC) resulting from recognition of deferred taxes for convertible debt with a beneficial conversion feature.

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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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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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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No definition available.

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Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

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Face (par) amount of debt instrument at time of issuance.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

+ References

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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Start date of debt instrument redemption period, in CCYY-MM-DD format.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount of the fees associated with providing collateral for the credit facility.

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Description of the fees for amounts available, but unused under the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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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 after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Additional Information (Detail)			1 Months Ended	3 Months Ended	6 Months Ended	9 Months Ended
Debt - Additional Information (Detail)	Aug. 02, 2019 USD ($)	May 02, 2017 USD ($)	Aug. 31, 2019 USD ($)	Sep. 30, 2019 USD ($) $ / shares	Jun. 30, 2019	Sep. 30, 2019 USD ($) d $ / shares shares	Dec. 31, 2018 USD ($)	Aug. 04, 2015 USD ($)
Debt Instrument [Line Items]
Debt extinguishment loss						$ (352,000)
Long-term debt, net				$ 40,070,000		$ 40,070,000	$ 3,640,000
Interest on final payment				4.75%		4.75%
Carrying value of term loan				$ 40,100,000		$ 40,100,000
Debt issuance costs						$ 161,000
Repaid In Year One [Member]
Debt Instrument [Line Items]
Debt instrument interest rate				3.00%		3.00%
Repaid In Year Two [Member]
Debt Instrument [Line Items]
Debt instrument interest rate				2.00%		2.00%
Repaid In Year Three [Member]
Debt Instrument [Line Items]
Debt instrument interest rate				1.00%		1.00%
Repaid In Year Four And Thereafter [Member]
Debt Instrument [Line Items]
Debt instrument interest rate				0.00%		0.00%
2015 Term Loan [Member]
Debt Instrument [Line Items]
Repayments of Lines of Credit						$ 7,700,000
Carrying value of term loan				$ 40,070,000		40,070,000
Liability component of Convertible Notes recorded as long-term debt				49,772,000		49,772,000
Mid Cap Financial Trust [Member] \| 2015 Term Loan [Member]
Debt Instrument [Line Items]
Term loan, maximum borrowings								$ 30,000,000.0
Final payment of borrowed amount			$ 2,700,000
Debt extinguishment loss						$ 400,000
Silicon Valley Bank [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Term loan, maximum borrowings	$ 20,000,000.0
Debt Instrument Maturity Date						Jan. 01, 2024
Debt Instrument Covenant Minimum Revenues						$ 80,000,000.0
Debt instrument interest rate description						Borrowings under the revolving credit facility accrue interest monthly at a floating interest rate equal to the greater of the prime rate or 5.50% per annum.
Unused portion of revolving line, percentage						0.25%
Revolver commitment amount				20,000,000.0		$ 20,000,000.0
Line of credit facility, fee description						unused revolving line facility fee equal to 0.25% per annum of the average unused portion of the revolving line. multiplied by the difference between the total amount available to be borrowed (the “Revolver Commitment Amount”) of $20.0 million and the greater of the average outstanding revolver balance and 25% of the Commitment Amount
Line of credit facility, minimum interest calculation as a percentage of revolving commitment amount						25.00%
Revolving credit facility and any related fees, description						Beginning on January 1, 2020, if the interest payment on the revolving credit facility is less than the amount of interest that would have been payable had the Company borrowed 25% of the Revolver Commitment Amount, then the Company will be required to pay the difference.
Silicon Valley Bank [Member] \| Revolving Credit Facility [Member] \| Repaid In Year One [Member]
Debt Instrument [Line Items]
Line of credit facility, termination fees, percentage						2.00%
Silicon Valley Bank [Member] \| Revolving Credit Facility [Member] \| Repaid In Year Two [Member]
Debt Instrument [Line Items]
Line of credit facility, termination fees, percentage						1.00%
Silicon Valley Bank [Member] \| Revolving Credit Facility [Member] \| Repaid In Year Three And Thereafter [Member]
Debt Instrument [Line Items]
Line of credit facility, termination fees, percentage						0.00%
Silicon Valley Bank [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Line of credit facility, collateral fees, amount						$ 10,000,000.0
Silicon Valley Bank [Member] \| 2015 Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt, net				$ 40,000,000.0		$ 40,000,000.0
Silicon Valley Bank [Member] \| 2019 Term Loan [Member]
Debt Instrument [Line Items]
Term loan, principal amount	40,000,000.0
Debt Instrument Maturity Date						Jan. 01, 2024
Long-term debt, net	$ 40,000,000.0
Debt instrument interest rate description						Borrowings under the 2019 term loan accrue interest monthly at a floating interest rate equal to the greater of the prime rate plus 1.5% or 6.5% per annum
Term loan, first periodic payment date	Feb. 01, 2021
Interest on final payment	4.75%
Term loan, payment description						interest-only period of 18 months, principal is due in 36 equal monthly installments
Silicon Valley Bank [Member] \| 2019 Term Loan [Member] \| Interest-Only-Strip [Member]
Debt Instrument [Line Items]
Term loan, Interest payment period	18 months
Silicon Valley Bank [Member] \| 2019 Term Loan [Member] \| Principal-Only-Strip [Member]
Debt Instrument [Line Items]
Term loan, Interest payment period	36 months
2024 Convertible Notes [Member]
Debt Instrument [Line Items]
Term loan, principal amount		$ 201,300,000
Debt Instrument Maturity Date		May 01, 2024
Debt instrument interest rate		3.375%		3.375%		3.375%
Debt instrument interest rate		3.375%		9.71%		9.71%
Debt instrument frequency of periodic payment					semi-annually
Net proceeds from offering of convertible senior notes		$ 194,800,000
Debt discount and issuance costs		6,500,000		$ 68,900,000		$ 68,900,000
Number of shares issued upon conversion of $1,000 debt principal amount \| shares						37.3413
Debt instrument convertible initial conversion price per share of common stock \| $ / shares				$ 26.78		$ 26.78
Number of days within 30 consecutive trading days in which the closing price of the entity's common stock must exceed the conversion price for the notes to be convertible into common stock \| d						20
Number of consecutive trading days during which the closing price of the entity's common stock must exceed the conversion price for at least 20 days in order for the notes to be convertible into common stock \| d						30
Percentage of the closing sales price of the entity's common stock that the conversion price must exceed in order for the notes to be convertible						130.00%
Number of consecutive business days immediately after any five consecutive trading day period during the note measurement period \| d						5
Number of consecutive trading days before five consecutive business days during the note measurement period \| d						10
Liability component of Convertible Notes recorded as long-term debt		136,700,000
Equity component of Convertible Notes recorded as additional paid-in capital		$ 64,500,000
Debt instrument effective interest rate period						7 years
Debt issuance costs						$ 6,500,000
Debt issuance costs allocated to liability component						4,400,000
Debt issuance costs allocated to equity component reduction to additional paid-in capital						2,100,000
Interest expense				$ 3,700,000		11,000,000.0
Amortization of debt discount				$ 2,000,000.0		$ 5,900,000
2024 Convertible Notes [Member] \| Repaid In Year Two [Member]
Debt Instrument [Line Items]
Number of days within 30 consecutive trading days in which the closing price of the entity's common stock must exceed the conversion price for the notes to be convertible into common stock \| d						20
Number of consecutive trading days during which the closing price of the entity's common stock must exceed the conversion price for at least 20 days in order for the notes to be convertible into common stock \| d						30
Percentage of the closing sales price of the entity's common stock that the conversion price must exceed in order for the notes to be convertible						130.00%
Debt instrument redemption date						May 06, 2020
Redemption price percentage of principal amount to be redeemed						100.00%
2024 Convertible Notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument conversion obligation trading price as percentage of product common stock closing sale price and conversion rate						98.00%