Debt instrument percentage of projected financial performance target.

No definition available.

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- Definition

Debt covenant percentage of projected revenue to be achieved.

+ References

No definition available.

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- Definition

Debt Final Payment Percentage Of Aggregate Principal Amount

+ References

No definition available.

+ Details

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- Definition

Line of credit facility, termination fee.

+ References

No definition available.

+ Details

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- Definition

Termination of line of credit facility.

+ References

No definition available.

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Period Type:	duration

- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Publisher FASB
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-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

+ References

No definition available.

+ Details

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
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Balance Type:	debit
Period Type:	duration

- Definition

Fair value portion of warrants not settleable in cash classified as equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Details

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Term Notes - Additional Information (Detail) - USD ($)		9 Months Ended
Term Notes - Additional Information (Detail) - USD ($)	Feb. 29, 2020	Sep. 30, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Feb. 28, 2018
Debt Instrument [Line Items]
Debt Amount		$ 16,500,000	$ 13,334,000
Debt, final payment amount		$ 1,568,000
Loan and Security Agreement
Debt Instrument [Line Items]
Debt, final payment as percentage of original aggregate principal amount		6.75%
Debt, final payment amount		$ 1,600,000				$ 1,000,000
Proceeds of supplemental term loan	$ 4,300,000
Debt payments description		The Amended Credit Facility provides an interest-only payment period which will end on (a) June 30, 2021, if the Company’s revenue for the trailing 12-month period ended June 30, 2021 is not at least 75% of the Company’s projections; (b) December 31, 2021, if the Company achieves the financial performance target referred to in clause (a), but does not obtain premarket approval of the Company’s C2 catheters from the FDA by such date and/or the Company’s trailing 12-month revenue for the period ending December 31, 2021 is not at least 75% of the Company’s projections; or (c) June 30, 2022, if the Company achieves the milestones referred to in clauses (a) and (b).
Loan and Security Agreement \| Supplemental Term Loan
Debt Instrument [Line Items]
Debt Amount	16,500,000
Debt interest rate		3.50%
Proceeds of supplemental term loan, net of final balloon payment fee	$ 3,300,000
Debt maturity date	Dec. 01, 2023
Loan and Security Agreement \| Interest Payment End On June 30, 2021
Debt Instrument [Line Items]
Debt instrument percentage of projected revenue to be achieved	75.00%
Loan and Security Agreement \| Interest Payment End On December 31, 2021
Debt Instrument [Line Items]
Debt instrument percentage of projected financial performance target	75.00%
Loan and Security Agreement \| Minimum
Debt Instrument [Line Items]
Debt interest rate		1.75%
Loan and Security Agreement \| Minimum \| Prime Rate \| Supplemental Term Loan
Debt Instrument [Line Items]
Debt interest rate basis	1.25%
Loan and Security Agreement \| Maximum
Debt Instrument [Line Items]
Debt interest rate basis		2.75%
Loan and Security Agreement \| Maximum \| Supplemental Term Loan
Debt Instrument [Line Items]
Debt interest rate	3.50%
Loan and Security Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Termination of line of credit facility	$ 2,000,000
Loan and Security Agreement \| Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Line of credit facility termination fee	$ 100,000
Loan and Security Agreement \| Silicon Valley Bank
Debt Instrument [Line Items]
Debt, warrants issued		34,440
Debt, fair value of warrants issued		$ 100,000
Loan and Security Agreement \| Silicon Valley Bank \| Short Term Notes
Debt Instrument [Line Items]
Debt Amount						15,000,000
Loan and Security Agreement \| Silicon Valley Bank \| Short Term Notes \| Tranche One
Debt Instrument [Line Items]
Debt Amount					$ 10,000,000
Loan and Security Agreement \| Silicon Valley Bank \| Short Term Notes \| Tranche Two
Debt Instrument [Line Items]
Debt Amount				$ 5,000,000
Loan and Security Agreement \| Silicon Valley Bank \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt Amount						$ 2,000,000