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

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 470
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-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ 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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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Data Type:	xbrli:dateItemType
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
-Subparagraph (SX 210.5-02.22(a)(3))
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-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument minimum liquidity ratio financial covenant.

+ References

No definition available.

+ Details

Name:	vray_DebtInstrumentMinimumLiquidityRatioFinancialCovenant
Namespace Prefix:	vray_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument prepayment premium percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	vray_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Final payment percentage of original principal amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	vray_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Minimum trailing period for revenue thresholds under minimum revenue financial covenant.

+ References

No definition available.

+ Details

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Namespace Prefix:	vray_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of installments.

+ References

No definition available.

+ Details

Name:	vray_NumberOfInstallments
Namespace Prefix:	vray_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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- Details

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Subsequent Events - Additional Information (Detail) - SVB Term Loan $ in Millions		1 Months Ended	9 Months Ended
	Oct. 30, 2020 USD ($) Installment	Dec. 31, 2018 USD ($) Installment	Sep. 30, 2020 USD ($)
Subsequent Event [Line Items]
Total principal amount		$ 56.0	$ 56.0
Frequency of periodic payment			monthly
Number of installments \| Installment		36
Debt instrument description			Beginning on December 1, 2020 (or June 1, 2021, if the Company achieves a trailing twelve-month revenue of at least a specified amount and elects to apply such later date), the Company will make thirty-six equal monthly payments of principal (or thirty equal payments, if the Company so elects).
Debt maturity date		Dec. 01, 2023
Debt instrument fixed interest rate		6.30%	6.30%
Final payment percentage of principal amount		3.15%	3.15%
Debt instrument minimum liquidity ratio financial covenant			175.00%
Debt instrument prepayment premium percentage			2.00%
Subsequent Event
Subsequent Event [Line Items]
Total principal amount	$ 58.0
Frequency of periodic payment	monthly
Number of installments \| Installment	36
Debt instrument description	revise the thirty-six equal monthly payments of principal to begin on November 1, 2022
Debt maturity date	Oct. 01, 2025
Debt instrument interest rate	5.65%
Final payment percentage of principal amount	3.70%
Debt instrument minimum liquidity ratio financial covenant	170.00%
Minimum trailing period for revenue thresholds under minimum revenue financial covenant	12 months
Debt instrument prepayment premium percentage	3.00%
Debt instrument final payment	$ 0.8
Prime Rate \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument floating rate	2.40%