Area of facility lease.

No definition available.

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- Definition

Lease commencement date.

+ References

No definition available.

+ Details

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- Definition

Number of lease renewal option.

+ References

No definition available.

+ Details

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- Definition

Operating lease abatement term.

+ References

No definition available.

+ Details

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- Definition

Operating leases income statement sublease income (loss).

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Short term and variable lease cost.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Sublease commencement date.

+ References

No definition available.

+ Details

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- Definition

Write-off lease receivable and prepaid commission assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	arav_
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- Definition

This item represents the deferred charge for an incentive or inducement granted by a lessor to a lessee, in order to motivate the lessee to enter the lease agreement, which incentive or inducement is to be recognized as a reduction of rental revenue over the lease term.

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- 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

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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

- Definition

Weighted average discount rate for operating lease calculated at point in time.

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash inflows from lease payments.

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- Details

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Leases - Additional Information (Detail) $ in Thousands	1 Months Ended				3 Months Ended		9 Months Ended
Leases - Additional Information (Detail) $ in Thousands	Aug. 31, 2020 USD ($) ft²	Oct. 31, 2018 ft²	Aug. 01, 2018 USD ($)	Mar. 31, 2017 ft² Lease	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Lessee Lease Description [Line Items]
Number of lease renewal option \| Lease				1
Cash paid for measurement of lease obligations for operating cash flows from operating leases							$ 2,000	$ 2,000
Short term and variable lease cost					$ 100	$ 100	300	400
Rent expense					$ 600	600	$ 1,900	1,900
Weighted average remaining lease term					4 years 1 month 6 days		4 years 1 month 6 days
Weighted average discount rate					7.75%		7.75%
Write down of sublease receivable balance and previously capitalized commission charges							$ 1,383
2479 E. Bayshore Blvd, Palo Alto, California [Member] \| Sublease Agreement [Member]
Lessee Lease Description [Line Items]
Operating facility lease area \| ft²		4,240
Lease commencement date		2018-10
Lease expires date		Aug. 31, 2020
North Carolina [Member]
Lessee Lease Description [Line Items]
Operating facility lease area \| ft²	4,128
Operating facility lease term	63 months
Operating lease abatement term	3 months
Cash paid for measurement of lease obligations for operating cash flows from operating leases	$ 9
1020 Marsh Road, Menlo Park, California [Member]
Lessee Lease Description [Line Items]
Operating facility lease area \| ft²				34,500
Lease commencement date				2017-08
Operating facility lease term				87 months
Lease agreement, one renewal option term				5 years
1020 Marsh Road, Menlo Park, California [Member] \| Sublease Agreement [Member] \| EVA Automation, Inc [Member]
Lessee Lease Description [Line Items]
Operating facility lease term			72 months
Operating lease abatement term			5 months
Sublease commencement date			Oct. 01, 2018
Abatement of base rent lease payment			$ 900
Write down of sublease receivable balance and previously capitalized commission charges							1,400
Operating lease sublease income (loss)					$ 47	600	(13)	1,900
Cash received from sublease						$ 600	$ 1,200	$ 1,400