Debt instrument amortization period after interest payments period.

No definition available.

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- Definition

Debt instrument interest only payment period upon first draw of funds.

+ References

No definition available.

+ Details

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Namespace Prefix:	arvn_
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Balance Type:	na
Period Type:	duration

- Definition

Debt instrument interest payments term.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Debt instrument maturity month and year.

+ References

No definition available.

+ Details

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Namespace Prefix:	arvn_
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Balance Type:	na
Period Type:	duration

- Definition

Debt instrument maximum borrowing capacity.

+ References

No definition available.

+ Details

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Namespace Prefix:	arvn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of liquidated damages.

+ References

No definition available.

+ Details

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

- Definition

Percentage of maximum funding on project costs.

+ References

No definition available.

+ Details

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

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

+ Details

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

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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+ Details

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

- Definition

Decrease for amounts of indebtedness forgiven by the holder of the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

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

- Definition

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

+ References

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-Publisher FASB
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+ Details

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

- Definition

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

+ References

+ Details

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

- Definition

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

+ References

+ Details

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

- 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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Balance Type:	na
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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
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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Long-Term Debt - Additional Information (Details) - USD ($)	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Aug. 31, 2013	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2014
Debt Instrument [Line Items]
Debt instrument, outstanding amount				$ 2,000,000		$ 2,000,000
Amortization of debt discount							$ 7,210
Interest expense, Debt				$ 16,250	$ 22,903	$ 48,750	$ 69,319
2014 Assistance Agreement \| State of Connecticut
Debt Instrument [Line Items]
Debt instrument maturity month and year								2024-01
Debt instrument face amount								$ 2,500,000
Percentage of liquidated damages								7.50%
2018 Assistance Agreement \| State of Connecticut
Debt Instrument [Line Items]
Debt instrument, interest rate per annum	3.25%
Debt instrument maturity month and year	2028-09
Debt instrument face amount	$ 2,000,000.0
Percentage of liquidated damages	7.50%
Percentage of maximum funding on total project costs		50.00%
Debt instrument interest payments term	60 months
Debt instrument amortization period after interest payments period	120 months
2018 Assistance Agreement \| State of Connecticut \| Maximum
Debt Instrument [Line Items]
Debt instrument face amount		$ 2,000,000.0
Forgiveness of funding on achieving certain employment conditions	$ 1,000,000.0
Loan Agreement \| Connecticut Innovations, Inc. \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, maximum borrowing capacity			$ 750,000
Debt instrument, frequency of periodic payment						monthly
Debt instrument, interest rate per annum			7.50%
Debt instrument, interest only payment period upon first draw of funds			10 months
Debt instrument, date of first required payment			Jun. 01, 2015
Debt instrument, maturity date			Jul. 31, 2019
Loan Agreement \| Connecticut Innovations, Inc. \| Secured Debt \| Leasehold Improvements
Debt Instrument [Line Items]
Debt instrument, maximum borrowing capacity			$ 100,000