Leasehold Improvements

No definition available.

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Period Type:	duration

- Definition

Lessee, Operating Lease, Rent Free Period

+ References

No definition available.

+ Details

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

- Definition

Operating Lease, Rent Free Period

+ References

No definition available.

+ Details

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

- Definition

Amount of gain (loss) on termination of lease before expiration of lease term.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 40
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121604053&loc=SL77918607-209975

+ Details

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

- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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

- Definition

This item represents a receivable for an incentive or inducement contractually stipulated between parties to a lease whereby the lessor has committed to provide the entity (lessee) with a cash payment as inducement to enter the lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=121549951&loc=d3e40019-112707

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121549951&loc=d3e40010-112707

+ Details

Name:	us-gaap_LeaseIncentiveReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6812-107765

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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

- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

+ Details

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

- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Commitments and Contingencies - (Narratives) (Details) $ in Thousands	1 Months Ended		3 Months Ended			9 Months Ended	12 Months Ended
	Oct. 31, 2018	Sep. 30, 2017	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($) unit	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2018
Loss Contingencies
Gain on termination of operating lease					$ 0	$ 0	$ 160	$ 0
Lease incentive receivable			$ 1,200
Rent expense					$ 500	$ 900
Imperial (Forest House) Limited
Loss Contingencies
Gain on termination of operating lease			$ 1,300
Imperial (Forest House) Limited \| Building
Loss Contingencies
Lease term (in years)							10 years
Imperial (Forest House) Limited \| Additional Space
Loss Contingencies
Lease term (in years)							15 months
Catapult Manufacturing Center \| Building
Loss Contingencies
Rent free period (in months)		6 months
Laboratory Space In White City, London
Loss Contingencies
Leasehold improvements, gross							$ 6,700
Laboratory Space In White City, London \| Building
Loss Contingencies
Lease term (in years)									10 years
Manufacturing Space In Enfield, United Kingdom \| Building
Loss Contingencies
Lease term (in years)						15 years
Number of units (units) \| unit						3
Leasehold Improvements								$ 4,100
Office Space In Rockville, Maryland \| Building
Loss Contingencies
Gain on termination of operating lease				$ 200
Operating lease rent free period	5 years
Office And Manufacturing Space in Rockville, Maryland
Loss Contingencies
Leasehold improvements, gross							$ 2,400