Area of a real estate property.

No definition available.

Name:	us-gaap_AreaOfRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

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

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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

- 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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Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=autl_OfficeAndManufacturingSpaceinRockvilleMarylandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=autl_OrdinarySharesMember
Namespace Prefix:
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Subsequent Events (Details) $ / shares in Units, $ in Thousands		3 Months Ended	12 Months Ended
	Feb. 27, 2020 USD ($) ft² shares	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Jan. 27, 2020 $ / shares
Subsequent Event
Proceeds of issuance of ordinary shares, net of issuance costs		$ 0	$ 108,863	$ 156,920	$ 127,686
Subsequent Events \| Office Space in Rockville, Maryland
Subsequent Event
Area of property (sqft) \| ft²	27,502
Subsequent Events \| Ordinary shares
Subsequent Event
Number of shares issued in transaction (shares) \| shares	7,250,000
Per share price of issuance (usd per share) \| $ / shares						$ 11.00
Proceeds of issuance of ordinary shares, net of issuance costs	$ 75,000