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Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

No definition available.

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

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

No definition available.

Name:	atel_PropertyOnOperatingLeasesNet
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Property subject to or available for operating lease accumulated depreciation, additions.

No definition available.

Name:	atel_PropertySubjectToOrAvailableForOperatingLeaseAccumulatedDepreciationAdditions
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Property subject to or available for operating lease accumulated depreciation, reclassifications or dispositions.

No definition available.

Name:	atel_PropertySubjectToOrAvailableForOperatingLeaseAccumulatedDepreciationReclassificationsOrDispositions
Namespace Prefix:	atel_
Data Type:	xbrli:monetaryItemType
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Property subject to or available for operating lease, additions.

No definition available.

Name:	atel_PropertySubjectToOrAvailableForOperatingLeaseAdditions
Namespace Prefix:	atel_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Property subject to or available for operating lease additions, gross.

No definition available.

Name:	atel_PropertySubjectToOrAvailableForOperatingLeaseAdditionsGross
Namespace Prefix:	atel_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Property subject to or available for operating lease, reclassifications or dispositions.

No definition available.

Name:	atel_PropertySubjectToOrAvailableForOperatingLeaseReclassificationsOrDispositions
Namespace Prefix:	atel_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Property subject to or available for operating lease reclassifications or dispositions, gross.

No definition available.

Name:	atel_PropertySubjectToOrAvailableForOperatingLeaseReclassificationsOrDispositionsGross
Namespace Prefix:	atel_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-3

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