Members' Capital (Distributions to Other Members) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Distribution Made to Limited Liability Company (LLC) Member [Line Items]
Distributions	$ 513	$ 513	$ 1,026	$ 1,026
Weighted average number of Units outstanding	2,565,749	2,565,749	2,565,749	2,565,749
Other Members [Member]
Distribution Made to Limited Liability Company (LLC) Member [Line Items]
Distributions	$ 513	$ 513	$ 1,026	$ 1,026
Weighted average number of Units outstanding	2,565,749	2,565,749	2,565,749	2,565,749
Weighted average distributions per Unit	$ 0.20	$ 0.20	$ 0.40	$ 0.40

Weighted average number of limited liability company units outstanding determined by relating the portion of time within a reporting period that limited liability company units have been outstanding to the total time in that period.

No definition available.

+ Details

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Namespace Prefix:	cik0001640982_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of equity impact of cash distributions declared to unit-holder of limited liability company (LLC).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=125520817&loc=d3e70191-108054

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

+ Details

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

- Definition

Per unit of ownership amount of cash distributions paid to unit-holder of a limited liability company (LLC).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

+ Details

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- 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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Data Type:	xbrli:stringItemType
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- Details

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Balance Type:
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