The costs related to asset management fees paid to affiliates during the reporting period.

No definition available.

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- Definition

Uncollected Rent Receivable

+ References

No definition available.

+ Details

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Namespace Prefix:	cpa18_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

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Balance Type:	debit
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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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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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- Definition

Amount of the adjustment to rental revenues to measure escalating leasing revenues on a straight line basis.

+ References

No definition available.

+ Details

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- Details

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Period Type:

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Period Type:

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Segment Reporting - Narratives (Details) $ in Thousands	3 Months Ended		6 Months Ended
Segment Reporting - Narratives (Details) $ in Thousands	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)
Segment Reporting Information
Number of reportable segments \| segment			3
Accounts receivable written off during the period			$ 2,800
Uncollected rent receivable	$ 3,000		3,000
Allowance for credit losses			4,900
Asset management fees	2,878	$ 2,859	5,880	$ 5,727
Asset management fees
Segment Reporting Information
Asset management fees	2,900	2,900	5,900	5,700
Net Lease \| Operating Segments
Segment Reporting Information
Straight line rent adjustment	300	$ 800	1,000	$ 1,700
Lease revenues — net-leased
Segment Reporting Information
Accounts receivable written off during the period			7,000
Uncollected rent receivable	$ 400		$ 400