Area of a real estate property.

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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Balance Type:	credit
Period Type:	instant

- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

+ Details

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

- 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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- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=cpa18_StudentHousinginBarcelonaSpainMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Subsequent Events (Details)			3 Months Ended
Subsequent Events (Details)	Aug. 04, 2020 USD ($) ft²	Jul. 16, 2020 USD ($)	Jun. 30, 2020 USD ($) ft²	Jul. 31, 2020 USD ($)	Mar. 31, 2020	Mar. 13, 2020 USD ($)
Subsequent Events
Additional reserves			$ 1,400,000
Accrual for noncontrolling interest			$ 2,600,000
Area of real estate property (sqft) \| ft²			9,600,000
Subsequent Event
Subsequent Events
Interest rate equal to the LIBOR (percentage)		1.05%
Amount awarded to other party	$ 2,600,000
Subsequent Event \| Student Housing in Barcelona, Spain
Subsequent Events
Area of real estate property (sqft) \| ft²	77,504
Line of Credit \| Affiliated Entity \| Subsequent Event
Subsequent Events
Unsecured line of credit		$ 25,000,000.0
Interest rate equal to the LIBOR (percentage)		1.05%
Construction Loans \| Student Housing in Barcelona, Spain
Subsequent Events
Unsecured line of credit						$ 22,500,000
Variable interest rate (percent)					2.10%
Construction Loans \| Subsequent Event \| Student Housing in Seville, Spain
Subsequent Events
Unsecured line of credit				$ 24,600,000
Variable interest rate (percent)				3.50%