No definition available.

Name:	us-gaap_DiscontinuedOperationAdditionalDisclosuresAbstract
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- Definition

This element represents the applicable amount of income taxes or benefit realized on the gain (loss) on sale of properties during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.3-15.(a)(1)(ii))
-URI http://asc.fasb.org/extlink&oid=6875705&loc=d3e641549-123027

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

- Definition

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Publisher FASB
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-Topic 944
-SubTopic 360
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=117337397&loc=d3e23415-158514

+ Details

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

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

+ Details

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

- Definition

The cash inflow associated with the collection, including prepayments, of loans receivable issued for financing of goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

+ Details

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

- Definition

Amount of cash inflow for the sale of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Gain (Loss) From Collection Of Loan Receivable

+ References

No definition available.

+ Details

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

- Definition

Number Of Property Disposed Of

+ References

No definition available.

+ Details

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Namespace Prefix:	wpc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of properties sold during the period.

+ References

No definition available.

+ Details

Name:	wpc_NumberofPropertiesSold
Namespace Prefix:	wpc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=srt_HotelMember
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Property Dispositions - Narratives (Details) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
Property Dispositions - Narratives (Details) $ in Thousands	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($) property	Jun. 30, 2019 USD ($) property	Jun. 30, 2018 USD ($) property	Jun. 30, 2019 USD ($) property	Jun. 30, 2018 USD ($) property	Apr. 30, 2018 property
Discontinued Operation Additional Disclosures
Proceeds from repayment of loan receivable	$ 9,300				$ 9,574	$ 362
Loss from the collection of loan	$ 100
Purchases of real estate					289,766	$ 269,890
Operating Lease
Discontinued Operation Additional Disclosures
Gain (loss) on sale of real estate, net of tax		$ 6,300
Number of properties disposed of \| property		23
Purchases of real estate		$ 85,500			$ 308,000
Properties disposed of by sale
Discontinued Operation Additional Disclosures
Number of properties sold \| property			4	2	5	7
Proceeds from the sale of properties			$ 7,700	$ 42,000	$ 12,600	$ 77,700
Gain (loss) on sale of real estate, net of tax			$ (300)	5,600	$ 700	12,300
Gain on sales of real estate, applicable tax				$ 1,200		$ 1,200
Properties disposed of by sale \| Land, buildings and improvements
Discontinued Operation Additional Disclosures
Number of properties sold \| property					1
Properties disposed of by sale \| Land, buildings and improvements \| Hotel
Discontinued Operation Additional Disclosures
Number of real estate properties \| property							1