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

No definition available.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

No definition available.

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Data Type:	xbrli:monetaryItemType
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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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

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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.

No definition available.

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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingAndBuildingImprovementsMember
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Name:	wpc_FiniteLivedIntangibleLiabilitiesByMajorClassAxis=wpc_BelowMarketLeaseMember
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Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=wpc_IndustrialInPleasantPrairieWisconsinMember
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Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=wpc_FuneralHomeVariousSpainMember
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Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=wpc_RetailInVariousDenmarkMember
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