Pro forma basic earnings per share or earnings per unit, which is commonly presented in initial public offerings based on the terms of the offering.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph b

-Subparagraph 7

-Article 11

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

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Pro forma diluted earnings per share, which is commonly presented in initial public offerings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph b

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The weighted average number of shares or units and dilutive common stock or unit equivalents outstanding in the calculation of proforma diluted earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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No definition available.

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The weighted average number of shares (units) outstanding in the calculation of pro forma basic earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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No definition available.

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Subsequent Events Subsequent Events (Details 2) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended			0 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jan. 31, 2014 Subsequent Event CPA: 16 Merger	Dec. 31, 2013 Subsequent Event CPA: 16 Merger	Dec. 31, 2013 Pro Forma Subsequent Event CPA: 16 Merger
Pro Forma Financial Information
Pro forma total revenue		$ 512,822	$ 528,257		$ 787,219
Pro forma income attributable to W. P. Carey		138,157	116,746		85,827
Pro forma earnings per share
Basic ( in dollar per share)		$ 2.00	$ 1.69		$ 0.86
Diluted ( in dollar per share)		$ 1.98	$ 1.68		$ 0.85
Pro forma weighted average shares
Basic		68,382,378	67,990,118		99,420,924
Diluted		69,071,391	68,268,738		100,437,886
Merger and acquisition expense	$ 9,230	$ 31,639	$ 33		$ 5,000	$ 36,300
Shares issued as compensation, shares				30,729,878