Merger with CPA 15 (Details 2) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Pro Forma Financial Information
Pro forma total revenue	$ 512,822	$ 528,257
Pro forma income attributable to W. P. Carey	$ 138,157	$ 116,746
Pro forma earnings per share
Basic ( in dollar per share)	$ 2.00	$ 1.69
Diluted ( in dollar per share)	$ 1.98	$ 1.68
Pro forma weighted average shares
Basic	68,382,378	67,990,118
Diluted	69,071,391	68,268,738

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.

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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

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-Name Accounting Standards Codification

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

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