Merger with CPA:16 and CPA:15 (Details 2) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pro Forma Financial Information
Pro forma total revenue	$ 931,309	$ 780,578	$ 512,822,000
Pro forma net income from continuing operations, net of tax	139,698	146,525
Pro forma net income attributable to noncontrolling interests	(5,380)	10,963
Pro forma net loss (income) attributable to redeemable noncontrolling interest	142	(1,909)
Pro forma net income from continuing operations, net of tax attributable to W. P. Carey	$ 134,460	$ 155,579	$ 138,157,000
Pro forma earnings per share
Basic ( in dollar per share)	$ 1.32us-gaap_BasicEarningsPerShareProForma	$ 1.56us-gaap_BasicEarningsPerShareProForma	$ 2.00us-gaap_BasicEarningsPerShareProForma
Diluted ( in dollar per share)	$ 1.31us-gaap_DilutedEarningsPerShareProForma	$ 1.54us-gaap_DilutedEarningsPerShareProForma	$ 1.98us-gaap_DilutedEarningsPerShareProForma
Pro forma weighted average shares
Basic	101,296,847	99,420,924	68,382,378
Diluted	102,360,038	100,437,886	69,071,391

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

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-Name Accounting Standards Codification

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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

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