Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net Income	$ 246,069us-gaap_ProfitLoss	$ 132,165us-gaap_ProfitLoss	$ 62,779us-gaap_ProfitLoss
Other Comprehensive (Loss) Income
Foreign currency translation adjustments	(117,938)	21,835	7,809
Realized and unrealized gain (loss) on derivative instruments	21,085	20	(2,262)
Change in unrealized loss on marketable securities	(10)	0	(7)
Net current period other comprehensive income (loss)	(96,863)	21,855	5,540
Comprehensive Income	149,206	154,020	68,319
Amounts Attributable to Noncontrolling Interests
Net income attributable to noncontrolling interests	(6,385)	(32,936)	(607)
Foreign currency translation adjustments	5,977	(1,883)	(1,676)
Comprehensive income attributable to noncontrolling interests	(408)	(34,819)	(2,283)
Amounts Attributable to Redeemable Noncontrolling Interest
Net loss (income) attributable to redeemable noncontrolling interest	142	(353)	(40)
Foreign currency translation adjustments	(9)	13	(6)
Comprehensive loss (income) attributable to redeemable noncontrolling interest	133	(340)	(46)
Comprehensive Income Attributable to W. P. Carey	$ 148,931us-gaap_ComprehensiveIncomeNetOfTax	$ 118,861us-gaap_ComprehensiveIncomeNetOfTax	$ 65,990us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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