CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Comprehensive Income [Abstract]
Net Income	$ 78,729	$ 23,721	$ 102,345	$ 38,023
Other Comprehensive Income (Loss):
Foreign currency translation adjustments	1,945	(4,627)	7,671	(8,034)
Unrealized loss on derivative instrument	(1,061)	(735)	(239)	(1,295)
Change in unrealized appreciation on marketable securities	(2)	(7)	(3)	(11)
Change in other comprehensive income (loss)	882	(5,369)	7,429	(9,340)
Comprehensive Income	79,611	18,352	109,774	28,683
Amounts Attributable to Noncontrolling Interests:
Add: Net loss attributable to noncontrolling interests	384	128	714	414
Foreign currency translation adjustment	(278)	26	(1,053)	145
Comprehensive loss (income) attributable to noncontrolling interests	106	154	(339)	559
Amounts Attributable to Redeemable Noncontrolling Interest:
Less: Net income attributable to redeemable noncontrolling interest	(1)	(417)	(604)	(592)
Foreign Currency Translation Adjustment	(2)	16	(9)	17
Comprehensive income attributable to redeemable noncontrolling interest	(3)	(401)	(613)	(575)
Comprehensive Income Attributable to W. P. Carey Members	$ 79,714	$ 18,105	$ 108,822	$ 28,667

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to noncontrolling interests, if any. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The portion of net income (loss) attributable to the noncontrolling interest (if any) deducted in order to derive the portion attributable to the parent.

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Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into functional currency of the reporting entity, net of tax.

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This element represents Other Comprehensive Income (Loss), Net of Tax, for the period. Includes deferred gains (losses) on qualifying hedges, unrealized holding gains (losses) on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

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Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain or loss, net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain or loss at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains or losses realized upon the sale of securities, after tax; and (3) the unrealized gains or losses realized upon the write-down of securities, after tax.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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