CONSOLIDATED STATEMENTS OF EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Cumulative-effect adjustment for the adoption of new accounting pronouncement	Total W.P. Carey Stockholders	Total W.P. Carey Stockholders Cumulative-effect adjustment for the adoption of new accounting pronouncement	$0.001 Par Value Common Stock	Additional Paid-in Capital	Distributions in Excess of Accumulated Earnings	Distributions in Excess of Accumulated Earnings Cumulative-effect adjustment for the adoption of new accounting pronouncement	Deferred Compensation Obligation	Accumulated Other Comprehensive Loss	Noncontrolling interests
Beginning equity balance at Dec. 31, 2018	$ 6,830,055		$ 6,824,278		$ 165	$ 8,187,335	$ (1,143,992)		$ 35,766	$ (254,996)	$ 5,777
Beginning equity balance, shares at Dec. 31, 2018					165,279,642
W.P. Carey Stockholders
Shares issued under ATM Program, net	391,904		391,904		$ 5	391,899
Shares issued under ATM Program, net, shares					5,169,840
Shares issued upon delivery of vested restricted share awards	(15,742)		(15,742)		$ 1	(15,743)
Shares issued upon delivery of vested restricted share awards, shares					305,508
Shares issued upon purchases under employee share purchase plan	113		113			113
Shares issued upon purchases under employee share purchase plan, value, shares					1,517
Amortization of stock-based compensation expense	9,101		9,101			9,101
Delivery of deferred vested shares, net						(1,445)			1,445
Contributions from noncontrolling interests	849										849
Distributions to noncontrolling interests	(622)										(622)
Dividends declared	(353,960)		(353,960)			4,985	(358,997)		52
Net Income	134,917		134,532				134,532				385
Other comprehensive income (loss):
Foreign currency translation adjustments	(4,360)		(4,360)							(4,360)
Unrealized (loss) gain on derivative instruments	(1,457)		(1,457)							(1,457)
Unrealized loss on investments	(4)		(4)							(4)
Ending equity balance at Jun. 30, 2019	6,990,794		6,984,405		$ 171	8,576,245	(1,368,457)		37,263	(260,817)	6,389
Ending equity balance, shares at Jun. 30, 2019					170,756,507
Beginning equity balance at Mar. 31, 2019	7,017,729		7,011,297		$ 170	8,483,301	(1,256,754)		37,263	(252,683)	6,432
Beginning equity balance, shares at Mar. 31, 2019					169,636,526
W.P. Carey Stockholders
Shares issued under ATM Program, net	88,073		88,073		$ 1	88,072
Shares issued under ATM Program, net, shares					1,116,217
Shares issued upon delivery of vested restricted share awards	(177)		(177)		$ 0	(177)
Shares issued upon delivery of vested restricted share awards, shares					2,247
Shares issued upon purchases under employee share purchase plan	113		113			113
Shares issued upon purchases under employee share purchase plan, value, shares					1,517
Amortization of stock-based compensation expense	4,936		4,936			4,936
Distributions to noncontrolling interests	(126)										(126)
Dividends declared	(177,741)		(177,741)				(177,741)
Net Income	66,121		66,038				66,038				83
Other comprehensive income (loss):
Foreign currency translation adjustments	(4,187)		(4,187)							(4,187)
Unrealized (loss) gain on derivative instruments	(3,406)		(3,406)							(3,406)
Unrealized loss on investments	(541)		(541)							(541)
Ending equity balance at Jun. 30, 2019	6,990,794		6,984,405		$ 171	8,576,245	(1,368,457)		37,263	(260,817)	6,389
Ending equity balance, shares at Jun. 30, 2019					170,756,507
Beginning equity balance at Dec. 31, 2019	$ 6,948,173	$ (14,812)	6,941,929	$ (14,812)	$ 172	8,717,535	(1,557,374)	$ (14,812)	37,263	(255,667)	6,244
Beginning equity balance, shares at Dec. 31, 2019	172,278,242				172,278,242
W.P. Carey Stockholders
Shares issued under forward sale agreements, net	$ 99,632		99,632		$ 2	99,630
Shares issued under forward sale agreements, net, shares					1,463,500
Shares issued upon delivery of vested restricted share awards	(5,272)		(5,272)		$ 0	(5,272)
Shares issued upon delivery of vested restricted share awards, shares					143,213
Shares issued upon purchases under employee share purchase plan	299		299			299
Shares issued upon purchases under employee share purchase plan, value, shares					5,472
Amortization of stock-based compensation expense	5,579		5,579			5,579
Delivery of deferred vested shares, net						(3,854)			3,854
Distributions to noncontrolling interests	(5,231)										(5,231)
Dividends declared	(363,008)		(363,008)			1,191	(365,096)		897
Redemption of noncontrolling interest	(9,865)										(9,865)
Net Income	181,906		171,390				171,390				10,516
Other comprehensive income (loss):
Foreign currency translation adjustments	(38,353)		(38,353)							(38,353)
Unrealized (loss) gain on derivative instruments	3,407		3,407							3,407
Unrealized loss on investments	0
Ending equity balance at Jun. 30, 2020	$ 6,802,455		6,800,791		$ 174	8,815,108	(1,765,892)		42,014	(290,613)	1,664
Ending equity balance, shares at Jun. 30, 2020	173,890,427				173,890,427
Other comprehensive income (loss):
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning equity balance at Mar. 31, 2020	$ 6,773,076		6,770,945		$ 172	8,712,244	(1,688,744)		42,291	(295,018)	2,131
Beginning equity balance, shares at Mar. 31, 2020					172,402,516
W.P. Carey Stockholders
Shares issued under forward sale agreements, net	99,632		99,632		$ 2	99,630
Shares issued under forward sale agreements, net, shares					1,463,500
Shares issued upon delivery of vested restricted share awards	(260)		(260)			(260)
Shares issued upon delivery of vested restricted share awards, shares					18,939
Shares issued upon purchases under employee share purchase plan	299		299			299
Shares issued upon purchases under employee share purchase plan, value, shares					5,472
Amortization of stock-based compensation expense	2,918		2,918			2,918
Delivery of deferred vested shares, net						277			(277)
Distributions to noncontrolling interests	(506)										(506)
Dividends declared	(182,448)		(182,448)				(182,448)
Redemption of noncontrolling interest	(9,865)		0								(9,865)
Net Income	115,204		105,300				105,300				9,904
Other comprehensive income (loss):
Foreign currency translation adjustments	13,847		13,847							13,847
Unrealized (loss) gain on derivative instruments	(9,442)		(9,442)							(9,442)
Unrealized loss on investments	0
Ending equity balance at Jun. 30, 2020	$ 6,802,455		$ 6,800,791		$ 174	$ 8,815,108	$ (1,765,892)		$ 42,014	$ (290,613)	$ 1,664
Ending equity balance, shares at Jun. 30, 2020	173,890,427				173,890,427