Segment Reporting - Total Company (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information Profit Loss
Revenues	$ 201,143	$ 221,528	$ 402,953	$ 440,587
Operating expenses	109,202	127,991	230,168	262,873
Other income and (expenses)	(18,167)	(27,423)	(43,679)	(53,090)
Provision for income taxes	(6,262)	(2,448)	(260)	(1,143)
Gain on sale of real estate, net of tax	11,912	3,465	18,644	3,475
Net income attributable to noncontrolling interests	(3,743)	(2,813)	(6,535)	(5,154)
Net Income Attributable to W. P. Carey	$ 75,681	$ 64,318	$ 140,955	$ 121,802