Merger with CPA®:16 – Global (Narratives) (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended		9 Months Ended		9 Months Ended									0 Months Ended			1 Months Ended	3 Months Ended	8 Months Ended	9 Months Ended	21 Months Ended		3 Months Ended		0 Months Ended			9 Months Ended	0 Months Ended			0 Months Ended					3 Months Ended			6 Months Ended
	Sep. 30, 2014 property	Sep. 30, 2013	Sep. 30, 2014 property	Sep. 30, 2013	Dec. 31, 2013	Jan. 31, 2014	Sep. 30, 2014 Jointly Owned Investments	Dec. 31, 2013 Assets held-for-sale property	Sep. 30, 2014 Level 3 Net operating income Minimum	Sep. 30, 2014 Level 3 Net operating income Maximum	Sep. 30, 2014 Level 3 Estimated residual value Minimum	Sep. 30, 2014 Level 3 Estimated residual value Maximum	Sep. 30, 2014 Level 3 Residual capitalization rates Minimum	Sep. 30, 2014 Level 3 Residual capitalization rates Maximum	Sep. 30, 2014 Level 3 Cash flows Minimum	Sep. 30, 2014 Level 3 Cash flows Maximum	Sep. 30, 2014 Additional Paid-in Capital	Sep. 30, 2014 CPA: 16 - Global	Mar. 31, 2014 CPA: 16 - Global	Jan. 31, 2014 CPA: 16 - Global investment	Jul. 31, 2013 CPA: 16 - Global	Sep. 30, 2014 CPA: 16 - Global	Sep. 30, 2014 CPA: 16 - Global	Sep. 30, 2014 CPA: 16 - Global	Sep. 30, 2014 CPA: 16 - Global	Dec. 31, 2012 CPA: 16 - Global	Mar. 31, 2014 CPA: 16 - Global Previously held equity interest	Jan. 31, 2014 CPA: 16 - Global Previously held equity interest investment	Sep. 30, 2014 CPA: 16 - Global Jointly Owned Investments	Mar. 31, 2014 CPA: 16 - Global Jointly Owned Investments	Jan. 31, 2014 CPA: 16 - Global Jointly Owned Investments investment	Sep. 30, 2014 CPA: 16 - Global Jointly Owned Investments	Jan. 31, 2014 CPA: 16 - Global Consolidated or partially leased investments property	Jan. 31, 2014 CPA: 16 - Global Consolidated or partially leased investments Fixed interest rate loan	Jan. 31, 2014 CPA: 16 - Global Consolidated or partially leased investments Variable interest rate loan	Jan. 31, 2014 CPA: 16 - Global Equity method investments property investment	Jan. 31, 2014 CPA: 16 - Global Equity method investments Fixed interest rate loan	Jan. 31, 2014 CPA: 16 - Global Equity method investments Variable interest rate loan	Sep. 30, 2014 CPA: 16 - Global Assets held-for-sale property	Jan. 31, 2014 CPA: 16 - Global Premium on Stock Price	Mar. 31, 2014 CPA: 16 - Global Additional Paid-in Capital	Sep. 30, 2014 Hotel property	Jan. 31, 2014 Hotel CPA: 16 - Global Consolidated or partially leased investments property	Sep. 30, 2014 Measurement period adjustment CPA: 16 - Global	Jun. 30, 2014 Measurement period adjustment CPA: 16 - Global
Merger Disclosure
Share per share exchange rate																				0.1830
Per share exchange rate																					$ 11.25
Per share closing price						$ 59.08
Merger consideration																		$ 1,816,859,000	$ 1,816,859,000	$ 1,800,000,000
Cash consideration			1,338,000	0														1,338,000	1,338,000	1,338,000
Shares issued as compensation, shares																				30,729,878
Fair value of W.P.Carey shares of common stock issued																		1,815,521,000	1,815,521,000	1,815,521,000		1,815,521,000	1,815,521,000	1,815,521,000	1,815,521,000
Shares of acquired entity received																				168,041,772
Number of real estate properties	688		688					9																									325			140						2	2
Number of properties sold																																							10
Number of investments consolidated after merger																																				5
Weighted average lease term																																	10 years 4 months 24 days			8 years 7 months 6 days
Triple-net lease, current minimum base rent receivable																																	300,100,000			63,900,000
Mortgage loans on real estate, interest rate																																	5.60%			4.80%
Lease revenues	149,243,000	75,702,000	420,563,000	222,145,000																		68,300,000	184,300,000
Income from operations	27,821,000	21,272,000	181,722,000	81,571,000																		27,300,000	62,500,000
Income attributable to noncontrolling interest																						400,000	2,200,000
Merger and acquisition expense	618,000	3,630,000	31,369,000	6,879,000	5,000,000																			30,400,000	10,600,000
Total Consideration																		2,059,840,000	2,057,914,000	2,059,840,000																								1,926,000
Total identifiable net assets																		1,810,597,000	1,808,287,000			1,810,597,000	1,810,597,000	1,810,597,000	1,810,597,000																			2,310,000
Amounts attributable to noncontrolling interests																		99,633,000	99,345,000	99,633,000		99,633,000	99,633,000	99,633,000	99,633,000																			288,000
Goodwill	702,791,000		702,791,000		350,208,000													348,876,000	348,972,000	348,876,000		348,876,000	348,876,000	348,876,000	348,876,000															428,500,000				(96,000)
Increase in market value of stock price, per share																					$ 2.55
Net asset value, per share																										$ 8.70
Gain on change in control of interests	0	0	104,645,000	0																							73,100,000					30,200,000
Recognition of deferred revenue as a result of the CPA®:16 Merger			4,848,000	0
Carrying value of equity investment in CPA pre merger																				274,100,000											142,500,000
Number of shares owned																				38,229,294
Valuation techniques			•Discount rates applied to the estimated net operating income of each property ranged from approximately 4.75% to 15.25%;•Discount rates applied to the estimated residual value of each property ranged from approximately 4.75% to 14.00%;•Residual capitalization rates applied to the properties ranged from approximately 5.00% to 12.50%;•The fair market value of the property level debt was determined based upon available market data for comparable liabilities and by applying selected discount rates to the stream of future debt payments; and•Discount rates applied to the property level debt cash flows ranged from approximately 1.80% to 8.75%.
Discount rate							5.00%		4.75%	15.25%	4.75%	14.00%	5.00%	12.50%	1.80%	8.75%
Senior unsecured credit facility and unsecured term loan	618,945,000		618,945,000		575,000,000															170,000,000
Loans outstanding, count																																		92	18		17	5
Non-recourse debt	2,702,133,000		2,702,133,000		1,492,410,000													1,768,288,000	1,768,288,000	1,768,288,000		1,768,288,000	1,768,288,000	1,768,288,000	1,768,288,000											300,000,000
Number of unconsolidated investments																				18
Number of consolidated investments																																				11
Number of jointly owned investments with affiliate																												12			9					2
Purchase on remaining interest			280,936,000														41,374,000																								42,000,000
Carrying value of noncontrolling interest acquired from entity																												236,800,000
Fair value of noncontrolling interests acquired																		(278,187,000)	(278,829,000)	(278,187,000)		(278,187,000)	(278,187,000)	(278,187,000)	(278,187,000)																			642,000	(600,000)
Fair value of W. P. Carey & Co. LLC equity interest in jointly-owned investments with CPA:16 prior to the CPA:16 Merger																		$ 348,448,000	$ 347,164,000	$ 348,448,000									$ 172,720,000	$ 172,720,000	$ 172,720,000													$ 1,284,000