Mergers and Acquisitions (Details) (USD $)	3 Months Ended			6 Months Ended						0 Months Ended	3 Months Ended						6 Months Ended		6 Months Ended				0 Months Ended		3 Months Ended					0 Months Ended		3 Months Ended		0 Months Ended	3 Months Ended
	Jun. 30, 2013 property		Jun. 30, 2012 property	Jun. 30, 2013 property		Jun. 30, 2012 property	Sep. 30, 2013	Feb. 28, 2013	Dec. 31, 2012	Feb. 28, 2013 ARCT III Merger [Member]	Sep. 30, 2013 ARCT IV / ARCP Merger [Member]	Feb. 28, 2013 Line of Credit [Member] Revolving Credit Facility [Member]	Jun. 30, 2013 Common Stock [Member]	Feb. 28, 2013 Furniture and Fixtures [Member] ARCT III Merger [Member]	Feb. 28, 2013 Other Assets [Member] ARCT III Merger [Member]	Sep. 30, 2013 Other Assets [Member] ARCT IV / ARCP Merger [Member]	Jun. 30, 2013 GE Capital Portfolio [Member] property	Jun. 27, 2013 GE Capital Portfolio [Member]	Jun. 30, 2013 GE Capital Portfolio [Member] Property Subject to Operating Lease [Member] property	Jun. 30, 2013 GE Capital Portfolio [Member] Direct Financing Lease [Member] property	Sep. 30, 2013 ARCT IV Exchange Ratio plus Cash [Member] Maximum [Member]	Feb. 28, 2013 Common Stock [Member] Option One [Member] ARCP Merger [Member]	Feb. 28, 2013 Cash [Member] Option Two [Member] ARCP Merger [Member]	Feb. 28, 2013 Cash [Member] Option Two [Member] ARCP shares converted from ARCT III shares [Member]	Sep. 30, 2013 Cash [Member] Option Two [Member] ARCT IV / ARCP Merger [Member]	Sep. 30, 2013 Cash [Member] Preferred Stock [Member] CapLease [Member]	Sep. 30, 2013 Cash [Member] OP Units [Member] CapLease [Member]	Sep. 30, 2013 Cash [Member] Common Stock [Member] CapLease [Member]	Sep. 30, 2013 Cash [Member] Restricted Stock [Member] CapLease [Member]	Feb. 28, 2013 ARCP [Member] ARCP Merger [Member]	Feb. 28, 2013 ARCP [Member] ARCT III Merger [Member]	Sep. 30, 2013 ARCP [Member] ARCT IV / ARCP Merger [Member]	Feb. 28, 2013 ARCP [Member] Maximum [Member] ARCT III Merger [Member]	Feb. 28, 2013 American Realty Capital III Special Limited Partnership, LLC [Member] Post-Conversion [Member] Common Stock [Member] Entity Wholly Owned by Sponsor [Member] ARCP Merger [Member]	Sep. 30, 2013 American Realty Capital III Special Limited Partnership, LLC [Member] Post-Conversion [Member] Common Stock [Member] Entity Wholly Owned by Sponsor [Member] ARCT IV / ARCP Merger [Member]	Sep. 30, 2013 Selling Commission [Member] ARCT IV / ARCP Merger [Member]
Business Acquisition [Line Items]
Convertible stock issued during period, shares																														0.95		2.05
Convertible stock issued during period, value																							$ 12.00		$ 30.00	$ 25.00	$ 8.50	$ 8.50	$ 8.50
Shares, Outstanding																						148,113,788.5	29,200,000	27,700,000
Percentage of shares outstanding																							16.50%
Common stock, issued	184,893,886			184,893,886					179,167,112				32,035,064									140,700,000
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest, Issuance of Units																																		7,300,000
Asset Management Fee Percentage, Option 1																															0.50%
Asset Management Fee Percentage, Option 2										0.40%
Unadjusted Book Value of Assets																																	$ 3,000,000,000
Furniture and Fixtures, Gross														4,100,000
Merger Expenses Agreed To															1,700,000	5,800,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment								1,000,000
Debt to be Extinguished Upon Consummation of Merger												150,000,000
Number of Properties Acquired	433	[1]	116	481	[1]	170											447		400	47
Real Estate Investment, Aggregate Purchase Price																		773,971,451.000
Consideration Paid in Cash, percent											25.00%
Share Price																					$ 14.94
ARCT IV Common Stock Floor for stock consideration, price							30.62
Related Party Transaction, Real Estate Selling Commissions, Percentage																																				2.00%
Related Party Transaction, Amounts of Transaction																																				8,400,000
ARCT IV Implied price of common stock, amount							30.47
Consideration Paid in Stock, percent											75.00%
Subordinated Distributions of Net Sale Proceeds																																			$ 65,200,000

[1] Excludes 47 properties comprised of $67.5 million of net investments subject to direct financing leases