Merger Agreement Merger Agreement (Details) (USD $)			0 Months Ended		0 Months Ended					0 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Feb. 28, 2013 ARCT III Merger [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 ARCP [Member] ARCP Merger [Member]	Feb. 28, 2013 ARCP [Member] ARCT III Merger [Member]	Sep. 07, 2011 Line of Credit [Member] Revolving Credit Facility [Member]	Mar. 31, 2013 Common Stock [Member]	Feb. 28, 2013 Post-Conversion [Member] Common Stock [Member] Entity Wholly Owned by Sponsor [Member] American Realty Capital III Special Limited Partnership, LLC [Member] ARCP Merger [Member]	Feb. 28, 2013 Furniture and Fixtures [Member] ARCT III Merger [Member]	Feb. 28, 2013 Other Assets [Member] ARCT III Merger [Member]	Dec. 31, 2011 Maximum [Member] ARCP [Member] ARCT III Merger [Member]
Business Acquisition [Line Items]
Convertible stock issued during period, shares						0.95
Common stock, issued	154,322,183	179,167,112		140,700,000					2,131,000
Convertible stock issued during period, value					$ 12.00
Asset Management Fee Percentage, Option 1							0.50%
Unadjusted Book Value of Assets													$ 3,000,000,000
Asset Management Fee Percentage, Option 2			0.40%
Purchase Price of Furniture, Fixtures and all Other Assets			5,800,000								4,100,000	1,700,000
Debt to be Extinguished Upon Consummation of Merger								$ 150,000,000
Shares, Outstanding				148,113,788.5	29,200,000
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest, Issuance of Units										7,300,000
Percentage of shares outstanding					16.50%