American Realty Capital Trust (Details) (ARCT, USD $)	12 Months Ended
	Dec. 31, 2012 item	Jan. 22, 2013 property
ARCT
Acquisition of American Realty Capital Trust, Inc.
Cash paid for common stock on acquisition (in dollars per share)		$ 0.35
Common stock conversion ratio		0.2874
Repayment of amount outstanding under ARCT's revolving credit facility and term loan		$ 552,900,000
Number of properties added to portfolio		515
Closing price of common stock (in dollars per share)		$ 44.04
Preliminary purchase price of the ARCT acquisition
Consideration associated with equity issued		2,027,753,000
Cash consideration paid to previous owners of ARCT		59,142,000
Total preliminary purchase consideration		2,086,895,000
Assets:
Total real estate and related intangible assets		3,178,862,000
Cash and cash equivalents, accounts receivable, and other assets, net		45,667,000
Total Assets		3,224,529,000
Liabilities:
Lines of credit payable		317,207,000
Term loan		235,000,000
Mortgage notes payable		538,888,000
Accounts payable, accrued expenses, and other liabilities, net		32,577,000
Total Liabilities		1,123,672,000
Non-controlling interest		13,962,000
Estimated fair value of net assets acquired		2,086,895,000
Transaction Costs
Estimated total merger-related transaction costs	19,000,000
Total merger-related transaction costs	7,900,000
Contingent payments	$ 6,000,000
Litigation
Number of alleged class action lawsuits filed in Maryland	6
Number of alleged class action lawsuits filed in New York	2