Acquisitions of CapLease, Cole and CCPT - Cole Credit Property Trust Acquisition (Details) (Cole Credit Property Trust, Inc. [Member], USD $)	0 Months Ended	12 Months Ended
	May 19, 2014	Dec. 31, 2014	May 19, 2014
Cole Credit Property Trust, Inc. [Member]
Business Acquisition [Line Items]
Purchase price	$ 73,200,000
Land	28,258,000		28,258,000
Buildings, fixtures and improvements	113,296,000		113,296,000
Acquired intangible lease assets	17,960,000		17,960,000
Total real estate investments	159,514,000		159,514,000
Cash and cash equivalents	167,000		167,000
Restricted cash	2,420,000		2,420,000
Prepaid expenses and other assets	297,000		297,000
Total identifiable assets acquired	162,398,000		162,398,000
Mortgage notes payable, net	85,286,000		85,286,000
Unsecured credit facility	800,000		800,000
Accounts payable and accrued expenses	443,000		443,000
Below-market lease liabilities	1,752,000		1,752,000
Due to affiliates	568,000		568,000
Deferred rent and other liabilities	390,000		390,000
Total liabilities assumed	89,239,000		89,239,000
Net identifiable assets acquired	73,159,000		73,159,000
Revenue of acquiree since acquisition date		8,200,000
Earnings or loss of acquiree since acquisition date		$ 1,800,000