Organization and Offering (Narratives) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2014 property tenant sqft	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of real estate properties	358
Number of tenants	108
Square footage of real estate properties	34,000,000
Real Estate Properties
Number of operating properties	75
Square footage of operating properties	6,000,000
Capital interest in operating partnership	99.99%
Public Offerings
Proceeds from issuance of shares, value		$ 96,853
Proceeds from issuance DRIP follow-on public offering	$ 50,194
Self storage
Real Estate Properties
Number of operating properties	71