Quarterly report pursuant to Section 13 or 15(d)

SUBSEQUENT EVENTS (Details)

v3.3.0.814
SUBSEQUENT EVENTS (Details)
$ in Thousands
 1 Months Ended 3 Months Ended 9 Months Ended
Jan. 01, 2015
property
Oct. 31, 2015
USD ($)
property
shares
Sep. 30, 2015
USD ($)
property
Jun. 30, 2015
USD ($)
property
Mar. 31, 2015
USD ($)
property
Sep. 30, 2015
USD ($)
property
Sep. 30, 2014
USD ($)
Subsequent Event [Line Items]              
Number of self storage properties acquired | property 5   15 21 6 42  
Aggregate purchase price     $ 98,239 $ 95,083 $ 34,235 $ 227,557  
Consideration given, cash           132,196 $ 165,904
Consideration given, value of vesting LTIP units     10,188 $ 22,971 8,954 42,113  
Business combination, noncontrolling interest, fair value     $ 8,300   $ 6,800 $ 8,300  
Subsequent Event [Member] | Series of Individually Immaterial Business Acquisitions [Member]              
Subsequent Event [Line Items]              
Number of self storage properties acquired | property   15          
Aggregate purchase price   $ 67,800          
Consideration given, cash   36,700          
Consideration given, value of vesting LTIP units   1,400          
Business combination, noncontrolling interest, fair value   $ 6,100          
Subsequent Event [Member] | Series of Individually Immaterial Business Acquisitions [Member] | Participating Regional Operator [Member]              
Subsequent Event [Line Items]              
Number of self storage properties acquired | property   14          
Subsequent Event [Member] | Series of Individually Immaterial Business Acquisitions [Member] | Unidentified Third Parties [Member]              
Subsequent Event [Line Items]              
Number of self storage properties acquired | property   1          
Subsequent Event [Member] | Series of Individually Immaterial Business Acquisitions [Member] | LTIP units [Member]              
Subsequent Event [Line Items]              
Share vested upon acquisition of property | shares   99,000          
Unvested LTIP units which vest upon future acquisition of properties | shares   522,900          
Subsequent Event [Member] | Series of Individually Immaterial Business Acquisitions [Member] | Mortgages [Member]              
Subsequent Event [Line Items]              
Assumption and Repayment of Debt for properties acquired   $ 23,600