SELF STORAGE PROPERTY ACQUISITIONS AND DISPOSITIONS - Acquisitions (Details) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2018
USD ($)
property
|
Sep. 30, 2018
USD ($)
property
|
Jun. 30, 2018
USD ($)
property
|
Mar. 31, 2018
USD ($)
property
|
Dec. 31, 2017
USD ($)
property
|
Sep. 30, 2017
USD ($)
property
|
Jun. 30, 2017
USD ($)
property
|
Mar. 31, 2017
USD ($)
property
|
Dec. 31, 2018
USD ($)
property
|
Dec. 31, 2017
USD ($)
property
|
Dec. 31, 2016
USD ($)
|
|
| Business Acquisition [Line Items] | |||||||||||
| Cash and Acquisition Costs | $ 0 | $ 0 | $ 19,933 | ||||||||
| 2018 Acquisitions [Member] | |||||||||||
| Business Acquisition [Line Items] | |||||||||||
| Number of self storage properties acquired | property | 7 | 13 | 12 | 25 | 57 | ||||||
| Cash and Acquisition Costs | $ 49,221 | $ 102,012 | $ 62,470 | $ 105,135 | $ 318,838 | ||||||
| Value of OP Equity | 2,000 | 3,660 | 0 | 22,403 | 28,063 | ||||||
| Mortgages Assumed | 0 | 0 | 0 | 7,581 | 7,581 | ||||||
| Other Liabilities | 174 | 856 | 467 | 670 | 2,167 | ||||||
| Total consideration given and liabilities assumed | $ 51,395 | $ 106,528 | $ 62,937 | $ 135,789 | $ 356,649 | ||||||
| 2017 Acquisitions [Member] | |||||||||||
| Business Acquisition [Line Items] | |||||||||||
| Number of self storage properties acquired | property | 31 | 19 | 10 | 5 | 65 | ||||||
| Cash and Acquisition Costs | $ 181,809 | $ 122,742 | $ 60,672 | $ 26,780 | $ 392,003 | ||||||
| Value of OP Equity | 17,019 | 267 | 8,931 | 4,964 | 31,181 | ||||||
| Mortgages Assumed | 0 | 0 | 0 | 0 | 0 | ||||||
| Other Liabilities | 2,220 | 826 | 387 | 183 | 3,616 | ||||||
| Total consideration given and liabilities assumed | $ 201,048 | $ 123,835 | $ 69,990 | $ 31,927 | $ 426,800 | ||||||