SELF STORAGE PROPERTIES (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | 12 Months Ended | |
|---|---|---|---|---|
Mar. 31, 2013 |
Dec. 31, 2013 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Real Estate Properties [Line Items] | ||||
| Land | $ 315,867 | $ 236,691 | ||
| Buildings and improvements | 829,093 | 600,284 | ||
| Furniture and equipment | 2,241 | 1,966 | ||
| Total self storage properties | 1,147,201 | 838,941 | ||
| Less accumulated depreciation | (68,100) | (39,614) | ||
| Self storage properties, net | 1,079,101 | 799,327 | ||
| Depreciation expense related to self storage properties | $ 5,800 | $ 28,500 | $ 15,500 | |
| NSA Predecessor [Member] | ||||
| Real Estate Properties [Line Items] | ||||
| Depreciation expense related to self storage properties | $ 1,000 | |||