SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands |
Jun. 30, 2018
USD ($)
partnership
property
|
Dec. 31, 2017
USD ($)
property
|
|---|---|---|
| Variable Interest Entity [Line Items] | ||
| Number of self storage properties | property | 551 | |
| Net book value of real estate owned | $ 2,268,390 | $ 2,104,875 |
| Carrying value of fixed rate mortgages | 1,148,460 | $ 954,991 |
| Number of properties held for sale | property | 1 | |
| Mortgages | Fixed Rate Mortgages | ||
| Variable Interest Entity [Line Items] | ||
| Carrying value of fixed rate mortgages | $ 273,335 | $ 271,491 |
| VIE, Primary Beneficiary | ||
| Variable Interest Entity [Line Items] | ||
| Number of partnerships considered to be VIEs | partnership | 21 | |
| Number of self storage properties | property | 34 | |
| Net book value of real estate owned | $ 244,100 | 248,000 |
| VIE, Primary Beneficiary | Mortgages | Fixed Rate Mortgages | ||
| Variable Interest Entity [Line Items] | ||
| Carrying value of fixed rate mortgages | $ 139,400 | $ 140,300 |
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- Definition Debt, Long-term and Short-term, Combined Amounts, Gross No definition available.
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- Definition Number Of Partnerships Considered Variable Interest Entities No definition available.
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- Definition Number Of Properties Held For Sale No definition available.
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- Definition The number of real estate properties owned as of the balance sheet date. No definition available.
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- Definition Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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