SUBSEQUENT EVENTS - Subordinated Performance Unit To OP Unit Conversion (Details) - shares |
12 Months Ended | |
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Jan. 01, 2018 |
Dec. 31, 2017 |
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| Subordinated performance units [Member] | ||
| Subsequent Event [Line Items] | ||
| Period prior to conversion for conversion rate metric | 1 year | |
| Percentage of CAD per unit used in conversion rate calculation | 110.00% | |
| Number of subordinated performance units converted (in units) | 997,074 | |
| Subordinated performance units [Member] | NSA OP, LP [Member] | ||
| Subsequent Event [Line Items] | ||
| Minimum conversion period | 2 years | |
| OP Units [Member] | NSA OP, LP [Member] | ||
| Subsequent Event [Line Items] | ||
| Minimum conversion period | 1 year | |
| Number of subordinated performance units converted (in units) | 11,050 | |
| Issuance of shares/units (in shares) | 992,210 | |
| Subsequent Event [Member] | OP Units [Member] | NSA OP, LP [Member] | ||
| Subsequent Event [Line Items] | ||
| Issuance of shares/units (in shares) | 2,024,170 |
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- Definition Conversion Of Stock, Percentage Of Cash Available For Distribution Per Unit Used In Conversion Rate No definition available.
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- Definition Conversion Of Stock, Period Prior To Conversion For Calculation Of Rate No definition available.
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- Definition Stockholders Equity Note, Unit Conversion, Minimum Conversion Period No definition available.
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- Definition The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. No definition available.
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