UNAUDITED SELECTED QUARTERLY FINANCIAL DATA (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Quarterly Financial Information Disclosure [Abstract] | |||||||||||
| Total revenues | $ 89,298 | $ 85,382 | $ 79,723 | $ 76,493 | $ 73,368 | $ 68,858 | $ 64,341 | $ 61,563 | $ 330,896 | $ 268,130 | $ 199,046 |
| Total operating expenses | 60,440 | 57,869 | 56,033 | 54,900 | 51,448 | 47,561 | 45,008 | 45,613 | 229,242 | 189,630 | 141,390 |
| Income from operations | 28,858 | 27,513 | 23,690 | 21,593 | 21,920 | 21,297 | 19,333 | 15,950 | 101,654 | 78,500 | 57,656 |
| Gain (loss) on sale of self storage properties | 0 | 0 | (83) | 474 | (28) | 106 | 5,637 | 0 | 391 | 5,715 | 0 |
| Net income | 14,483 | 16,829 | 13,041 | 11,973 | 12,015 | 11,226 | 15,576 | 7,181 | 56,326 | 45,998 | 24,866 |
| Net income (loss) attributable to common shareholders | $ (9,223) | $ 1,806 | $ 3,304 | $ 7,872 | $ (3,532) | $ 1,271 | $ 2,367 | $ 555 | $ 3,759 | $ 661 | $ 17,965 |
| Earnings (loss) per share - basic (in dollars per share) | $ (0.16) | $ 0.03 | $ 0.07 | $ 0.16 | $ (0.08) | $ 0.03 | $ 0.05 | $ 0.01 | $ 0.07 | $ 0.01 | $ 0.60 |
| Earnings (loss) per share - diluted (in dollars per share) | $ (0.16) | $ 0.03 | $ 0.07 | $ 0.09 | $ (0.08) | $ 0.03 | $ 0.05 | $ 0.01 | $ 0.07 | $ 0.01 | $ 0.31 |
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. No definition available.
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- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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