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Represents the number of real estate properties that were acquired.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect per basic share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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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.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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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.

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PRO FORMA FINANCIAL INFORMATION (Details) $ / shares in Units, $ in Thousands	3 Months Ended			21 Months Ended
	Mar. 31, 2017 USD ($) $ / shares	Dec. 31, 2016 USD ($) property	Mar. 31, 2016 USD ($) $ / shares	Sep. 30, 2016 property
Consolidated results of operations on a pro forma basis
Pro forma revenue \| $	$ 133,037		$ 123,799
Pro forma income \| $	$ 29,279		$ 24,032
Earnings per share from continuing operations:
Basic - as reported (in dollars per share)	$ 0.14		$ 0.08
Diluted - as reported (in dollars per share)	0.14		0.08
Basic - as pro forma (in dollars per share)	0.16		0.13
Diluted - as pro forma (in dollars per share)	$ 0.16		$ 0.13
Self-storage facilities
Self-storage facilities
Number of self-storage facilities acquired \| property		28		28
Aggregate purchase price \| $		$ 403,600