Other Noncontrolling Interests - Additional Information (Detail)	Jun. 11, 2015 USD ($) property	Jun. 30, 2016 joint_venture
Noncontrolling Interest [Line Items]
Purchase of capital interest by entity in a joint venture partner of a consolidated property	1.00%
Cash paid for acquiring interest in a joint venture partner of a consolidated property	$ 1,267,000
Number of operating stores owned by consolidated joint venture \| property	19
Carrying amount of noncontrolling interest	$ 0
Other [Member]
Noncontrolling Interest [Line Items]
Number of consolidated joint ventures \| joint_venture		2
Other [Member] \| Minimum [Member]
Noncontrolling Interest [Line Items]
Voting interests of third-party owners		17.50%
Other [Member] \| Maximum [Member]
Noncontrolling Interest [Line Items]
Voting interests of third-party owners		20.00%

Increase In Ownership Percentage By Parent In Joint Venture Partner In Consolidated Self Storage Property

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Noncontrolling interest carrying amount.

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- Definition

Represents the number of properties owned by the joint venture.

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- Definition

The cash outflow associated with the purchase of interest in a joint venture partner of a consolidated property.

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No definition available.

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Represents the number of consolidated joint ventures as of the balance sheet date.

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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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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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