Represents the amount of accretion liability arised during the period.

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Represents the cash contributed by noncontrolling owners to the joint venture.

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Represents the properties contributed by the entity to the joint venture.

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Represents the amount of loan commitment which are secured by a mortgage on the real estate assets.

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No definition available.

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Represents information pertaining to the number of parcels into which the subdivision of land is done reporting period.

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No definition available.

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Represents information pertaining to the number of parcels of land sold during the reporting period.

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No definition available.

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Represents the number of self-storage facilities owned and operated.

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Represents the number of real estate properties that were sold.

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No definition available.

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- Definition

Represents the option to call ownership interest of another member.

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No definition available.

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Represents the option to put ownership interest in the venture.

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No definition available.

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Represents the period of option to call ownership interest of another member.

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No definition available.

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Represents the period of option to put ownership interest in venture.

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Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

-Paragraph 1

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-Topic 420

-SubTopic 10

-Section 35

-Paragraph 4

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

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-Paragraph 2

-Subparagraph (c)

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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-Topic 230

-SubTopic 10

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-Paragraph 28

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 23

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-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4616395-111683

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

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Total carrying amount of mortgage loans as of the balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

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-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

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-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29.6)

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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No definition available.

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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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The cash outflow associated with the purchase of real estate held for investment purposes.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

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-Name Accounting Standards Codification

-Topic 230

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-Paragraph 14

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Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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-Name Accounting Standards Codification

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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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-Name Accounting Standards Codification

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NONCONTROLLING INTERESTS (Details)	12 Months Ended					0 Months Ended	1 Months Ended	12 Months Ended				0 Months Ended				12 Months Ended
NONCONTROLLING INTERESTS (Details)	Dec. 31, 2014 USD ($) property	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2014 Tilloston Ave Member USD ($)	Dec. 31, 2014 Jamaica Ave Member USD ($)	Jun. 30, 2014 USIFB, LLP	Jun. 30, 2014 USIFB, LLP USD ($) facility	Dec. 31, 2014 USIFB, LLP USD ($)	Dec. 31, 2008 USIFB, LLP property	Dec. 31, 2013 USIFB, LLP USD ($)	Dec. 31, 2013 USIFB, LLP GBP (£)	Aug. 13, 2012 HART USD ($)	Aug. 13, 2009 HART USD ($) property	Aug. 13, 2012 HART	Aug. 13, 2009 HART	Dec. 31, 2014 SRLLC USD ($) item	Dec. 31, 2013 SRLLC USD ($)	Dec. 31, 2014 SNL USD ($) property	Dec. 31, 2014 Tilloston Ave USD ($)	Dec. 31, 2014 Tilloston Ave Tilloston Ave Member USD ($)	Dec. 31, 2014 Jamaica Ave USD ($)	Dec. 31, 2014 Jamaica Ave Jamaica Ave Member USD ($)
Interests in Consolidated Real Estate Joint Ventures
Option to put ownership interest in the venture																				$ 17,000,000		$ 12,500,000
Period of option to call ownership interest of another member																			1 year		1 year
Period of option to put ownership interest in venture																				1 year		1 year
Option to call ownership interest of another member																			17,000,000		12,500,000
Accretion liability				17,000,000	12,500,000
Accrued accretion expenses	(1,685,000)us-gaap_AccretionExpense	(1,018,000)us-gaap_AccretionExpense	(707,000)us-gaap_AccretionExpense	2,400,000	6,600,000
Ownership interest held by the entity (as a percent)						97.00%		97.00%	97.00%			100.00%				90.00%		90.00%	51.00%		51.00%
Number of self-storage facilities owned and operated									2				22					2
Total assets								5,700,000								14,700,000		12,300,000	2,900,000		15,200,000
Total liabilities								200,000								10,600,000		2,300,000	2,800,000		7,300,000
Carrying amount of mortgage loans										6,800,000	4,100,000					9,600,000		1,200,000
Amount of mortgage loan commitment																14,600,000		20,100,000
Gain (loss) from sale of land	475,000us-gaap_GainLossOnSaleOfProperties															0
Payments to acquire land for development																	13,100,000
Number of parcels in which the subdivision of land is done reporting period																2
Number of parcel sold																1
Number of assets sold	1cube_NumberOfRealEstatePropertiesSold						1
Proceeds from sales of facilities, net	13,475,000	123,780,000	52,630,000				7,000,000									6,500,000
Cash contributed by Heitman, LLC													51,000,000
Properties contributed by the entity													102,000,000
Cash distribution received from joint venture													51,000,000
Minority ownership interest (as a percent)															50.00%				49.00%		49.00%
Percentage of interest acquired in HART														50.00%
Purchase price paid for ownership interest in joint venture												61,100,000
Elimination of noncontrolling interest in subsidiaries due to acquisition			56,984,000									38,700,000
Reduction to additional paid in capital	$ 642,000	$ 831,000										$ 18,500,000