Organization and Formation of Company (Details Textual)	Jun. 30, 2012 State Province sqft JointVentures IndustrialProperty
Organization and Formation of Company (Textual) [Abstract]
Number of industrial properties owned	734
Organization and Formation of Company (Additional Textual) [Abstract]
Ownership interest of sole general partner	94.70%
Ownership interest of limited partners	5.30%
Number of Joint Ventures	2
Number of states in which industrial properties are located	26
Number of provinces in which industrial properties are located	1
Gross Leasable Area (GLA) of industrial properties owned	65,900,000
2007 Europe Joint Venture [Member]
Organization and Formation of Company (Textual) [Abstract]
Number of industrial properties owned	0

Noncontrolling interest ownership percentage by parent .

No definition available.

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The number of joint ventures that the entity owns a non-controlling interest in as of the balance sheet date.

No definition available.

The number of provinces in Canada in which the entity operates as of the balance sheet date.

No definition available.

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Area of a real estate property.

No definition available.

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Data Type:	num:areaItemType
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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

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The number of real estate properties owned as of the balance sheet date.

No definition available.

Name:	us-gaap_NumberOfRealEstateProperties
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Data Type:	xbrli:integerItemType
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The number of states the entity operates in as of the balance sheet date.

No definition available.

Name:	us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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Period Type:	instant