v2.4.0.8

Real Estate - Summary of Dispositions (Detail) (USD $) In Thousands, unless otherwise specified		9 Months Ended
	Jun. 30, 2014 sqft	Sep. 30, 2014 Continuing Operations [Member] Contributions to Co-investment Ventures [Member] Property sqft	Sep. 30, 2013 Continuing Operations [Member] Contributions to Co-investment Ventures [Member] sqft Property	Sep. 30, 2014 Continuing Operations [Member] Dispositions to Third Parties [Member] Property sqft	Sep. 30, 2013 Continuing Operations [Member] Dispositions to Third Parties [Member] Property sqft	Sep. 30, 2014 Discontinued Operations [Member] sqft Property	Sep. 30, 2013 Discontinued Operations [Member] Property sqft
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties		115	221	106			39
Square feet	12,600,000	22,806,000	62,213,000	14,663,000			4,802,000
Net proceeds		$ 1,627,424	$ 5,205,322	$ 955,240	$ 84,518		$ 297,465
Net gains on contributions and dispositions		156,746	407,788	180,949	2,280
Net gains from dispositions, including taxes							$ 59,598

X

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

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Balance Type:	na
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X

- Definition

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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Balance Type:	credit
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X

- Definition

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.14(d))

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 14

-Subparagraph d

-Article 9

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- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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Balance Type:	debit
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