Acquisitions and Dispositions (Narrative) (Details) (USD $)	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Gain on Step Acquisition	$ (962,000)	$ 0
Proceeds from land and depreciated property sales, net	330,740,000	112,559,000
Capital distributions from unconsolidated companies	106,306,000	4,890,000
Gains on Depreciated Property Sales Share of Joint Venture	49,000,000
Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Gain on Step Acquisition	962,000
Business Combination, Acquisition Related Costs	(3,500,000)
Number of real estate properties acquired	15
Weighted average remaining life of property (years)	7 years 7 months 10 days
Medical Office Properties [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	1
New Jersey [Member] [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	3
Southern California [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	3
Central California [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	2
Houston, Texas [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	1
Kansas City, Missouri [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	1
St. Louis, Missouri [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	1
Northeast or Central Pennsylvania [Member] [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	2
Indianapolis Indiana [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	1
Office [Member]
Number of Real Estate Properties Sold	17
Industrial [Member]
Number of Real Estate Properties Sold	1
Proceeds from sale of Property [Member]
Capital distributions from unconsolidated companies	$ 89,500,000

Earnings from Depreciated Property Sales Share of Joint Venture

No definition available.

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- Definition

The number of real estate properties, by acquisition, product type, or geographic location, acquired during the reporting period.

+ References

No definition available.

+ Details

Name:	dre_NumberOfRealEstatePropertiesAcquired
Namespace Prefix:	dre_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

The number of real estate properties, by sale, product type, or geographic location, sold during the reporting period.

+ References

No definition available.

+ Details

Name:	dre_NumberOfRealEstatePropertiesSold
Namespace Prefix:	dre_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e1043-128460

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(2)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration