Acquisitions and Dispositions (Narrative) (Details) (USD $)	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012
Gain on Step Acquisition	$ (962,000)	$ 0
Proceeds from land and depreciated property sales, net	259,169,000	89,450,000
Capital distributions from unconsolidated companies	89,237,000	0
Gains on Depreciated Property Sales Share of Joint Venture	48,800,000
Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Gain on Step Acquisition	962,000
Business Combination, Acquisition Related Costs	$ (2,700,000)
Number of real estate properties acquired	13
Weighted average remaining life of property (years)	7 years 7 months
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	2
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 Pennsylvania [Member] \| Industrial [Member] \| Other Two Thousand Thirteen Acquisitions [Member] [Domain] [Member]
Number of real estate properties acquired	1
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

Earnings from Depreciated Property Sales Share of Joint Venture

No definition available.

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Namespace Prefix:	dre_
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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
Balance Type:	na
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_
Data Type:	xbrli:durationItemType
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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Namespace Prefix:	us-gaap_
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
Balance Type:	credit
Period Type:	duration

- Definition

Cash inflow received as distributions, returns of capital, or sale proceeds from partnership interests held for investment purposes.

+ References

No definition available.

+ Details

Name:	us-gaap_ProceedsFromLimitedPartnershipInvestments
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