Indebtedness Secured Debt (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Debt Instrument [Line Items]
Repayments of Secured Debt	$ 5,708	$ 46,123
Fixed Rate Secured Debt [Member]
Debt Instrument [Line Items]
Repayments of Secured Debt	$ 3,200
Debt Instrument, Interest Rate, Stated Percentage	7.43%
Minimum [Member] \| Fixed Rate Secured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	3.90%
Maximum [Member] \| Fixed Rate Secured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	4.20%

Repaid Debt, Weighted Average Interest Rate

No definition available.

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Namespace Prefix:	dre_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

+ Details

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

- Details

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- Details

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Namespace Prefix:
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- Details

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