Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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

- Definition

Amount of the fee for available but unused credit capacity under the credit facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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

- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the required periodic payment applied to interest.

+ References

+ Details

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

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ 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=56944662&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

Aggregate insurance limit for terrorism losses

+ References

No definition available.

+ Details

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Namespace Prefix:	wre_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Instrument, Variable Rate

+ References

No definition available.

+ Details

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

- Definition

Insurance Provider, Covered Terrorism Losses, Percent

+ References

No definition available.

+ Details

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Namespace Prefix:	wre_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Extension Term

+ References

No definition available.

+ Details

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Namespace Prefix:	wre_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Amount Outstanding [Roll Forward]

+ References

No definition available.

+ Details

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Namespace Prefix:	wre_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

U.S. Covered Terrorism Losses, Percent

+ References

No definition available.

+ Details

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Balance Type:	na
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Unsecured Lines Of Credit Payable - Repayments and Borrowings on Unsecured Lines of Credit (Details) - USD ($)		9 Months Ended	12 Months Ended
	Jun. 23, 2015	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Line of Credit Facility [Line Items]
U.S. Covered Terrorism Losses, Percent						0.85
Line of Credit Facility, Periodic Payment, Interest			$ 2,266,000	$ 196,000	$ 867,000
Line of Credit Facility, Amount Outstanding [Roll Forward]
Balance at December 31, 2014		$ 50,000,000	50,000,000	0
Balance at December 31, 2015			$ 105,000,000	50,000,000	0
Line Of Credit Extension Term			1 year
Line of Credit Facility, Commitment Fee Amount			$ 1,241,000	1,267,000	1,267,000
Total revolving credit facilities at December 31						$ 600,000,000	$ 500,000,000	$ 500,000,000
Lines of credit		50,000,000	50,000,000	0	0	$ 105,000,000	$ 50,000,000	$ 0
Weighted average daily borrowings during the year			167,573,000	12,849,000	61,548,000
Maximum daily borrowings during the year			$ 350,000,000	$ 55,000,000	$ 135,000,000
Weighted average interest rate during the year			0.00%	0.00%	0.00%
Weighted average interest rate at period end						0.00%	0.00%
Insurance Provider, Covered Terrorism Losses, Percent						0.10
Aggregate Insurance Limit For Terrorism Losses			$ 100,000,000,000
Credit Facility No. 1 [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Balance at December 31, 2014		5,000,000	5,000,000
Borrowings			3,000,000
Repayments			(8,000,000)
Balance at December 31, 2015			$ 0	$ 5,000,000
Line of Credit Facility, Expiration Date			Jun. 30, 2015
Total revolving credit facilities at December 31						$ 100,000,000
Lines of credit		5,000,000	$ 5,000,000	5,000,000		0	$ 5,000,000
Credit Facility No 2 [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Balance at December 31, 2014		45,000,000	45,000,000
Borrowings			150,000,000
Repayments			(195,000,000)
Balance at December 31, 2015			$ 0	45,000,000
Line of Credit Facility, Expiration Date			Jul. 31, 2016
Total revolving credit facilities at December 31						400,000,000
Lines of credit		$ 45,000,000	$ 45,000,000	$ 45,000,000		0	$ 45,000,000
credit facility 2015 [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Total revolving credit facilities at December 31						$ 1,000,000,000
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
LIBOR Rate						0.43%
London Interbank Offered Rate (LIBOR) [Member] \| Credit Facility No. 1 [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate			1.20%
London Interbank Offered Rate (LIBOR) [Member] \| Credit Facility No 2 [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate			1.20%
Line of Credit [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Line of Credit Facility, Commitment Fee Percentage		0.20%
Weighted average interest rate during the year		1.00%
Line of Credit [Member] \| credit facility 2015 [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Borrowings			$ 445,000,000
Repayments			(340,000,000)
Balance at December 31, 2015			105,000,000
Total revolving credit facilities at December 31						$ 600,000,000
Lines of credit			$ 105,000,000			$ 105,000,000
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate	1.00%
Line of Credit [Member] \| Federal Funds Effective Swap Rate [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate	0.50%
Minimum [Member] \| Line of Credit [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Line of Credit Facility, Commitment Fee Percentage	0.125%
Minimum [Member] \| Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate	0.875%
Minimum [Member] \| Line of Credit [Member] \| Base Rate [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate	0.00%
Maximum [Member] \| Line of Credit [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Line of Credit Facility, Commitment Fee Percentage	0.30%
Maximum [Member] \| Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate	1.55%
Maximum [Member] \| Line of Credit [Member] \| Base Rate [Member]
Line of Credit Facility, Amount Outstanding [Roll Forward]
Spread on variable rate	0.55%