Annual report pursuant to Section 13 and 15(d)

Unsecured Lines Of Credit Payable - Repayments and Borrowings on Unsecured Lines of Credit (Details)

v2.4.1.9
Unsecured Lines Of Credit Payable - Repayments and Borrowings on Unsecured Lines of Credit (Details) (USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Line of Credit Facility [Line Items]      
Line of Credit Facility, Periodic Payment, Interest $ 196,000us-gaap_LineOfCreditFacilityPeriodicPaymentInterest $ 867,000us-gaap_LineOfCreditFacilityPeriodicPaymentInterest $ 1,253,000us-gaap_LineOfCreditFacilityPeriodicPaymentInterest
Line of Credit Facility, Amount Outstanding [Roll Forward]      
Balance at December 31, 2013 0us-gaap_LineOfCredit 0us-gaap_LineOfCredit  
Balance at December 31, 2014 50,000,000us-gaap_LineOfCredit 0us-gaap_LineOfCredit 0us-gaap_LineOfCredit
Line Of Credit Extension Term 1 year    
Line of Credit Facility, Commitment Fee Percentage 0.25%us-gaap_LineOfCreditFacilityCommitmentFeePercentage    
Line of Credit Facility, Commitment Fee Amount 1,267,000us-gaap_LineOfCreditFacilityCommitmentFeeAmount 1,267,000us-gaap_LineOfCreditFacilityCommitmentFeeAmount 1,062,000us-gaap_LineOfCreditFacilityCommitmentFeeAmount
Total revolving credit facilities at December 31 500,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity 500,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity 500,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Lines of credit 50,000,000us-gaap_LineOfCredit 0us-gaap_LineOfCredit 0us-gaap_LineOfCredit
Weighted average daily borrowings during the year 12,849,000us-gaap_LineOfCreditFacilityAverageOutstandingAmount 61,548,000us-gaap_LineOfCreditFacilityAverageOutstandingAmount 108,589,000us-gaap_LineOfCreditFacilityAverageOutstandingAmount
Maximum daily borrowings during the year 55,000,000us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod 135,000,000us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod 242,000,000us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod
Weighted average interest rate during the year 0.00%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod 0.00%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod 0.00%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod
Weighted average interest rate at period end 0.00%us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd    
Credit Facility No. 1 [Member]      
Line of Credit Facility, Amount Outstanding [Roll Forward]      
Balance at December 31, 2013 0us-gaap_LineOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo1Member 		   
Borrowings 10,000,000us-gaap_ProceedsFromLinesOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo1Member 		   
Repayments (5,000,000)us-gaap_RepaymentsOfLinesOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo1Member 		   
Balance at December 31, 2014 5,000,000us-gaap_LineOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo1Member 		   
Line of Credit Facility, Expiration Date Jun. 30, 2015    
Total revolving credit facilities at December 31 100,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo1Member 		   
Lines of credit 5,000,000us-gaap_LineOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo1Member 		   
Credit Facility No. 2 [Member]      
Line of Credit Facility, Amount Outstanding [Roll Forward]      
Balance at December 31, 2013 0us-gaap_LineOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo2Member 		   
Borrowings 45,000,000us-gaap_ProceedsFromLinesOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo2Member 		   
Repayments 0us-gaap_RepaymentsOfLinesOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo2Member 		   
Balance at December 31, 2014 45,000,000us-gaap_LineOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo2Member 		   
Line of Credit Facility, Expiration Date Jul. 31, 2016    
Total revolving credit facilities at December 31 400,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo2Member 		   
Lines of credit $ 45,000,000us-gaap_LineOfCredit
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo2Member 		   
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%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo1Member
/ us-gaap_VariableRateAxis
= us-gaap_LondonInterbankOfferedRateLIBORMember 		   
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%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_LineOfCreditFacilityAxis
= wre_CreditFacilityNo2Member
/ us-gaap_VariableRateAxis
= us-gaap_LondonInterbankOfferedRateLIBORMember